Publications by authors named "Amit Chaudhary"

59 Publications

Identification of vaccine targets in pathogens and design of a vaccine using computational approaches.

Sci Rep 2021 Sep 2;11(1):17626. Epub 2021 Sep 2.

Texas Children's Hospital Center for Vaccine Development, Departments of Pediatrics and Molecular Virology and Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA.

Antigen identification is an important step in the vaccine development process. Computational approaches including deep learning systems can play an important role in the identification of vaccine targets using genomic and proteomic information. Here, we present a new computational system to discover and analyse novel vaccine targets leading to the design of a multi-epitope subunit vaccine candidate. The system incorporates reverse vaccinology and immuno-informatics tools to screen genomic and proteomic datasets of several pathogens such as Trypanosoma cruzi, Plasmodium falciparum, and Vibrio cholerae to identify potential vaccine candidates (PVC). Further, as a case study, we performed a detailed analysis of the genomic and proteomic dataset of T. cruzi (CL Brenner and Y strain) to shortlist eight proteins as possible vaccine antigen candidates using properties such as secretory/surface-exposed nature, low transmembrane helix (< 2), essentiality, virulence, antigenic, and non-homology with host/gut flora proteins. Subsequently, highly antigenic and immunogenic MHC class I, MHC class II and B cell epitopes were extracted from top-ranking vaccine targets. The designed vaccine construct containing 24 epitopes, 3 adjuvants, and 4 linkers was analysed for its physicochemical properties using different tools, including docking analysis. Immunological simulation studies suggested significant levels of T-helper, T-cytotoxic cells, and IgG1 will be elicited upon administration of such a putative multi-epitope vaccine construct. The vaccine construct is predicted to be soluble, stable, non-allergenic, non-toxic, and to offer cross-protection against related Trypanosoma species and strains. Further, studies are required to validate safety and immunogenicity of the vaccine.
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http://dx.doi.org/10.1038/s41598-021-96863-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8413327PMC
September 2021

Network pharmacological evaluation of bioactive phytochemicals for identifying novel potential inhibitors against neurodegenerative disorder.

J Biomol Struct Dyn 2021 Jul 19:1-12. Epub 2021 Jul 19.

Amity Institute of Biotechnology, Amity University, Noida, India.

Neurodegenerative disorders are illnesses that are responsible for neuronal cell death and resulting in lifelong cognitive problems. Due to their unclear mechanism, there are no effective drugs available for the treatment. For a long time, herbal drugs have been used as a role model in the field of the drug discovery process. (Ashwagandha) in the Indian medicinal system (Ayurveda) is used for several neuronal disorders like insomnia and memory loss for decades. This study aims to identify active components of (WS) as potential inhibitors for the treatment of neurodegenerative diseases (ND). To fulfill this objective, Network pharmacology approach, gene ontology, pharmacokinetics analysis, molecular docking, and molecular dynamics simulation (MDS) studies were performed. A total of 77 active components in WS, 175 predicted neurodegenerative targets of WS, and 8085 ND-related targets were identified from different databases. The network analysis showed that the top ten targets APP, EGFR, MAPK1, ESR1, HSPA4, PRKCD, MAPK3, ABL1, JUN, and GSK3B were found as significant target related to ND. On the basis of gene ontology and topology analysis results, APP was found as a significant target related to Alzheimer's disease pathways. Molecular docking results found that Anahygrine, Cuscohygrine, Isopelletierine, and Nicotine showed the best binding affinities -5.55, -4.73, -4.04, and -4.11 Kcal/mol. Further, MDS results suggested that Isopelletierine and Nicotine could be used as potential inhibitors against APP protein and could be useful for the treatment of Alzheimer's disease.Communicated by Ramaswamy H. Sarma.
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http://dx.doi.org/10.1080/07391102.2021.1951355DOI Listing
July 2021

A review on post-traumatic stress disorder (PTSD): "Symptoms, Therapies and Recent Case Studies".

Curr Mol Pharmacol 2021 May 25. Epub 2021 May 25.

Department of School of Pharmacy, Abhilashi University, Chail Chowk, tehsil Chachyot, Mandi, Himachal Pradesh 175028, India.

Post-traumatic stress disorder (PTSD), previously known as battle fatigue syndrome or shell shock, is a severe mental disturbance condition that is normally triggered by the experience of some frightening/scary events or trauma where a person undergoes some serious physical or mental harm or threatened. PTSD is a long-life effect of the continuous occurrence of traumatic conditions which, leading the production of feelings of helplessness, intense fear, and horror in the person. There are various examples of events that can cause PTSD, such as physical, mental, or sexual assault at home or working place by others, unexpected death of a loved one, an accidental event, war, or some kind of natural disaster. Treatment of PTSD includes the removal or reduction of these emotional feelings or symptoms with the aim to improve the daily life functioning of a person. Problems which are needed to be considered in case of PTSD like ongoing trauma, abusive or bad relationships. Various drugs which are used for the treatment of PTSD include selective serotonin reuptake inhibitors (SSRIs) (citalopram, fluvoxamine, fluoxetine, etc.); tricyclic antidepressants (amitriptyline and isocarboxazid); mood stabilizers (Divalproex and lamotrigine); atypical antipsychotics (aripiprazole and quetiapine), etc. In this review, we have covered the different risk factors, case studies related to various treatment options with different age group peoples in PTSD and their effects on them. We have also covered the symptoms and associated disorders which can play a key role in the development of PTSD.
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http://dx.doi.org/10.2174/1874467214666210525160944DOI Listing
May 2021

Casuarictin: A new herbal drug molecule for Alzheimer's disease as inhibitor of presenilin stabilization factor like protein.

Heliyon 2020 Nov 21;6(11):e05546. Epub 2020 Nov 21.

Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj 211004, India.

