@article { ISI:000244404400002, title = {Characterization of the proteins of bacterial strain isolated from contaminated site involved in heavy metal resistance - a proteomic approach}, journal = {Journal of Biotechnology}, volume = {128}, number = {3}, year = {2007}, month = {FEB}, pages = {444-451}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The present study describes response of a bacterial strain isolated from a polluted river to heavy metal toxicity. The bacterium was identified to be Klebsiella pneumoniae by biochemical tests using API 20E strips and 16S ribotyping. The isolate was studied for its tolerance to two heavy metals, i.e., cobalt (Co2+) and lead (Pb2+) by growing it in citrate mineral medium (CMM). Proteomic approach involving two-dimensional polyacrylamide gel electrophoresis (2D PAGE) and mass spectrometry (MS) was used to identify the differentially expressed proteins under heavy metal stress. Two of the differentially expressed proteins were identified to be L-isoaspartate protein carboxymethyltransferase type II and DNA gyrase A. To our knowledge, this is for the first time that K pneumoniae has been reported to be present in metal contaminated site and L-isoaspartate protein carboxymethyltransferase type II protein to be over expressed under heavy metal stress. The role of these proteins in metal tolerance is discussed. (c) 2006 Elsevier B.V. All rights reserved.

}, keywords = {2D PAGE, heavy metal toxicity, Mass spectrometry}, issn = {0168-1656}, doi = {10.1016/j.jbiotec.2006.11.010}, author = {Bar, Chinmayee and Patil, Rajendra and Doshi, Jignesh and Kulkarni, Mahesh J. and Gade, Wasudeo N.} } @article { ISI:000264127100020, title = {Column liquid chromatography-ultraviolet and column liquid chromatography/mass spectrometry evaluation of stress degradation behavior of escitalopram oxalate}, journal = {Journal of AOAC international}, volume = {92}, number = {1}, year = {2009}, month = {JAN}, pages = {138-147}, abstract = {

{The objective of this work was to study the degradation behavior of escitalopram oxalate under different International Conference on Harmonization (ICH)-recommended stress conditions by column liquid chromatography (LC)-UV and LC/mass spectrometry (LC/MS) and to establish a validated stability-indicating LC assay method. Escitalopram oxalate was subjected to stress conditions of hydrolysis, oxidation, photolysis, and thermal decomposition. Extensive degradation was found to occur in alkaline medium. Mild degradation was observed in acidic and oxidative conditions. Escitalopram oxalate was stable to neutral, photolytic, and thermal stress. Successful separation of the drug from degradation products formed under stress conditions was achieved on a PerfectSil-100 ODS-3 column [C(18) (5 mu m, 25 cm x 4.6 mm id)] using methanol-0.01 M acetate buffer pH 3.8 adjusted with acetic acid (45 + 55) as the mobile phase. The flow rate was 1 mL/min, and the detection wavelength was 239 nm. The method was validated according to ICH guidelines. Major degradation products formed in hydrolysis and oxidative conditions were isolated, and structural elucidation of degradation products was done by LC/MS and infrared spectrometry studies. The major hydrolysis degradation product was confirmed as 1-(3-dimethylaminopropyl)-1-(4-fluoro-phenyl)-1,3dihydroisobenzofuran-5- carboxylic acid, and the major oxidative degradation product was confirmed as 1-{[3-dimethylamino(oxide)-propyl]-1(4-flurophenyl)}-1,3-dihydro-iso benzofuran-5-carbonitrile.

