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Sci Adv 2022 Aug 10;8(32):eabp9929. Epub 2022 Aug 10.

Departments of Molecular Biosciences, Chemistry, and Chemical and Biological Engineering and the Feinberg School of Medicine, Northwestern University, Evanston, IL, USA.

Imaging of proteoforms in human tissues is hindered by low molecular specificity and limited proteome coverage. Here, we introduce proteoform imaging mass spectrometry (PiMS), which increases the size limit for proteoform detection and identification by fourfold compared to reported methods and reveals tissue localization of proteoforms at <80-μm spatial resolution. PiMS advances proteoform imaging by combining ambient nanospray desorption electrospray ionization with ion detection using individual ion mass spectrometry. Read More

Antioxid Redox Signal 2022 Jul 12. Epub 2022 Jul 12.

Central Arkansas Veterans Healthcare System, 19961, Little Rock, Arkansas, United States.

Significance: Nutraceuticals are ingested for health benefits in addition to their general nutritional value. These dietary supplements have become increasingly popular since the late twentieth century and they are a rapidly expanding global industry approaching a half-trillion US dollars annually. Many nutraceuticals are promulgated as potent antioxidants. Read More

In Vivo 2022 Mar-Apr;36(2):543-555

National and Kapodistrian University of Athens, Athens, Greece.

Pancreatic cancer is one of the most fatal malignancies, and therefore, new strategies, which aim at the improvement of the prognosis of this lethal disease, are needed. Many clinical trials have failed to improve overall survival. Nowadays, research is focused on advances provided by novel potential targets to efficiently enhance life expectancy. Read More

Biometals 2022 Mar 1. Epub 2022 Mar 1.

Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.

Despite advances in chemotherapeutic interventions for the treatment of malaria, there is a continuing need for the development of new antimalarial agents. Previous studies indicated that co-administration of chloroquine with antioxidants such as the iron chelator deferoxamine (DFO) prevented the development of persistent cognitive damage in surrogate models of cerebral malaria. The work described herein reports the syntheses and antimalarial activities of covalent conjugates of both natural (siderophores) and artificial iron chelators, namely DFO, ferricrocin and ICL-670, with antimalarial 1,2,4-trioxolanes (ozonides). Read More

Curr Opin Chem Biol 2021 08 8;63:115-122. Epub 2021 Apr 8.

Department of Medicinal Chemistry and Molecular Pharmacology, Purdue Institute for Drug Discovery, Purdue University Center for Cancer Research, Purdue University, 720 Clinic Drive, West Lafayette, IN, 47907, United States. Electronic address:

The posttranslational methylation of the α-N-terminal amino group of proteins was first documented over 40 years ago, but the functional significance of this modification has been underexplored relative to lysine and arginine methylation. Increasing reports implicates α-N-terminal methylation as a widespread and critical regulator of mitosis, chromatin interactions, DNA repair, and translation fidelity. Here, we summarize advances in the current understanding of protein α-N-terminal methylation biological functions and mechanisms across eukaryotic organisms. Read More

BMC Bioinformatics 2020 Dec 3;21(Suppl 9):541. Epub 2020 Dec 3.

Shanghai Key Laboratory for Molecular Imaging, Shanghai University of Medicine and Health Sciences, Shanghai, 201318, People's Republic of China.

Background: Alternative splicing isoforms have been reported as a new and robust class of diagnostic biomarkers. Over 95% of human genes are estimated to be alternatively spliced as a powerful means of producing functionally diverse proteins from a single gene. The emergence of next-generation sequencing technologies, especially RNA-seq, provides novel insights into large-scale detection and analysis of alternative splicing at the transcriptional level. Read More

Lancet Infect Dis 2020 09 9;20(9):e216-e230. Epub 2020 Jul 9.

Reading Hospital, Tower Health, West Reading, PA, USA; Micromoria, Venture X Marlborough, Marlborough, MA, USA. Electronic address:

Accelerating growth and global expansion of antimicrobial resistance has deepened the need for discovery of novel antimicrobial agents. Antimicrobial peptides have clear advantages over conventional antibiotics which include slower emergence of resistance, broad-spectrum antibiofilm activity, and the ability to favourably modulate the host immune response. Broad bacterial susceptibility to antimicrobial peptides offers an additional tool to expand knowledge about the evolution of antimicrobial resistance. Read More

Talanta 2020 Apr 17;210:120645. Epub 2019 Dec 17.

Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556-5670, United States.

Metabolomics, the study of metabolic profiles in a biological sample, has seen rapid growth due to advances in measurement technologies such as mass spectrometry (MS). While MS metabolite reference libraries have been generated for metabolomics applications, mass spectra alone are unable to unambiguously identify many metabolites in a sample; these unidentified compounds are typically annotated as "features". Surface-enhanced Raman spectroscopy (SERS) is an interesting technology for metabolite identification based on vibrational spectra. Read More

Biochim Biophys Acta Biomembr 2020 01 11;1862(1):183062. Epub 2019 Sep 11.

Markey Center for Structural Biology, Department of Biological Sciences, and the Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, 47907, USA. Electronic address:

The β-barrel assembly machinery (BAM) is responsible for the biogenesis of outer membrane proteins (OMPs) into the outer membranes of Gram-negative bacteria. These OMPs have a membrane-embedded domain consisting of a β-barrel fold which can vary from 8 to 36 β-strands, with each serving a diverse role in the cell such as nutrient uptake and virulence. BAM was first identified nearly two decades ago, but only recently has the molecular structure of the full complex been reported. Read More

Methods Mol Biol 2019 ;1934:293-307

Department of Chemistry, Indiana University, Bloomington, IN, USA.

A wide variety of posttranslational modifications of expressed proteins are known to occur in living organisms (Krishna R, Wold F. Post-translational modification of proteins. In: Meister A (ed) Advances in enzymology and related areas of molecular biology. Read More

Adv Mater 2019 Jan 30;31(4):e1804453. Epub 2018 Nov 30.

Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA.

The optimization of traditional electrocatalysts has reached a point where progress is impeded by fundamental physical factors including inherent scaling relations among thermokinetic characteristics of different elementary reaction steps, non-Nernstian behavior, and electronic structure of the catalyst. This indicates that the currently utilized classes of electrocatalysts may not be adequate for future needs. This study reports on synthesis and characterization of a new class of materials based on 2D transition metal dichalcogenides including sulfides, selenides, and tellurides of group V and VI transition metals that exhibit excellent catalytic performance for both oxygen reduction and evolution reactions in an aprotic medium with Li salts. Read More

Biochem Pharmacol 2018 09 22;155:61-70. Epub 2018 Jun 22.

The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA.

The 'neurotrophic sesquiterpenes' refer to a group of molecules derived from the Illicium genus of flowering plant. They display neurotrophic effects in cultured neuron preparations and have been suggested to be cognitive enhancers and potential therapeutics for neurodegenerative disorders and dementias. Recent synthetic advances generated sufficient quantities of jiadifenolide for in vivo investigation into its biological effects. Read More

Proteomics 2018 06 4;18(11):e1700427. Epub 2018 May 4.

Purdue Proteomics Facility, Bindley Biosciences Center, Discovery Park, Purdue University, 1203 W. State Street, 47907, West Lafayette, IN, USA.

Analysis of protein complexes provides insights into how the ensemble of expressed proteome is organized into functional units. While there have been advances in techniques for proteome-wide profiling of cytoplasmic protein complexes, information about human nuclear protein complexes are very limited. To close this gap, we combined native size exclusion chromatography (SEC) with label-free quantitative MS profiling to characterize hundreds of nuclear protein complexes isolated from human glioblastoma multiforme T98G cells. Read More

Adv Biol Chem 2016 Dec 30;6(6):193-215. Epub 2016 Dec 30.

Cancer Therapeutics Program, University of Pittsburgh Cancer Institute, and Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, 5117 Centre Ave., Pittsburgh, PA 15213.

Background: Cervical cancer is the second most common cancer in women worldwide [1]. Photodynamic therapy has been used for cervical intraepithelial neoplasia with good responses, but few studies have used newer phototherapeutics. We evaluated the effectiveness of photodynamic therapy using Pc 4 in vitro and in vivo against human cervical cancer cells. Read More

J Lipid Res 2017 10 28;58(10):2061-2070. Epub 2017 Jul 28.

Weldon School of Biomedical Engineering Purdue University, West Lafayette, IN

Protein post-translational modifications (PTMs) serve to give proteins new cellular functions and can influence spatial distribution and enzymatic activity, greatly enriching the complexity of the proteome. Lipidation is a PTM that regulates protein stability, function, and subcellular localization. To complement advances in proteomic identification of lipidated proteins, we have developed a method to image the spatial distribution of proteins that have been co- and post-translationally modified via the addition of myristic acid (Myr) to the N terminus. Read More

Toxicol In Vitro 2017 Aug 14;42:105-113. Epub 2017 Apr 14.