Alzheimer's disease is a progressive neurodegenerative disorder. In this disease neurodegeneration occurs due to deposition of aggregated amyloid-beta plaques and neurofibrillary tangles (hyperphosphorylated tau proteins). Present study focuses on interaction of different phytochemicals with presenilin stabilization factor like protein (PSFL). PSFL protein is known to stabilize Presenilin, which is mainly involved in intramembrane hydrolysis of selected type- I membrane proteins, including amyloid-beta precursor protein, and produces amyloid-beta protein. Amyloid-beta are small peptides comprising of 36-43 amino acids, which play a significant role in senile plaques formation in the brains of Alzheimer patients. Virtual screening and docking of phytochemicals with PSFL protein was done to find the potential inhibitor. Based on binding affinity, docked energy and molecular dynamics simulations, three phytochemicals namely Saponin, Casuarictin, and Enoxolone, were identified as potential inhibitors for the target protein.
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http://dx.doi.org/10.1016/j.heliyon.2020.e05546DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7689514PMC
November 2020

Screening natural inhibitors against upregulated G-protein coupled receptors as potential therapeutics of Alzheimer's disease.

J Biomol Struct Dyn 2020 Sep 9:1-12. Epub 2020 Sep 9.

Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad Prayagraj (Allahabad), Uttar Pradesh, India.

Computational approaches have been helpful in high throughput screening of drug libraries and designing ligands against receptors. Alzheimer's disease is a complex neurological disorder, which causes dementia. In this disease neurons are damaged due to formation of Amyloid-beta plaques and neurofibrillary tangles, which along with some other factors contributes to disease development and progression. The objective of this study was to predict tertiary structures of five G-protein coulped neurotransmitter receptors; CHRM5, CYSLTR2, DRD5, GALR1 and HTR2C, that are upregulated in Alzheimer's disease, and to screen potential inhibitors for against these receptors. In this study, Comparative modelling, molecular docking, MMGBSA analysis, ADMET screening and molecular dynamics simulation were performed. Tertiary structures of the five GPCRs were predicted and further subjected to molecular docking against natural compounds. Pharmacokinetic studies of natural compounds were also conducted for assessing drug-likeness properties. Molecular dynamics simulations were performed to investigate the structural stability and binding affinities of each complex. Finally, the results suggested that ZINC04098704, ZINC31170017, ZINC05998597, ZINC67911229, and ZINC67910690 had better binding affinity with CHRM5, CYSLTR2, DRD5, GALR1, and HTR2C (5-HT2C) proteins, respectively.Communicated by Ramaswamy H. Sarma.
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http://dx.doi.org/10.1080/07391102.2020.1817784DOI Listing
September 2020

Proniosomes: the effective and efficient drug-carrier system.

Ther Deliv 2020 02 15;11(2):125-137. Epub 2020 Jan 15.

Kharvel Subharti College of Pharmacy, Swami Vivekanand Subharti University, NH-58, Meerut 250005, Uttar Pradesh, India.

Niosomes, liposomes and proniosomes are the most abundantly used vesicular systems for the transdermal delivery of drugs. Proniosomes are nonhydrated niosomes, which, upon hydration, form niosomes. Various researches have proved the advantages of proniosomes over the other conventional dosage forms currently available in the market. Proniosomes overcome physical stability problems involved with other vesicular systems such as leaking, fusion and aggregation. The stability and shelf life of proniosomes especially have been found to be much better and prolonged in comparison to other vesicular systems such as liposomes. The present review has been written in an effort to bring yet another viewpoint from a different angle and curated to compile the latest updates in this highly attractive delivery system from today's research point.
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http://dx.doi.org/10.4155/tde-2019-0065DOI Listing
February 2020

Interaction network analysis of YBX1 for identification of therapeutic targets in adenocarcinomas.

J Biosci 2019 Jun;44(2)

Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad 211 004, India.

Human Y-box binding protein-1 (YBX1) is a member of highly conserved cold-shock domain protein family, which is involved in transcriptional as well as translational regulation of many genes. Nuclear localization of YBX1 has been observed in various cancer types and it's overexpression has been linked to adverse clinical outcome and poor therapy response, but no diagnostic or therapeutic correlation has been established so far. This study aimed to identify differentially expressed novel genes among the interactors of YBX1 in different cancer types. Analysis of RNA-Seq data for colorectal, lung, prostate and stomach adenocarcinoma identified 39 unique genes, which are differentially expressed in the four adenocarcinoma types. Gene-enrichment analysis for the differentially expressed genes from individual adenocarcinoma with focus on unique genes resulted in a total of 57 gene sets specific to each adenocarcinoma. Gene ontology for commonly expressed genes suggested the pathways and possible mechanisms through which they affect each adenocarcinoma type considered in the study. Gene regulatory network constructed for the common genes and network topology was analyzed for the central nodes. Here 12 genes were found to play important roles in the network formation; among them, two genes FOXM1 and TOP2A were found to be in central network formation, which makes them a common target for therapeutics. Furthermore, five common differentially expressed genes in all adenocarcinomas were also identified.
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June 2019

Surgical options in the management of landmine blast injuries of lower limb: a randomised prospective study.

Acta Orthop Belg 2019 Mar;85(1):21-34

Landmine blast injuries are high velocity shattering injuries that produce ghastly and gory wounds, presenting a dilemma to the treating surgeon, especially when the literature on this subject is limited. The aim of the present study is to enlist various surgical procedures that can be explored to treat such complex injuries. 60 cases having varied degrees of involvement of the lower limb from mine blasts were managed. Surgical treatment was tailored to the individual requirement depending on the extent and severity of injury. Serial surgical wound debridement was an integral part of all these procedures. Limb length preservation was possible in 70% cases. A combination of surgical approaches and procedures from fixation to different types of amputations can be employed for treating mine blast injuries to maximise residual limb function.
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March 2019

Impact of miRNA-mRNA Profiling and Their Correlation on Medulloblastoma Tumorigenesis.

Mol Ther Nucleic Acids 2018 Sep 19;12:490-503. Epub 2018 Jun 19.

Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USA. Electronic address:

Medulloblastoma (MB) is a clinically challenging, childhood brain tumor with a diverse genetic makeup and differential miRNA profile. Aiming to identify deregulated miRNAs in MB, the miRNA expression profile of human MB samples was compared to that of normal cerebellar tissues. As a result, 8 upregulated and 64 downregulated miRNAs were identified in MB samples. Although various algorithms have been developed to predict the interaction between miRNA-mRNA pairs, the complexity and fidelity of miRNA-mRNA remain a concern. Therefore, to identify the signatures of miRNA-mRNA interactions essential for MB pathogenesis, miRNA profiling, RNA sequencing, and ingenuity pathway analysis (IPA) were performed in the same primary human MB samples. Further, when miR-217 was inhibited, a significant upregulation of predicted target genes SIRT1, ROBO1, FOXO3, and SMAD7 in HDMB03 cells was observed, confirming the validity of our approach. Functional analysis revealed that the inhibition of miR-217 in HDMB03 cells suppresses colony formation, migration, invasion, promoted apoptosis, and arrested cell population in S phase, indicating that manipulation of miR-217 may have a therapeutic potential for MB patients. Therefore, our study provides an essential platform for future investigations of specific miRNAs responsible for MB pathogenesis.
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http://dx.doi.org/10.1016/j.omtn.2018.06.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6070673PMC
September 2018

Implication of orphan histidine kinase (OhkAsp) in biosynthesis of doxorubicin and daunorubicin in Streptomyces peucetius ATCC 27952.

Microbiol Res 2018 Sep 22;214:37-46. Epub 2018 May 22.

Institute of Biomolecule Reconstruction (iBR), Department of Life Science and Biochemical Engineering, Sun Moon University, 70 Sun Moon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea; Department of BT-Convergent Pharmaceutical Engineering, Sun Moon University, 70 Sun Moon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea. Electronic address:

The orphan histidine kinase (HK) from Streptomyces peucetius ATCC 27952 (ohkAsp) was found to be implicated in the regulation of doxorubicin (DOX)/daunorubicin (DNR) biosynthesis, self-defense and developmental attributes. OhkAsp is a homolog of OhkA from Streptomyces coelicolor and Streptomyces avermitilis (with 73 and 75% identity). As in its homologs, S. peucetius mutant with deletion of ohkAsp was found to enhance metabolite biosynthesis and impaired the morphological differentiation. But, unlike its homologs from Streptomyces coelicolor and Streptomyces avermitilis, differential enhancement in level of secondary metabolite production was found in overexpression mutants apart from deletion mutant. The deflection in characteristics of OhkA in its homologue from S. peucetius ATCC 27952, and its imminent implications was monitered by making various mutants with differential expression level of ohkAsp. The variations were observed in the morphology of mutants, transcriptional level of effectors and regulators of DOX/DNR biosynthesis pathway, DOX/DNR precursor pool and biomass accumulation. Based on comparisons of domain arrangements among its homologs, Low Complexity Region (LCR) present on the OhkAsp was the only domain that stood out. Further, the LCR on OhkAsp was found to be overlapping with a putative receiver domain responsible for interaction with response regulator. The imminent implications of differential expression level of ohkAsp on: regulation and biosynthesis of DOX/DNR, morphological differentiation, DOX/DNR precursor pool and biomass accumulation were explored in this study.
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http://dx.doi.org/10.1016/j.micres.2018.05.007DOI Listing
September 2018

Expression and network analysis of YBX1 interactors for identification of new drug targets in lung adenocarcinoma.

J Genomics 2018 26;6:103-112. Epub 2018 Jun 26.

Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad, India-211004.

Y-Box Binding protein 1 (YBX-1) is known to be involved in various types of cancers. It's interactors also play major role in various cellular functions. Present work aimed to study the expression profile of the YBX-1 interactors during lung adenocarcinoma (LUAD). The differential expression analysis involved 57 genes from 95 lung adenocarcinoma samples, construction of gene network and topology analysis. A Total of 43 genes were found to be differentially expressed from which 17 genes were found to be down regulated and 26 genes were up-regulated. We observed that Polyadenylate-binding protein 1 (PABPC1), a protein involved in YBX1 translation, is highly correlated with YBX1. The interaction network analysis for a differentially expressed non-coding RNA Growth Arrest Specific 5 (GAS5) suggests that two proteins namely, Growth Arrest Specific 2 (GAS2) and Peripheral myelin protein 22 (PMP22) are potentially involved in LUAD progression. The network analysis and differential expression suggests that Collagen type 1 alpha 2 (COL1A2) can be potential biomarker and target for LUAD.
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http://dx.doi.org/10.7150/jgen.20581DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6030768PMC
June 2018

Tumor stroma-targeted antibody-drug conjugate triggers localized anticancer drug release.

J Clin Invest 2018 07 4;128(7):2927-2943. Epub 2018 Jun 4.

Tumor Angiogenesis Unit, Mouse Cancer Genetics Program (MCGP), National Cancer Institute (NCI), NIH, Frederick, Maryland, USA.

Although nonmalignant stromal cells facilitate tumor growth and can occupy up to 90% of a solid tumor mass, better strategies to exploit these cells for improved cancer therapy are needed. Here, we describe a potent MMAE-linked antibody-drug conjugate (ADC) targeting tumor endothelial marker 8 (TEM8, also known as ANTXR1), a highly conserved transmembrane receptor broadly overexpressed on cancer-associated fibroblasts, endothelium, and pericytes. Anti-TEM8 ADC elicited potent anticancer activity through an unexpected killing mechanism we term DAaRTS (drug activation and release through stroma), whereby the tumor microenvironment localizes active drug at the tumor site. Following capture of ADC prodrug from the circulation, tumor-associated stromal cells release active MMAE free drug, killing nearby proliferating tumor cells in a target-independent manner. In preclinical studies, ADC treatment was well tolerated and induced regression and often eradication of multiple solid tumor types, blocked metastatic growth, and prolonged overall survival. By exploiting TEM8+ tumor stroma for targeted drug activation, these studies reveal a drug delivery strategy with potential to augment therapies against multiple cancer types.
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http://dx.doi.org/10.1172/JCI120481DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6025988PMC
July 2018

Improved production of 1-deoxynojirymicin in Escherichia coli through metabolic engineering.

World J Microbiol Biotechnol 2018 May 23;34(6):77. Epub 2018 May 23.