}, author = {Dhaneshwar, Sunil R. and Mahadik, Mahadeo V. and Kulkarni, Mahesh J.} } @article { ISI:000297606200009, title = {Comparative and chemical proteomic approaches reveal gatifloxacin deregulates enzymes involved in glucose metabolism}, journal = {Journal of Toxicological Sciences}, volume = {36}, number = {6}, year = {2011}, month = {DEC}, pages = {787-796}, publisher = {JAPANESE SOC TOXICOLOGICAL SCIENCES}, address = {INTERNATIONAL MEDICAL INFORMATION CENTER, SHINANOMACHI RENGAKAN, 35 SHINANO-MACHI, SHINJUKU-KU, TOKYO, 160-0016, JAPAN}, abstract = {

Gatifloxacin has been associated with increased risks of hypoglycemic and hyperglycemic side effects. In order to understand the molecular mechanism of gatifloxacin induced deregulation of glucose metabolism, a Combination of comparative and chemical proteomic approaches were employed using yeast as a model system. Differential protein expression studies using two dimensional electrophoresis and mass spectrometry reveal that gatifloxacin deregulates the expression of key enzymes involved in glucose metabolism. Furthermore, affinity chromatography and LC-MSE analysis led to identification of enolase, as one of the key gatifloxacin binding proteins. Fluorescence spectrometric studies confirmed that the gatifloxacin indeed binds to enolase. Role of enolase in regulation of gatifloxacin induced dysglycemic effect is discussed.

}, keywords = {antibiotics, Differential protein expression, Fluoroquinolone, Glycolysis, Yeast}, issn = {0388-1350}, doi = {10.2131/jts.36.787}, author = {Suresh, Kesavan K. and Bhosale, Santosh D. and Thulasiram, Hirekodathakallu V. and Kulkarni, Mahesh J.} } @article { ISI:000342018100001, title = {Cholesterol depletion by methyl-beta-cyclodextrin augments tamoxifen induced cell death by enhancing its uptake in melanoma}, journal = {Molecular Cancer}, volume = {13}, year = {2014}, month = {SEP}, pages = {Article No. 204}, publisher = {BIOMED CENTRAL LTD}, type = {Article}, address = {236 GRAYS INN RD, FLOOR 6, LONDON WC1X 8HL, ENGLAND}, abstract = {

Background: Despite modern advances in treatment, skin cancer is still one of the most common causes of death in the western countries. Chemotherapy plays an important role in melanoma management. Tamoxifen has been used either alone or in-combination with other chemotherapeutic agents to treat melanoma. However, response rate of tamoxifen as a single agent has been comparatively low. In the present study, we investigated whether treatment with methyl-beta-cyclodextrin (MCD), a cholesterol depleting agent, increases the efficacy of tamoxifen in melanoma cells. Methods: This was a two-part study that incorporated in vitro effects of tamoxifen and MCD combination by analyzing cell survival, apoptosis and cell cycle analysis and in vivo antitumor efficacy on tumor isografts in C57BL/6J mice. Results: MCD potentiated tamoxifen induced anticancer effects by causing cell cycle arrest and induction of apoptosis. Sensitization to tamoxifen was associated with down regulation of antiapoptotic protein Bcl-2, up-regulation of proapoptotic protein Bax, reduced caveolin-1 (Cav-1) and decreased pAkt/pERK levels. Co-administration of tamoxifen and MCD caused significant reduction in tumor volume and tumor weight in mice due to enhancement of drug uptake in the tumor. Supplementation with cholesterol abrogated combined effect of tamoxifen and MCD. Conclusion: Our results emphasize a potential synergistic effect of tamoxifen with MCD, and therefore, may provide a unique therapeutic window for improvement in melanoma treatment.

}, keywords = {Caveolin-1, Cholesterol, Methyl beta-cyclodextrin, Tamoxifen}, issn = {1476-4598}, doi = {10.1186/1476-4598-13-204}, author = {Mohammad, Naoshad and Malvi, Parmanand and Meena, Avtar Singh and Singh, Shivendra Vikram and Chaube, Balkrishna and Vannuruswamy, Garikapati and Kulkarni, Mahesh J. and Bhat, Manoj Kumar} } @article {44430, title = {Chemo-biological evaluation of antidiabetic activity of M entha arvensis L. and it{\textquoteright}s role in inhibition of advanced glycation end products}, journal = {Journal of Ayurveda and integrative medicine}, year = {2018}, month = {FEB}, abstract = {

