Publications by authors named "Archit Gupta"

19 Publications

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HU-AB simulacrum: Fusion of HU-B and HU-A into HU-B-A, a functional analog of the Escherichia coli HU-AB heterodimer.

Biochem Biophys Res Commun 2021 Jun 5;560:27-31. Epub 2021 May 5.

Centre for Protein Science, Design and Engineering (CPSDE), Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector-81, SAS Nagar, Punjab, 140306, India. Electronic address:

In enteric bacteria such as Escherichia coli, there are two homologs of the DNA-binding nucleoid associated protein (NAP) known as HU. The two homologs are known as HU-A and HU-B, and exist either in the form of homodimers (HU-AA, or HU-BB) or as heterodimers (HU-AB), with different propensities to form higher-order oligomers. The three different dimeric forms dominate different stages of bacterial growth, with the HU-AB heterodimer dominating cultures in the stationary phase. Due to similarities in their properties, and the facile equilibrium that exists between the dimeric forms, the dimers are difficult to purify away from each other. Although HU-AA and HU-BB can be purified through extensive ion-exchange chromatography, reestablishment of equilibrium interferes with the purification of the HU-AB heterodimer (which constitutes ∼90% of any population with equal numbers of HU-B and HU-A chains). Here, we report the creation of a functional analog of HU-AB that does not appear to partition to generate any minority populations of HU-AA or HU-BB. The analog was constructed through genetic fusion of the HU-B and HU-A chains into a single polypeptide (HU-B-A) with a glycine/serine-rich linker of 11 amino acids separating HU-B from HU-A, and a histidine tag at the N-terminus of HU-B. HU-B-A folds to bind 4-way junction DNA, and displays a significant tendency to form dimers (i.e., analogs of HU tetramers), and a higher thermodynamic stability than HU-BB or HU-AA, thus explaining why it dominates mixtures of HU-B and HU-A chains.
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http://dx.doi.org/10.1016/j.bbrc.2021.04.107DOI Listing
June 2021

The DNA-binding protein HU is a molecular glue that attaches bacteria to extracellular DNA in biofilms.

J Biol Chem 2021 Mar 10:100532. Epub 2021 Mar 10.

Centre for Protein Science, Design and Engineering (CPSDE), Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector-81, SAS Nagar, Punjab, 140306. Electronic address:

In biofilms, bacteria that possess a negatively-charged surface are embedded within a matrix of polymers consisting mainly of negatively-charged extracellular DNA (e-DNA). In all likelihood, a multivalent positively-charged substance, e.g., a basic protein, exists within biofilms to neutralize charge-charge repulsions and act as a 'glue' attaching negatively-charged bacteria to negatively-charged e-DNA; however, no protein capable of doing so has yet been identified. We decided to investigate whether a highly-abundant nucleoid-associated protein (HU) happens to be the glue in question. In recent years, HU has been shown to possess qualities that could be considered desirable in the proposed glue, e.g., (a) availability in association with e-DNA; (b) multivalent DNA-binding; (c) non-sequence-specific DNA-binding; (d) enhancement of biofilm formation upon exogenous addition, and (e) disruption of biofilms, upon removal by HU-cognate antibodies. Geometric considerations suggest that basic residues in HU's canonical and non-canonical DNA-binding sites can interact with sugar-linked terminal phosphates in lipopolysaccharide (LPS) molecules in bacterial outer membranes. Here, using genetic, spectroscopic, biophysical-chemical, microscopy-based and cytometry-based experiments, we demonstrate that HU's DNA-binding sites also bind to LPS; that this facilitates DNA-DNA, DNA-LPS and LPS-LPS interactions; and that this facilitates bacterial clumping as well as attachment of bacteria to DNA. Exogenous addition of HU to bacteria in (non-shaken) cultures is shown to cause cells to become engulfed in a matrix of DNA, potentially arising from the lysis of bacteria with vulnerable cell walls (as they strain to grow, divide and move away from each other, in opposition to the accreting influence of HU).
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http://dx.doi.org/10.1016/j.jbc.2021.100532DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8063757PMC
March 2021

A novel protein-engineered dsDNA-binding protein (HU-Simulacrum) inspired by HU, a nucleoid-associated DNABII protein.

Biochem Biophys Res Commun 2021 01 10;534:47-52. Epub 2020 Dec 10.