Department of Life Science and Biochemical Engineering, Institute of Biomolecule Reconstruction (iBR), Sun Moon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam, 31460, Republic of Korea.

Azasugars, such as 1-deoxynojirymicin (1-DNJ), are associated with diverse pharmaceutical applications, such as antidiabetic, anti-obesity, anti-HIV, and antitumor properties. Different azasugars have been isolated from diverse microbial and plant sources though complicated purification steps, or generated by costly chemical synthesis processes. But the biosynthesis of such potent molecules using Escherichia coli as a heterologous host provides a broader opportunity to access these molecules, particularly by utilizing synthetic biological, metabolic engineering, and process optimization approaches. This work used an integrated approach of synthetic biology, enzyme engineering, and pathway optimization for rational metabolic engineering, leading to the improved production of 1-DNJ. The production of 1-DNJ in recombinant E. coli culture broth was confirmed by enzymatic assays and mass spectrometric analysis. Specifically, the pathway engineering for its key precursor, fructose-6-phosphate, along with optimized media condition, results in the highest production levels. When combined, 1-DNJ production was extended to ~ 273 mg/L, which is the highest titer of production of 1-DNJ reported using E. coli.
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http://dx.doi.org/10.1007/s11274-018-2462-3DOI Listing
May 2018

Engineering co-culture system for production of apigetrin in Escherichia coli.

J Ind Microbiol Biotechnol 2018 Mar 24;45(3):175-185. Epub 2018 Jan 24.

Lab of Marine Medicinal Materials, Institute of Marine Biochemistry (IMBC), Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Hanoi, Vietnam.

Microbial cells have extensively been utilized to produce value-added bioactive compounds. Based on advancement in protein engineering, DNA recombinant technology, genome engineering, and metabolic remodeling, the microbes can be re-engineered to produce industrially and medicinally important platform chemicals. The emergence of co-culture system which reduces the metabolic burden and allows parallel optimization of the engineered pathway in a modular fashion restricting the formation of undesired byproducts has become an alternative way to synthesize and produce bioactive compounds. In this study, we present genetically engineered E. coli-based co-culture system to the de novo synthesis of apigetrin (APG), an apigenin-7-O-β-D-glucopyranoside of apigenin. The culture system consists of an upstream module including 4-coumarate: CoA ligase (4CL), chalcone synthase, chalcone flavanone isomerase (CHS, CHI), and flavone synthase I (FNSI) to synthesize apigenin (API) from p-coumaric acid (PCA). Whereas, the downstream system contains a metabolizing module to enhance the production of UDP-glucose and expression of glycosyltransferase (PaGT3) to convert API into APG. To accomplish this improvement in titer, the initial inoculum ratio of strains for making the co-culture system, temperature, and media component was optimized. Following large-scale production, a yield of 38.5 µM (16.6 mg/L) of APG was achieved. In overall, this study provided an efficient tool to synthesize bioactive compounds in microbial cells.
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http://dx.doi.org/10.1007/s10295-018-2012-xDOI Listing
March 2018

The fourth annual BRDS on genome editing and silencing for precision medicines.

Drug Deliv Transl Res 2018 02;8(1):266-272

Department of Pharmaceutical Sciences, University of Nebraska Medical Center (UNMC), 986025 Nebraska Medical Center, Omaha, NE, 68198-6025, USA.

Precision medicine is promising for treating human diseases, as it focuses on tailoring drugs to a patient's genes, environment, and lifestyle. The need for personalized medicines has opened the doors for turning nucleic acids into therapeutics. Although gene therapy has the potential to treat and cure genetic and acquired diseases, it needs to overcome certain obstacles before creating the overall prescription drugs. Recent advancement in the life science has helped to understand the effective manipulation and delivery of genome-engineering tools better. The use of sequence-specific nucleases allows genetic changes in human cells to be easily made with higher efficiency and precision than before. Nanotechnology has made rapid advancement in the field of drug delivery, but the delivery of nucleic acids presents unique challenges. Also, designing efficient and short time-consuming genome-editing tools with negligible off-target effects are in high demand for precision medicine. In the fourth annual Biopharmaceutical Research and Development Symposium (BRDS) held at the University of Nebraska Medical Center (UNMC) on September 7-8, 2017, we covered different facets of developing tools for precision medicine for therapeutic and diagnosis of genetic disorders.
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http://dx.doi.org/10.1007/s13346-017-0457-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5997254PMC
February 2018

Docking-based Screening of Phytochemicals as Inhibitors of Human Histamine H2 Receptor.

Pharmacogn Mag 2017 Oct 11;13(Suppl 3):S706-S714. Epub 2017 Oct 11.

Department of Biotechnology, MNNIT, Allahabad, Uttar Pradesh, India.

Background: L. is generally known as Peepal and belongs to family . The tree is a source of many compounds having high medicinal value. In gastrointestinal tract, histamine H2 receptors have key role in histamine-stimulated gastric acid secretion. Their over stimulation causes its excessive production which is responsible for gastric ulcer.

Objective: This study aims to screen the range of phytochemicals present in for binding with human histamine H2 and identify therapeutics for a gastric ulcer from the plant.

Materials And Methods: In this work, a 3D-structure of human histamine H2 receptor was modeled by using homology modeling and the predicted model was validated using PROCHECK. Docking studies were also performed to assess binding affinities between modeled receptor and 34 compounds. Molecular dynamics simulations were done to identify most stable receptor-ligand complexes. Absorption, distribution, metabolism, excretion, and screening was done to evaluate pharmacokinetic properties of compounds.

Results: The results suggest that seven ligands, namely, germacrene, bergaptol, lanosterol, Ergost-5-en-3beta-ol, α-amyrin acetate, bergapten, and γ-cadinene showed better binding affinities.

Conclusion: Among seven phytochemicals, lanosterol and α-amyrin acetate were found to have greater stability during simulation studies. These two compounds may be a suitable therapeutic agent against histamine H2 receptor.