Background: There has been enormous curiosity in the development of alternative plant based medicines to control diabetes, oxidative stress and related disorders. One of the therapeutic approaches is to reduce postprandial release of glucose in the blood. Two key enzymes that are involved in reducing postprandial glucose are α-amylase and α-glucosidase. Mentha arvensis L. has been traditionally used by several tribes as a medicinal plant to treat various disorders. Objective: The present study was undertaken to test M. arvenisis L. for inhibition of postprandial hyperglycemia. Material and method: We performed various in vitro and in vivo tests to evaluate efficacy of M. arvenisis L. for antidiabetic activity (postprandial hyperglycemia). Results: Methanolic extract of M. arvensis L. leaves showed DPPH free radical scavenging activity (more than 78\% μg/μl) and high antiglycation potential (more than 90\% inhibition of AGE formation). Methanolic extract also showed remarkable inhibitory effects on α-amylase (more than 50\% μg/μl) and α-glucosidase (68\% μg/μl) and significant inhibition of postprandial hyperglycemia in starch induced diabetic Wistar rats. Conclusion: The non-insulin dependent antidiabetic or inhibition of postprandial hyperglycemic activity of methanolic extract of M. arvensis L. leaves was shown by using in vitro and in vivo approaches in the present study.

}, doi = {10.1016/j.jaim.2017.07.003}, author = {Agawane, Sachin B. and Gupta, Vidya S. and Kulkarni, Mahesh J. and Bhattacharya, Asish K. and Koratkar, Santosh} } @article {46685, title = {CD44, a predominant protein in methylglyoxal-induced secretome of muscle cells, is elevated in diabetic plasma}, journal = {ACS Omega}, volume = {5}, year = {2020}, month = {OCT }, pages = {25016-25028}, type = {Article}, abstract = {

Methylglyoxal (MG), a glycolytic intermediate and reactive dicarbonyl, is responsible for exacerbation of insulin resistance and diabetic complication. In this study, NIG-induced secretome of rat muscle cells was identified and relatively quantified by SWATH-MS. A total of 643 proteins were identified in MG induced{\textquoteright} secretome, of which 82 proteins were upregulated and 99 proteins were downregulated by more than 1.3-fold in SWATH analysis. Further, secretory proteins from the dassical secretory pathway and nonclassical secretory pathway were identified using SignalP and SecretomeP, respectively. A total of 180 proteins were identified with SignalP, and 113 proteins were identified with SecretomeP. The differentially expressed proteins were functionallyannotated by KEGG pathway analysis using Cytoscape soft ware with plugin clusterMaker. The differentially expressed proteins were{\textquoteright}sfound to he involved m various pathways like extracellular matrix (ECM) receptor interaction, leukocyte transendothelial migration, fluid shear tress and atherosclerosis, complement and coagulation cascades, and lysosomal pathway. Since the MG levels are high in diabetic conditions, the presence of MG-induced isecreted proteins was inspected {\textquoteleft}by profiling human plasma of healthy and diabetic subjects (n = 10 each). CD44, a predominant MG -induced secreted protein, was found to be elevated in the diabetic plasma and to have a role in the development of insulin resistance.

}, issn = {2470-1343}, doi = {10.1021/acsomega.0c01318}, author = {Bai, Shakuntala and Chaurasiya, Arvindkumar H. and Banarjee, Reema and Walke, Prachi B. and Rashid, Faraz and Unnikrishnan, Ambika G. and Kulkarni, Mahesh J.} } @article {47449, title = {Comparison of glycoprofiles of rituximab versions licensed for sale in India and an analytical approach for quality assessment}, journal = {Journal of Proteomics }, volume = {244}, year = {2021}, month = {JUL}, pages = {104267}, type = {Article}, abstract = {