Centre for Protein Science, Design and Engineering (CPSDE), Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Mohali, Knowledge City, Sector-81, SAS Nagar, Punjab, 140306, India. Electronic address:

HU, a DNA-binding protein, has a helical N-terminal region (NTR) of ∼44 residues and a beta strand- and IDR-rich C-terminal region (CTR) of ∼46 residues. CTR binds to DNA through (i) a clasp (two arginine/lysine-rich, IDR-rich beta hairpins that bind to phosphate groups in the minor groove), (ii) a flat surface (comprising four antiparallel beta strands that abut the major groove), and (iii) a charge cluster (two lysine residues upon a short C-terminal helix). HU forms a dimer displaying extensive inter-subunit CTR-CTR contacts. A single-chain simulacrum of these contacts (HU-Simul) incorporating all DNA-binding elements was created by fusing together the CTRs of Escherichia coli HU-A and Thermus thermophilus HU. HU-Simul is monomeric, binds to dsDNA and cruciform DNA, but not to ssDNA.
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http://dx.doi.org/10.1016/j.bbrc.2020.11.088DOI Listing
January 2021

Abdominal compartment syndrome secondary to myxedema ileus.

Ci Ji Yi Xue Za Zhi 2020 Apr-Jun;32(2):219-221. Epub 2019 Apr 23.

Department of General Surgery, IGMC, Shimla, Himachal Pradesh, India.

Acute pseudo-obstruction of the colon is known as Ogilvie syndrome (OS). There are varied causes of OS. Myxedema ileus (MI) as a cause of acute pseudo-obstruction is rare. Surgery in cases of MI is reserved only in cases of cecal distension of >12 cm, bowel ischemia, and perforated bowel. We present a rare case of a 71-year-old female who was operated for abdominal compartment syndrome secondary to MI.
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http://dx.doi.org/10.4103/tcmj.tcmj_31_19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7137358PMC
April 2019

Ruptured primary mucinous cystadenoma of spleen leading to mucinous ascites.

BMJ Case Rep 2019 Nov 21;12(11). Epub 2019 Nov 21.

General Surgery, Indira Gandhi Medical College, Shimla, India

Mucinous cystadenoma are rare benign mucin-producing tumours. Primary mucinous neoplasms most commonly involve ovary, pancreas or appendix. They may rupture to produce mucous ascites/pseudomyxoma peritonei. We are describing a 51-year-old man who presented to us with symptomatic gallstone disease but during preoperative ultrasound was found to have cystic lesions in spleen with free fluid in the abdomen. Splenectomy and drainage of mucin were done. Histopathology was done and a final diagnosis of primary mucinous cystadenoma of spleen with mucinous ascites was made.
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http://dx.doi.org/10.1136/bcr-2019-231212DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6887401PMC
November 2019

Diffuse normolipemic plane xanthoma with underlying photosensitive dermatoses.

BMJ Case Rep 2019 Nov 2;12(11). Epub 2019 Nov 2.

Surgery, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India

Diffuse plane xanthomatosis is a normolipemic non-Langerhan cell histiocytosis. Clinically, patient presents as asymptomatic yellowish plaques involving eyelids, neck, upper trunk and flexures. Usually, there is an associated haematological or lymphoproliferative malignancy which may precede or follow dermatological manifestations by many years. Rarely inflammatory dermatosis like atopic eczema, photosensitive dermatosis, erythroderma, previous scars and lymphoedema have been found to be associated with these xanthomas. We are reporting a 46-year-old male patient who had a history of photosensitivity for the last 15 years and subsequently developed diffuse plane normolipemic xanthomas.
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http://dx.doi.org/10.1136/bcr-2019-230720DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6827770PMC
November 2019

Intraperitoneal bladder explosion during transurethral surgery.

BMJ Case Rep 2019 Jul 12;12(7). Epub 2019 Jul 12.

General Surgery, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India.

Transurethral resection of prostate (TURP) is the most common operation performed for obstruction secondary to prostatic enlargement. Though considered as a safe procedure, occasionally life-threatening complications may be seen. Intravesical explosion, secondary to ignition by diathermy of the accumulated mixture of hydrogen, hydrocarbons and higher concentration of oxygen, is a rarely reported complication (only 38 cases reported until). We are reporting a 60-year-old man suffering from benign prostatic hyperplasia in whom during TURP bladder explosion occurred which was suspected early and immediately explored and repaired leading to a favourable outcome.
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http://dx.doi.org/10.1136/bcr-2019-229580DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6626441PMC
July 2019

Parkes Weber syndrome presenting as Stewart-Bluefarb acroangiodermatitis.

BMJ Case Rep 2019 Mar 8;12(3). Epub 2019 Mar 8.

Department of General Surgery, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India.

Parkes Weber syndrome (PWS) is a rare disorder characterised by arteriovenous (AV) fistula, along with capillary, lymphatic, venous malformations and limb hypertrophy. Stewart-Bluefarb syndrome is a variant of acroangiodermatitis, which is associated with congenital AV malformation/fistulas. It usually begins early in life, unilaterally over lower extremities presenting as violaceous to dusky coloured macules, papules or plaques with tendency to ulcerate. We are reporting a case of AV malformation fulfilling the triad of PWS and presenting with acroangiodermatitis.
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http://dx.doi.org/10.1136/bcr-2018-227793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6424474PMC
March 2019

Aggressive Digital Papillary Adenocarcinoma at Atypical Site.