Summary: This study was performed to screen antiulcer compounds from . Molecular modeling, molecular docking and MD simulation studies were performed with selected phytochemicals from . The analysis suggests that Lanosterol and α-amyrin may be a suitable therapeutic agent against histamine H2 receptor. This study facilitates initiation of the herbal drug discovery process for the antiulcer activity. ADMET: Absorption, distribution, metabolism, excretion and toxicity, DOPE: Discrete Optimized Potential Energy, OPLS: Optimized potential for liquid simulations, RMSD: Root-mean-square deviation, HOA: Human oral absorption, MW: Molecular weight, SP: Standard-precision, XP: Extra-precision, GPCRs: G protein-coupled receptors, SASA: Solvent accessible surface area, Rg: Radius of gyration, NHB: Number of hydrogen bond.
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http://dx.doi.org/10.4103/pm.pm_49_17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5669120PMC
October 2017

Role of Y Box Protein-1 in cancer: As potential biomarker and novel therapeutic target.

J Cancer 2017 3;8(10):1900-1907. Epub 2017 Jul 3.

Department of Biotechnology, MNNIT Allahabad-211004.

The Y-box binding protein (YB-1) is known to be a multifunctional transcription and translation factor during expression of several proteins. It is a vital oncoprotein that regulates cancer cell progression and proliferation. YB-1 is over-expressed in various human cancers such as breast cancer, colon cancer, lung cancer, gastric cancer oesophageal cancer and glioblastoma. Nuclear expression of YB-1 is found to be associated with multidrug resistance and cancer cell progression. YB-1 is reported to regulate many cellular signalling pathways in different types of cancer proliferation. Knowledge about nuclear localization and nuclear level expression of YB-1 in different cancers has been correlated with prospective prognosis of cancer. This review discusses the prospects of YB-1 as a potential biomarker as well as therapeutic target in lieu of their role during cancer progression and multidrug resistance.
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http://dx.doi.org/10.7150/jca.17689DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5556654PMC
July 2017

EGFR-Targeted Cationic Polymeric Mixed Micelles for Codelivery of Gemcitabine and miR-205 for Treating Advanced Pancreatic Cancer.

Mol Pharm 2017 09 31;14(9):3121-3133. Epub 2017 Jul 31.

Department of Pharmaceutical Sciences, University of Nebraska Medical Center , Omaha, Nebraska 68198, United States.

Gemcitabine (GEM), a first-line chemotherapy for pancreatic cancer undergoes rapid metabolism and develops chemoresistance after repeated administration. We previously demonstrated that the combination of GEM and miR-205 provides an effective therapeutic strategy to sensitize GEM-resistant pancreatic cancer cells. Since epidermal growth factor receptor (EGFR) is overexpressed in pancreatic cancer cells, in this study, we aimed to deliver mixed micelles containing GEM and miR-205 decorated with EGFR-targeting cetuximab (C225) monoclonal antibody for targeted therapy. Cetuximab C225 was conjugated to malemido-poly(ethylene glycol)-block-poly(2-methyl-2-carboxyl-propylene carbonate-graft-dodecanol (C225-PEG-PCD) to prepare mixed micelles with mPEG-b-PCC-g-GEM-g-DC-g-TEPA for targeted codelivery of GEM and miR-205. This mixed micelle formulation showed a significant enhancement in EGFR-mediated cellular uptake in GEM-resistant MIA PaCa-2 cells. Further, an enhanced tumor accumulation of C225-micelles conjugated with near-infrared fluorescent Cy7.5 dye and Dy677-labeled miR-205 in orthotopic pancreatic tumor bearing NSG mice was evident after systemic administration. In addition, inhibition of tumor growth was also observed with increased apoptosis and reduced EMT after treatment with C225-micelles containing GEM and miR-205. Therefore, we believe that the targeted delivery of GEM and miR-205 in combination could be a novel strategy for treating advanced pancreatic cancer.
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http://dx.doi.org/10.1021/acs.molpharmaceut.7b00355DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6710626PMC
September 2017

Chemosensitization and inhibition of pancreatic cancer stem cell proliferation by overexpression of microRNA-205.

Cancer Lett 2017 08 20;402:1-8. Epub 2017 May 20.

Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USA. Electronic address:

Treatment of pancreatic cancer with gemcitabine (GEM) is limited due to its rapid plasma metabolism and development of chemoresistance. MicroRNA (miRNA) regulates cancer stem cell (CSC) maintenance and induces chemoresistance in cancer cells. In this study, we observed differential downregulation of miR-205 (miR-205-5p) in human pancreatic cancer tissues and cells. Compared to GEM-sensitive MIA PaCa-2 cells, miR-205 was highly downregulated in GEM-resistant MIA PaCa-2R cells. Lentivirus-mediated overexpression of miR-205 inhibits MIA PaCa-2R cell proliferation after GEM-treatment. Further investigation confirmed that miR-205 alone significantly reduces the proliferation of CSCs and tumor growth in mouse models. However, miR-205 in combination with GEM was more efficient in reducing the proliferation of CSCs and 3D spheroids. Moreover, miR-205 overexpressing MIA PaCa-2R cells induced orthotopic tumor growth was significantly inhibited after intravenous administration of GEM-conjugated methoxy poly(ethylene glycol)-block-poly(2-methyl-2-carboxyl-propylene carbonate)-graft-gemcitabine-graft-dodecanol (mPEG-b-PCC-g-GEM-g-DC) (mPEG-b-PCC-g-GEM-g-DC) polymeric micelles. Also, a reduction in CSCs, EMT and chemoresistance markers was observed in miR-205 overexpressing MIA PaCa-2R cells. Immunohistochemical analysis of orthotopic tumors showed a decrease in drug resistance protein caveolin-1 and cell proliferation marker Ki-67 in combination treatment. Overall, our findings suggest that miR-205 resensitizes GEM-resistant pancreatic cancer cells to GEM and acts as a tumor suppressor miRNA.
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http://dx.doi.org/10.1016/j.canlet.2017.05.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5673079PMC
August 2017

Design, Synthesis and Biological Evaluation of novel Hedgehog Inhibitors for treating Pancreatic Cancer.