Fine Particle and Aerosol Technology Laboratory, Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.

Nanomaterials (NM) exhibit novel physicochemical properties that determine their interaction with biological substrates and processes. Recent nano-technological advances are leading to wide usage of metallic nanoparticles (NPs) in various fields. However, the increasing use of NPs has led to their release into environment and the toxicity of NPs on human health has become a concern. Read More

Adv Biol Chem 2017 Apr 25;7(2):89-106. Epub 2017 Apr 25.

Department of Chemistry, Saint Michael's College, Colchester, Vermont, USA.

Calmodulin from is an α-helical calcium-binding protein that expresses to high levels in . When the N-terminus of a calmodulin variant is bound to Ca, it undergoes a conformational change, exposing hydrophobic pockets. This property can be utilized for purification purposes, as these pockets bind to phenyl sepharose resin with high affinity. Read More

J Intern Med 2017 03 22;281(3):233-246. Epub 2016 Nov 22.

Department of Chemistry, Indiana University Bloomington, Bloomington, IN, USA.

Fibroblast growth factor (FGF) 21 belongs to a hormone-like subgroup within the FGF superfamily. The members of this subfamily, FGF19, FGF21 and FGF23, are characterized by their reduced binding affinity for heparin that enables them to be transported in the circulation and function in an endocrine manner. It is likely that FGF21 also acts in an autocrine and paracrine fashion, as multiple organs can produce this protein and its plasma concentration seems to be below the level necessary to induce a pharmacological effect. Read More

J Pept Sci 2016 May 22;22(5):260-70. Epub 2016 Feb 22.

Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN, 47405, USA.

The synthesis of insulin has inspired fundamental advances in the art of peptide science while simultaneously revealing the structure-function relationship of this centrally important metabolic hormone. This review highlights milestones in the chemical synthesis of insulin that can be divided into two separate approaches: (i) disulfide bond formation driven by protein folding and (ii) chemical reactivity-directed sequential disulfide bond formation. Common to the two approaches are the persistent challenges presented by the hydrophobic nature of the individual A-chain and B-chain and the need for selective disulfide formation under mildly oxidative conditions. Read More

Anal Bioanal Chem 2016 Apr 18;408(11):2649-58. Epub 2016 Jan 18.

Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA.

Because noncovalent interface functionalization is frequently required in graphene-based devices, biomolecular self-assembly has begun to emerge as a route for controlling substrate electronic structure or binding specificity for soluble analytes. The remarkable diversity of structures that arise in biological self-assembly hints at the possibility of equally diverse and well-controlled surface chemistry at graphene interfaces. However, predicting and analyzing adsorbed monolayer structures at such interfaces raises substantial experimental and theoretical challenges. Read More

Adv Biol Chem 2015 Jun;5:179-188

Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA.

Prepore formation is hypothesized to be an obligate step in the insertion of Cry1Ab toxin into insect brush border membrane vesicles. We examined the architecture of the putative prepore when isolated using the published protocols [1] [2]. Our results demonstrate that the putative prepore form of Cry1Ab is a combination of receptor proteins attached to the toxin, when purified. Read More

Biosens Bioelectron 2016 Feb 3;76:234-42. Epub 2015 Jun 3.

Department of Nanoengineering, University of California San Diego, San Diego, CA 92903, USA. Electronic address:

Self-propelled nanomotors offer considerable promise for developing novel biosensing protocols involving 'on-the-fly' recognition events. This article reviews recent advances in using catalytic nanomotors for bioaffinity sensing and for isolating target biomolecules and cells from complex biological samples. A variety of receptors, attached to self-propelled nanoscale motors, can thus move around the sample and, along with the generated microbubbles, lead to greatly enhanced fluid transport and accelerated recognition process. Read More

Adv Biol Chem 2015;5(7). Epub 2015 Dec 16.

Department of Chemistry and Biochemistry, California State University Northridge, Northridge, CA, USA.