Clin Med Insights Case Rep 2019 7;12:1179547619828723. Epub 2019 Feb 7.

Department of General Surgery, Indira Gandhi Medical College, Shimla, India.

Aggressive digital papillary adenocarcinoma (ADPA) is a rare tumour of eccrine origin. They present as asymptomatic nodules with flattened and thickened surface skin, most commonly on fingers and toes. It mimics many benign entities and tumours, hence leading to a delay in diagnosis. It has a high metastasizing potential, but is slowly progressive. Histopathologically, it has both a nodular and a cystic component with papillary projections into cystic spaces. We present a 54-year man with a tumorous mass on right heel, which was diagnosed by histopathology and immunohistochemistry as ADPA. Our case had ADPA lesion, a rarely reported malignancy on an uncommon site with distant metastasis.
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http://dx.doi.org/10.1177/1179547619828723DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6376506PMC
February 2019

Idiopathic tumoral calcinosis presenting in early childhood.

BMJ Case Rep 2019 Jan 24;12(1). Epub 2019 Jan 24.

Department of Surgery, Indira Gandhi Medical College, Shimla, Himachal pradesh, India.

Idiopathic calcinosis (IC) is deposition of calcium hydroxyapatite crystals or amorphous calcium with no predisposing cause. IC presents in juxta-articular tissue in a tumour-like fashion is known as idiopathic tumoral calcinosis (ITC). Recurrent trauma and chronic pressure are thought to be the triggering factors. It usually presents in adolescents and adults. Presentation in early childhood is a rarity. We are reporting ITC in an 8-year-old child with the onset at 4 years of age.
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http://dx.doi.org/10.1136/bcr-2018-227083DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6347933PMC
January 2019

Dyskeratosis congenita: presentation of cutaneous triad in a sporadic case.

BMJ Case Rep 2018 Nov 28;11(1). Epub 2018 Nov 28.

Department of Surgery, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India.

Dyskeratosis congenita (DKC) also known as Zinsser-Cole-Engman syndrome is a progressive genetic disease with a classical presentation characterised by a triad of reticulate pigmentation of skin, nail dystrophy and leukoplakia. It may be a multisystem disease with the involvement of haematological, gastrointestinal, genitourinary, neurological, ophthalmic, pulmonary and skeletal system. We report a sporadic case of DKC presenting with poikiloderma, nail dystrophy and oral leukoplakia.
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http://dx.doi.org/10.1136/bcr-2018-226736DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301648PMC
November 2018

Single-incision laparoscopic cholecystectomy using conventional instruments in situs inversus totalis.

BMJ Case Rep 2018 Nov 28;11(1). Epub 2018 Nov 28.

Department of Surgery, Indira Gandhi Medical College, Shimla, India.

Situs inversus totalis is a rare genetic disorder. Single-incision laparoscopic cholecystectomy (SILC) in situs inversus totalis has been reported rarely. SILC has an advantage of being easier than conventional laparoscopic cholecystectomy in addition to better cosmesis and reduced postoperative pain. We report a case of single-incision laparoscopic cholecystectomy done in a young woman with situs inversus totalis using conventional laparoscopic instruments.
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http://dx.doi.org/10.1136/bcr-2018-226404DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301540PMC
November 2018

Hypomelanosis of Ito with gynaecomastia and dental anomaly.

BMJ Case Rep 2018 Jul 6;2018. Epub 2018 Jul 6.

Department of Surgery, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India.

Hypomelanosis of Ito is a rare neurocutaneous syndrome. Cutaneous involvement is characterised by streaks and swirls of hypopigmentation arranged in a Blaschkoid pattern. Neural involvement along with other systemic features are seen. We report a case of a 13-year-old boy who presented with the characteristic skin involvement of hypomelanosis of Ito, mental retardation, teeth abnormalities and gynaecomastia along with psoriasis.
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http://dx.doi.org/10.1136/bcr-2018-225055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6040523PMC
July 2018

Transverse testicular ectopia with persistent mullerian duct syndrome.

BMJ Case Rep 2018 Apr 18;2018. Epub 2018 Apr 18.

Department of Surgery, Indira Gandhi Medical College, Shimla, India.

Persistent mullerian duct syndrome (PMDS) is a rare form of male pseudohermaphroditism caused by defects in synthesis or actions of mullerian inhibiting factor characterised by persistence of mullerian duct structures in a normal karyotype male. Transverse testicular ectopia (TTE) is a rare disease in which both testes are located in the same inguinal canal. We report a case of PMDS with TTE in a 1-year-old child who presented with non-palpable testis on right side with hernia on left side. Left herniotomy with bilateral trans-septal orchidopexy was done in this patient.
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http://dx.doi.org/10.1136/bcr-2017-223994DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5911094PMC
April 2018

Primary apocrine carcinoma of an unusual site.