Sci Rep 2017 05 10;7(1):1665. Epub 2017 May 10.

Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE, 68198, USA.

Hedgehog (Hh) pathway is involved in epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) maintenance resulting in tumor progression. GDC-0449, an inhibitor of Hh pathway component smoothened (Smo) has shown promise in the treatment of various cancers including pancreatic cancer. However, the emergence of resistance during GDC-0449 treatment with numerous side effects limits its use. Therefore, here we report the design, synthesis and evaluation of novel GDC-0449 analogs using N-[3-(2-pyridinyl) phenyl] benzamide scaffold. Cell-based screening followed by molecular simulation revealed 2-chloro-N -[4-chloro-3-(2-pyridinyl)phenyl]-N ,N -bis(2-pyridinylmethyl)-1,4-benzenedicarboxamide (MDB5) as most potent analog, binding with an extra interactions in seven-transmembrane (7-TM) domain of Smo due to an additional 2-pyridylmethyl group than GDC-0449. Moreover, MDB5 was more efficient in inhibiting Hh pathway components as measured by Gli-1 and Shh at transcriptional and translational levels. Additionally, a significant reduction of ALDH1, CD44 and Oct-3/4, key markers of pancreatic CSC was observed when MIA PaCa-2 cells were treated with MDB5 compared to GDC-0449. In a pancreatic tumor mouse model, MDB5 containing nanoparticles treated group showed significant inhibition of tumor growth without loss in body weight. These evidence highlight the enhanced Hh pathway inhibition and anticancer properties of MDB5 leaving a platform for mono and/or combination therapy.
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http://dx.doi.org/10.1038/s41598-017-01942-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5431907PMC
May 2017

Eradication of Tumors through Simultaneous Ablation of CD276/B7-H3-Positive Tumor Cells and Tumor Vasculature.

Cancer Cell 2017 04;31(4):501-515.e8

Tumor Angiogenesis Unit, Mouse Cancer Genetics Program (MCGP), National Cancer Institute (NCI), NIH, Frederick, MD 21702, USA. Electronic address:

Targeting the tumor vasculature with antibody-drug conjugates (ADCs) is a promising anti-cancer strategy that in order to be realized must overcome several obstacles, including identification of suitable targets and optimal warheads. Here, we demonstrate that the cell-surface protein CD276/B7-H3 is broadly overexpressed by multiple tumor types on both cancer cells and tumor-infiltrating blood vessels, making it a potentially ideal dual-compartment therapeutic target. In preclinical studies CD276 ADCs armed with a conventional MMAE warhead destroyed CD276-positive cancer cells, but were ineffective against tumor vasculature. In contrast, pyrrolobenzodiazepine-conjugated CD276 ADCs killed both cancer cells and tumor vasculature, eradicating large established tumors and metastases, and improving long-term overall survival. CD276-targeted dual-compartment ablation could aid in the development of highly selective broad-acting anti-cancer therapies.
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http://dx.doi.org/10.1016/j.ccell.2017.03.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5458750PMC
April 2017

Post-traumatic Medial Meniscal Cyst in young: A case report.

J Orthop Case Rep 2016 Jul-Aug;6(3):7-9

Department of Orthopaedics, Dr. D.Y. Patil Medical College and Research Centre, Pune. Maharashtra, India.

Introduction: Meniscal cysts are rare, in that cysts of lateral meniscus are 3 times to 10 times more common than those of medial meniscus. Etiology of meniscal cysts includes trauma which results in contusion and haemorrage within the substance of meniscus leading to mucoid degeneration. Degeneration with age results in local necrosis and mucoid degeneration into a cyst, developmental inclusion of synovial cells within the substance of the meniscus and often are a result of extrusion of synovial fluid through a tear of the meniscus, resulting in a one-way valve effect of the tear. Arthroscopic partial menisectomy followed by cyst decompression is currently recommended for treatment of a meniscal cyst.

Case Presentation: We present a case of 18-year-old female with c/o pain and swelling in right knee had h/o trauma 3 yrs back. On examination, swelling 1x2 cm on medial tibial condyle, firm in consistency fixed to bone. MRI suggests grade 3 horizontal tear in posterior horn of medial meniscus and parameniscal cyst adjacent to medial meniscus. In this report, medial parameniscal cyst was resected using an arthroscopic posterior trans-septal approach. There have been no recurrences to date, and patient returned to her previous level of activity.

Conclusion: A posterior trans-septal approach is useful for resection of a meniscal cyst arising from the posterior horn of the medial meniscus.
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http://dx.doi.org/10.13107/jocr.2250-0685.474DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5245944PMC
January 2017

The third annual BRDS on research and development of nucleic acid-based nanomedicines.

Drug Deliv Transl Res 2017 02;7(1):188-193

Department of Pharmaceutical Sciences, 986025 Nebraska Medical Center, University of Nebraska Medical Center (UNMC), Omaha, NE, 68198-6025, USA.

The completion of human genome project, decrease in the sequencing cost, and correlation of genome sequencing data with specific diseases led to the exponential rise in the nucleic acid-based therapeutic approaches. In the third annual Biopharmaceutical Research and Development Symposium (BRDS) held at the Center for Drug Discovery and Lozier Center for Pharmacy Sciences and Education at the University of Nebraska Medical Center (UNMC), we highlighted the remarkable features of the nucleic acid-based nanomedicines, their significance, NIH funding opportunities on nanomedicines and gene therapy research, challenges and opportunities in the clinical translation of nucleic acids into therapeutics, and the role of intellectual property (IP) in drug discovery and development.
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http://dx.doi.org/10.1007/s13346-016-0345-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5673078PMC
February 2017

Overexpression of a pathway specific negative regulator enhances production of daunorubicin in bldA deficient Streptomyces peucetius ATCC 27952.

Microbiol Res 2016 Nov 22;192:96-102. Epub 2016 Jun 22.