During Nucleotide Excision Repair (NER) in the yeast , ubiquitylation of Rad4 is carried out by the E3 ubiquitin ligase that includes Rad7-Elc1-Cul3 and is critical to optimal NER. Rad7 E3 activity targets Rad4 for degradation by the proteaseome but, in principle, could also trigger other DNA damage responses. We observed increased nuclear ubiquitin foci (Ub-RFP) formation in containing a Rad7 E3 ligase mutant () in response to DNA damage by benzo[a]pyrenediolepoxide (BPDE) in dividing cells. Read More

Electrophoresis 2014 Dec 10;35(24):3430-40. Epub 2014 Jul 10.

Department of Biochemistry, Purdue University, West Lafayette, IN, USA.

Phosphoproteomics is the systematic study of one of the most common protein modifications in high throughput with the aim of providing detailed information of the control, response, and communication of biological systems in health and disease. Advances in analytical technologies and strategies, in particular the contributions of high-resolution mass spectrometers, efficient enrichments of phosphopeptides, and fast data acquisition and annotation, have catalyzed dramatic expansion of signaling landscapes in multiple systems during the past decade. While phosphoproteomics is an essential inquiry to map high-resolution signaling networks and to find relevant events among the apparently ubiquitous and widespread modifications of proteome, it presents tremendous challenges in separation sciences to translate it from discovery to clinical practice. Read More

Adv Biol Chem 2013 Aug;3(4):389-396

Department of Pharmacology and Toxicology, Morehouse School of Medicine, Atlanta, USA.

The benzenearsonate, Roxarsone, has been used since 1944 as an antimicrobial, growth-promoting poultry feed additive. USGS and EPA report that Roxarsone (4-hydroxy-3-nitrobenzenearsonate) and metabolites, including AHBA (3-amino-4-hydroxybenzenearsonate), contaminate waterways at greater than 1100 tons annually. To assess human impact of these organic arsenic water contaminants, it was important to study their potential absorption. Read More

Adv Biol Chem 2013 Jun;3(3):295-303

Department of Chemistry and Biochemistry, California State University Northridge, Northridge, USA.

Several modes of eukaryotic of DNA double strand break repair (DSBR) depend on synapsis of complementary DNA. The Rad51 ATPase, the homolog of RecA, plays a key role in this process by catalyzing homology searching and strand exchange between an invading DNA strand and a repair template (e.g. Read More

Adv Biol Chem 2012 Aug;2(3):218-225

Department of Chemistry and Biochemistry, California State University Northridge, Northridge, USA.

Background: Insulin resistance is linked to dyslipidemia, characterized by a decrease in high density lipoproteins and an increase in low density lipoproteins. Thiazolidinediones (TZDs) are insulin-sensitizing agents used to improve glycemic control in patients with type 2 diabetes. Recently, the safety of certain TZD regimens has been questioned because of associated adverse effects on the plasma lipid profile. Read More

Glycoconj J 2013 Feb 4;30(2):89-117. Epub 2012 Sep 4.

Department of Chemistry, Indiana University, Bloomington, IN, USA.

This review summarizes the analytical advances made during the last several years in the structural and quantitative determinations of glycoproteins in complex biological mixtures. The main analytical techniques used in the fields of glycomics and glycoproteomics involve different modes of mass spectrometry and their combinations with capillary separation methods such as microcolumn liquid chromatography and capillary electrophoresis. The need for high-sensitivity measurements have been emphasized in the oligosaccharide profiling used in the field of biomarker discovery through MALDI mass spectrometry. Read More

Expert Opin Drug Discov 2012 May 22;7(5):417-28. Epub 2012 Mar 22.

Department of Biological Sciences, Bindley Bioscience Center, Purdue University, IN, USA.

Introduction: The members of the family Flaviviridae, including West Nile virus, yellow fever virus and dengue virus, are important human pathogens that are expanding their impact around the globe. The four serotypes of dengue infect 50-100 million people each year, yet the only clinical treatment is supportive care to reduce symptoms. Drugs that employ novel inhibition mechanisms and targets are urgently needed to combat the growing incidence of dengue worldwide. Read More

Heredity (Edinb) 2010 Jan;104(1):79-87

Department of Biological Sciences, Purdue University, West Lafayette, IN, USA.

Recent advances in the statistical analysis of microsatellite data permit calculation of sex-specific dispersal rates through sex- and age-specific comparisons of genetic variation. This approach, developed for the analysis of data derived from co-dominant autosomal markers, should be applicable to a sex-specific marker such as mitochondrial DNA. To test this premise, we amplified a 449 bp control region DNA sequence from the mitochondrial genome of the collared peccary (Pecari tajacu), and estimated intra-class correlations among herds sampled from three Texas populations. Read More