BMJ Case Rep 2017 Dec 20;2017. Epub 2017 Dec 20.

Department of General Surgery, Indira Gandhi Medical College, Shimla, India.

Primary apocrine carcinoma is a rare malignancy most commonly occurring in apocrine dense areas like axilla. There are only about 200 cases reported to date. We report a case of primary apocrine carcinoma present at an unusual site, that is, the arm. A wide local excision of the mass was done and was diagnosed as apocrine carcinoma on histopathological examination and was confirmed by immunohistochemistry. Wide local excision is the treatment required.
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http://dx.doi.org/10.1136/bcr-2017-222558DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5743890PMC
December 2017

Primary cutaneous mucoepidermal carcinoma.

BMJ Case Rep 2017 Nov 29;2017. Epub 2017 Nov 29.

Department of Surgery, Indira Gandhi Medical College, Shimla, India.

Mucoepidermal carcinoma (MEC) is a tumour having mixed components of mucus secreting and epidermoid cells. Salivary glands are the the most common site of origin. Primary cutaneous MEC is a rare presentation. We report a primary cutaneous MEC in a 98-year-old woman presenting a noduloulcerative lesion over the dorsum of the nose. Histopathology of the tumour showed nests of epidermoid cells with glandular differentiation and mucin production. The diagnosis was confirmed by immunohistochemistry.
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http://dx.doi.org/10.1136/bcr-2017-223080DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5720310PMC
November 2017

Primary renal echinococcosis with gross hydatiduria.

BMJ Case Rep 2017 Aug 24;2017. Epub 2017 Aug 24.

Department of General Surgery, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India.

Renal echinococcosis is a rare disease. It is usually asymptomatic but may present with pain, lump or in rare cases hydatiduria. Diagnosis is mainly by imaging but serology is usually false negative. We present a patient of renal echinococcosis who presented with passing of grape skin like structures in urine and was diagnosed to be a case of renal echinococcosis on the basis of positive serology, ultrasonographic and CT findings. The patient underwent a nephroureterectomy and was given albendazole preoperatively and postoperatively.
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http://dx.doi.org/10.1136/bcr-2017-220502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5623262PMC
August 2017

Unusual Case of Bilateral Tubercular Mastitis.

Cureus 2017 Jun 22;9(6):e1383. Epub 2017 Jun 22.

General Surgery, Indira Gandhi Medical College, Shimla.

Bilateral involvement of the breast with tuberculosis is extremely rare. It most commonly affects young lactating multiparous females, although rarely it may be reported in prepubescent males also. We present a case of a 27-year-old nulliparous female who presented with a history of multiple pus discharging sinuses around both areolae and was diagnosed as a case of bilateral tubercular mastitis. Tubercular mastitis being a paucibacillary disease, diagnosis is often difficult. Treatment consists of antitubercular therapy with or without surgery.​.
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http://dx.doi.org/10.7759/cureus.1383DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5522020PMC
June 2017

Sociodemographic characteristics and aggression quotient among children in conflict with the law in India: A case-control study.

Natl Med J India 2015 Jul-Aug;28(4):172-5

Department of Internal Medicine, Armed Forces Medical College, Pune 411040, Maharashtra, India.

Background: The incidence of juvenile delinquency has increased in the past decade in India and juvenile crimes are increasingly being reported. This has been attributed to many biopsychosocial factors. It is essential to understand these issues in the context of India to determine the response of acts of children in conflict with the law. We aimed to assess the sociodemographic characteristics and the aggression quotient of children in conflict with the law (juvenile delinquents) in observation homes across India and compare them with those who were not.

Methods: We did a case-control study in five juvenile homes in the cities of Hyderabad, Lucknow and Pune. Ninety inmates (74 boys, 16 girls) were included in the study. Sociodemographic characteristics and aggression quotient of children in conflict with the law were evaluated using two separate questionnaires, i.e. a sociodemographic questionnaire and the modified Buss and Perry aggression questionnaire. These were compared with a control group of similar age, sex and income status.

Results: All the children in conflict with the law surveyed belonged to the lower socioeconomic strata, had a significantly higher chance (p<0.05) of coming from broken homes, have addictions, jailed family members and suffered physical and sexual abuse than controls. They also scored higher on all domains of the aggression questionnaire than controls.

Conclusion: A collection of sociodemographic attributes such as broken homes, addictions and abuse seem to have an important association with juvenile delinquency. Children in conflict with the law are also more likely to be associated with a higher aggression quotient as compared to children who were not.
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May 2016