Department of Life Science and Biochemical Engineering, SunMoon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea; Department of BT-Convergent Pharmaceutical Engineering, SunMoon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea. Electronic address:

The dnrO gene is the first regulator to be activated in the daunorubicin (DNR) biosynthesis pathway of Streptomyces peucetius ATCC 27952. DnrO is known for its self-repression capability while it activates rest of the DNR biosynthesis pathway through cascades of regulatory events. S. peucetius was found to contain no functional copy of bldA-tRNA while a detailed examination of dnrO codons reveals the presence of TTA codon, which is rarely encoded by bldA-tRNA. Therefore, for evaluating the role of dnrO in DNR production, multiple engineered strains of S. peucetius were generated by heterologously expressing bldA, dnrO and combination of bldA and dnrO. Using these strains, the effects of heterologously expressed bldA and overexpressed dnrO were evaluated on pathway specific regulators, mycelial densities and production of DNR. The results showed that the transcription level of dnrO and master regulator dnrI, was found to be elevated in bldA containing strain in comparison to dnrO overexpressed strain. The bldA containing strain produces 45.7% higher DNR than bldA deficient wild type strain from culture broth with OD600 of 1.45 at 72h. Heterologous expression of bldA-tRNA is accounted for increased transcription levels of the DNR pathway specific regulators and enhanced DNR production.
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http://dx.doi.org/10.1016/j.micres.2016.06.009DOI Listing
November 2016

Enhanced production of nargenicin A1 and creation of a novel derivative using a synthetic biology platform.

Appl Microbiol Biotechnol 2016 Dec 14;100(23):9917-9931. Epub 2016 Jul 14.

Department of Life Science and Biochemical Engineering, Sun Moon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam, 31460, Republic of Korea.

Nargenicin A1, an antibacterial produced by Nocardia sp. CS682 (KCTC 11297BP), demonstrates effective activity against various Gram-positive bacteria. Hence, we attempted to enhance nargenicin A1 production by utilizing the cumulative effect of synthetic biology, metabolic engineering and statistical media optimization strategies. To facilitate the modular assembly of multiple genes for genetic engineering in Nocardia sp. CS682, we constructed a set of multi-monocistronic vectors, pNV18L1 and pNV18L2 containing hybrid promoter (derived from ermE* and promoter region of neo ), ribosome binding sites (RBS), and restriction sites for cloning, so that each cloned gene was under its own promoter and RBS. The multi-monocistronic vector, pNV18L2 containing transcriptional terminator showed better efficiency in reporter gene assay. Thus, multiple genes involved in the biogenesis of pyrrole moiety (ngnN2, ngnN3, ngnN4, and ngnN5 from Nocardia sp. CS682), glucose utilization (glf and glk from Zymomonas mobilis), and malonyl-CoA synthesis (accA2 and accBE from Streptomyces coelicolor A3 (2)), were cloned in pNV18L2. Further statistical optimization of specific precursors (proline and glucose) and their feeding time led to ~84.9 mg/L nargenicin from Nocardia sp. GAP, which is ~24-fold higher than Nocardia sp. CS682 (without feeding). Furthermore, pikC from Streptomyces venezuelae was expressed to generate Nocardia sp. PikC. Nargenicin A1 acid was characterized as novel derivative of nargenicin A1 produced from Nocardia sp. PikC by mass spectrometry (MS) and nuclear magnetic resonance (NMR) analyses. We also performed comparative analysis of the anticancer and antibacterial activities of nargenicin A1 and nargenicin A1 acid, which showed a reduction in antibacterial potential for nargenicin A1 acid. Thus, the development of an efficient synthetic biological platform provided new avenues for enhancing or structurally diversifying nargenicin A1 by means of pathway designing and engineering.
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http://dx.doi.org/10.1007/s00253-016-7705-3DOI Listing
December 2016

Modulation of hepatocarcinogenesis in N-methyl-N-nitrosourea treated Balb/c mice by mushroom extracts.

Food Funct 2016 Jan;7(1):594-609

ANDI Centre of Excellence for Biomedical and Biomaterials Research, CBBR, Building, MSIRI, University of Mauritius, Réduit, Republic of Mauritius.

The hepatoprotective potential of edible mushrooms from Mauritius, namely Pleurotus sajor-caju and Agaricus bisporus was evaluated using an N-methyl-N-nitrosourea (MNU)-induced hepatocarcinogenesis Balb/c mice model. Mushroom extracts restored normal weight in MNU treated mice over a 3 month supplementation period. Blood parameter analyses indicated a clear modulation of hemoglobin concentration, leukocyte, platelet, lymphocyte, neutrophil, monocyte and eosinophil counts in MNU-induced mice (p < 0.05). Mushroom extract supplementation effectively reduced oxidative damage in MNU-primed mice, which was marked by a significant decrease in the extent of lipid peroxidation (p < 0.05) and a concomitant increase in the enzymatic antioxidant levels, primarily catalase, superoxide dismutase, glutathione reductase and peroxidase, and FRAP values (p < 0.05). DNA protective effects of the extracts were confirmed by Raman spectroscopy, where, the MNU-DNA interaction, as evidenced by an intense peak at 1254 cm(-1), was normalized. The findings demonstrate hepatoprotective, immunomodulatory and anti-carcinogenic effects and suggest the use of mushrooms as potential dietary prophylactics in cancer chemoprevention.
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http://dx.doi.org/10.1039/c5fo00870kDOI Listing
January 2016

Small molecules targeting microRNA for cancer therapy: Promises and obstacles.

J Control Release 2015 Dec 6;219:237-247. Epub 2015 Aug 6.

Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025 Nebraska Medical Center, Omaha, NE 68198-6025, USA. Electronic address:

Aberrant expression of miRNAs is critically implicated in cancer initiation and progression. Therapeutic approaches focused on regulating miRNAs are therefore a promising approach for treating cancer. Antisense oligonucleotides, miRNA sponges, and CRISPR/Cas9 genome editing systems are being investigated as tools for regulating miRNAs. Despite the accruing insights in the use of these tools, delivery concerns have mitigated clinical application of such systems. In contrast, little attention has been given to the potential of small molecules to modulate miRNA expression for cancer therapy. In these years, many researches proved that small molecules targeting cancer-related miRNAs might have greater potential for cancer treatment. Small molecules targeting cancer related miRNAs showed significantly promising results in different cancer models. However, there are still several obstacles hindering the progress and clinical application in this area. This review discusses the development, mechanisms and application of small molecules for modulating oncogenic miRNAs (oncomiRs). Attention has also been given to screening technologies and perspectives aimed to facilitate clinical translation for small molecule-based miRNA therapeutics.
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http://dx.doi.org/10.1016/j.jconrel.2015.08.011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4749151PMC
December 2015

Synthetic sugar cassettes for the efficient production of flavonol glycosides in Escherichia coli.