Glycosylation affects clinical efficacy and safety; therefore, is a critical quality attribute of therapeutic monoclonal antibodies. Glycans are often labile and complex in patterns, giving rise to macro- and micro-heterogeneity. Recombinant production, diverse geographical locations, associated transportation and storage conditions further compound the problem. Two-way studies comparing glycoprofile of the originator and its given biosimilar are aplenty. However, the extent of analytical variation and similarity in glycoprofile across all approved versions of a drug is hardly explored. Using UHPLC and mass spectrometry, we compared the glycoprofiles of eight rituximab drug samples licensed for sale in India. While the types of glycans were found identical, the abundance of some glycans varied significantly within the tested population. The quality range of glycosylation parameters of the tested sample population differed significantly from the previously established values for US/EU licensed rituximab. As the mean abundance of the 90\% of identified glycans falls within {\textpm}3SD, the extent of mutual variations amongst tested lots is less significant compared to the extreme deviation from previously established QR limits. Thus, we propose this approach as an orthogonal method to capture glycan variations in licensed versions of mAbs for quality surveillance and in cases where originator samples{\textquoteright} are limiting. SIGNIFICANCE: As fluctuation in glycosylation may be of clinical significance, we identify that a one-to-one comparison with originator alone is insufficient in sensing the extent of variations in glycosylation parameters in licensed biosimilars of a given therapeutic mAb. Here we propose that future biosimilarity analysis may include an orthogonal approach of generating an additional combined QR range representing variations across the originator and its biosimilars. The glycosylation profiles of eight rituximab drug samples of different make obtained from the point of sale in India were found identical amongst the tested rituximab versions. However, the QR limits corresponding to important glycosylation parameters differed significantly across all tested samples from the previously established QR limits of US- and EU-licensed rituximab in statistical terms. Such an approach may be useful in defining the true range of glycan variations in licensed versions of therapeutic mAbs.

}, doi = {10.1016/j.jprot.2021.104267}, author = {Kaur, Tejinder and Shukla, Bhupendra Nath and Yadav, Vinay Kumar and Kulkarni, Mahesh J. and Rao, Alka} } @article {49810, title = {Characterization of S-homocysteinylation of Human Insulin and Its Implications in Diabetes}, journal = {Protein Journal}, volume = {44}, year = {2025}, month = {OCT}, pages = {598-610}, type = {Article}, abstract = {

Homocysteine thiolactone is a reactive thiol known for its interaction with various proteins. Nevertheless, there exists a paucity of information concerning the interaction between homocysteine thiolactone and human insulin, particularly regarding the mechanism by which homocysteine facilitates the reduction of disulfide bonds within insulin. In the present study, we have elucidated the binding sites of homocysteine to the cysteine residues (A6-B7 and A20-B19) that are implicated in the formation of intermolecular disulfide bonds in insulin through an in vitro reaction analyzed via LC-ESI MS/MS. This results in a reduction of disulfide bonds linking the A and B chains, which was corroborated by MALDI-TOF-MS and ESI-MS analysis. The secondary structure of insulin is affected by this modification, as evidenced by circular dichroism spectroscopy. In-silico studies also show that homocysteine affects the insulin structure. A glucose uptake assay conducted in Chinese hamster ovary (CHO) cells that stably express the insulin receptor revealed that HC-modified insulin is less effective in inducing glucose uptake compared to native insulin, suggesting that HC-induced structural modifications in insulin influence functional activity. This study provides insight into the HC-induced structural and functional changes in insulin and discusses the consequent implications for diabetes.

}, keywords = {Disulfide bonds, Homocysteinylation, insulin, Mass spectrometry}, issn = {1572-3887}, doi = {10.1007/s10930-025-10282-9}, author = {Sheikh, Amreen B. and Jathar, Swaraj M. and Tammara, Vaishnavi and Das, Atanu and Kulkarni, Mahesh J.} }