Microb Cell Fact 2015 Jun 9;14:76. Epub 2015 Jun 9.

Department of BT-Convergent Pharmaceutical Engineering, Institute of Biomolecule Reconstruction, Sun Moon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-Si, Chungnam, 336-708, Republic of Korea.

Background: A multi-monocistronic synthetic vector was used to assemble multiple genes of a nucleotide diphosphate (NDP)-sugar biosynthetic pathway to construct robust genetic circuits for the production of valuable flavonoid glycosides in Escherichia coli. Characterized functional genes involved in the biosynthesis of uridine diphosphate (UDP)-glucose and thymidine diphosphate (TDP)-rhamnose from various microbial sources along with glucose facilitator diffusion protein (glf) and glucokinase (glk) from Zymomonas mobilis were assembled and overexpressed in a single synthetic multi-monocistronic operon.

Results: The newly generated NDP-sugars biosynthesis circuits along with regiospecific glycosyltransferases from plants were introduced in E. coli BL21 (DE3) to probe the bioconversion of fisetin, a medicinally important polyphenol produced by various plants. As a result, approximately 1.178 g of fisetin 3-O-glucoside and 1.026 g of fisetin 3-O-rhamnoside were produced in UDP-glucose and TDP-rhamnose biosynthesis systems respectively, after 48 h of incubation in 3 L fermentor while supplementing 0.9 g of fisetin. These yields of fisetin glycosides represent ~99% of bioconversion of exogenously supplemented fisetin. The systems were also found to be highly effective in bio-transforming other flavonols (quercetin, kaempferol, myricetin) into their respective glycosides, achieving over 95% substrate conversion.

Conclusion: The construction of a synthetic expression vector for bacterial cell factory followed by subsequent re-direction of metabolic flux towards desirable products have always been revolutionized the biotechnological processes and technologies. This multi-monocistronic synthetic vector in a microbial platform is customizable to defined task and would certainly be useful for applications in producing and modifying such therapeutically valued plant secondary metabolites.
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http://dx.doi.org/10.1186/s12934-015-0261-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4459062PMC
June 2015

Rapid and high-throughput construction of microbial cell-factories with regulatory noncoding RNAs.

Biotechnol Adv 2015 Nov 29;33(6 Pt 1):914-30. Epub 2015 May 29.

Department of Chemical Engineering, Kyung Hee University, Gyeonggi-do 446-701, Republic of Korea. Electronic address:

Due to global crises such as pollution and depletion of fossil fuels, sustainable technologies based on microbial cell-factories have been garnering great interest as an alternative to chemical factories. The development of microbial cell-factories is imperative in cutting down the overall manufacturing cost. Thus, diverse metabolic engineering strategies and engineering tools have been established to obtain a preferred genotype and phenotype displaying superior productivity. However, these tools are limited to only a handful of genes with permanent modification of a genome and significant labor costs, and this is one of the bottlenecks associated with biofactory construction. Therefore, a groundbreaking rapid and high-throughput engineering tool is needed for efficient construction of microbial cell-factories. During the last decade, copious small noncoding RNAs (ncRNAs) have been discovered in bacteria. These are involved in substantial regulatory roles like transcriptional and post-transcriptional gene regulation by modulating mRNA elongation, stability, or translational efficiency. Because of their vulnerability, ncRNAs can be used as another layer of conditional control over gene expression without modifying chromosomal sequences, and hence would be a promising high-throughput tool for metabolic engineering. Here, we review successful design principles and applications of ncRNAs for high-throughput metabolic engineering or physiological studies of diverse industrially important microorganisms.
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http://dx.doi.org/10.1016/j.biotechadv.2015.05.009DOI Listing
November 2015

Metabolic engineering of rational screened Saccharopolyspora spinosa for the enhancement of spinosyns A and D production.

Mol Cells 2014 Oct 26;37(10):727-33. Epub 2014 Sep 26.

Institute of Biomolecule Reconstruction (iBR), Department of Pharmaceutical Engineering, Sun Moon University, Asan 333-708, Korea.

Spinosyns A and D are potent ingredient for insect control with exceptional safety to non-target organisms. It consists of a 21-carbon tetracyclic lactone with forosamine and tri-O-methylated rhamnose which are derived from S-adenosylmethionine. Although previous studies have revealed the involvement of metK1 (S-adenosylmethionine synthetase), rmbA (glucose-1-phosphate thymidylyltransferase), and rmbB (TDP-D-glucose-4, 6-dehydratase) in the biosynthesis of spinosad, expression of these genes into rational screened Saccharopolyspora spinosa (S. spinosa MUV) has not been elucidated till date. In the present study, S. spinosa MUV was developed to utilize for metabolic engineering. The yield of spinosyns A and D in S. spinosa MUV was 244 mg L(-1) and 129 mg L(-1), which was 4.88-fold and 4.77-fold higher than that in the wild-type (50 mg L(-1) and 27 mg L(-1)), respectively. To achieve the better production; positive regulator metK1-sp, rmbA and rmbB genes from Streptomyces peucetius, were expressed and co-expressed in S. spinosa MUV under the control of strong ermE* promoter, using an integration vector pSET152 and expression vector pIBR25, respectively. Herewith, the genetically engineered strain of S. spinosa MUV, produce spinosyns A and D up to 372/217 mg L(-1) that is 7.44/8.03-fold greater than that of wild type. This result demonstrates the use of metabolic engineering on rationally developed high producing natural variants for the production.
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http://dx.doi.org/10.14348/molcells.2014.0168DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4213763PMC
October 2014
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