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Biology subjects

Malakar, D.

Publications and source records attributed to Malakar, D..

3 recordsLinked to original sources

Recombinant binder of sperm protein1 (rec-BSP1) as a potent fertility factor mediates its effect on embryo production

ObjectiveTo understand the effect of recombinant BSP1 (rec-BSP1) on in vitro capacitation of sperm and fertilization study Method(s)Articles were screened for reports including rec-BSP1, Capacitation, in vitro fertilization InterventionNone Main Outcome Measure(s)Reproductive outcomes, effect on gametes and embryos Result(s)Here we report an optimization of condition for rec-BSP1 production which was used for in vitro capacitation and enhancement of buffalo embryo production. The sequence of the protein was used for multiple sequence alignment which has 99% similarity with PDC 109 protein. The expression of rec-BSP1 was carried out successfully with 1 mM IPTG at 160 C for 22 hrs and purified it in soluble form. The structure of rec-BSP1 was generated using 3D modelling and analysed its mode of binding with heparin and PC by molecular docking and the structural stability of rec-BSP1-PC and rec-BSP1-heparin complexes by using molecular dynamic (MD) simulation. The effect of rec-BSP1 was observed on in vitro capacitation of spermatozoa and buffalo blastocyst production. It was found that the rec-BSP1 enhanced the sperm motility at a concentration of 50 g/ml for 1 h of incubation without having any detrimental effect on the sperm morphology and a significant increase in blastocyst production at concentration of 50 g/ml rec-BSP1. Hence this finding represents a new insight and advance the prospective approach to develop a potential fertility factor in reproduction. Conclusion(s)The purified rec-BSP1 may enhance on male fertility and mediated its effect on in vitro blastocyst production in buffalo.

bioengineering

A high content lipidomics method using scheduled MRM with variable retention time window and relative dwell time weightage

Lipid compositions of cells, tissues and bio-fluids are complex, with varying concentrations and structural diversity, which makes their identification challenging. Newer methods for comprehensive analysis of lipids are thus necessary. Herein, we propose a targeted-mass spectrometry based method for large-scale lipidomics using a combination of variable retention time window and relative dwell time weightage. Using this, we detected more than 1000 lipid species, including structural isomers. The limit of detection varied from femtomolar to nanomolar range and the coefficient of variance <30% for 849 lipid species. We used this method to identify lipids altered due to Vitamin B12 deficiency and found that the levels of lipids with {omega}-3 fatty acid chains decreased while those with {omega}-6 increased. This method enables identification of by far the largest number of lipid species with structural isomers in a single experiment and would significantly advance our understanding of the role of lipids in biological processes.

biochemistry

Phenotypic and molecular characterization of extended spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae isolates from various samples of animal origin from Assam, India

Extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae has become a major threat globally. Here we have characterized ESBL producing E. coli and K. pneumoniae from various sources, studied antibiogram and resistance gene profiles. Out of 385 samples, 31 (8.05%) were positive for ESBL producing E. coli. Such isolates could be recovered from 10.05, 8.33, 15.63, 6.67 and 4.35 per cent of cattle milk, curd, chicken, pork and cattle faeces samples, respectively. A total of 59 (15.32%) samples were positive for ESBL producing K. pneumoniae, which were isolated from 14.35, 6.25, 21.43 and 34.78 per cent cattle milk, chicken, beef and cattle faeces, respectively. All the 90 isolates were confirmed as ESBL producers by CDT and ESBL-E strip tests. Antibiogram revealed that 74.19% and 69.49% of the ESBL producing E. coli and K. pneumoniae isolates, respectively showed resistance to ceftizoxime, 25.81% and 23.73% to both co-trimoxazole and tetracycline, 19.35% and 25.42% to ciprofloxacin, 9.68% and 16.95% to chloramphenicol, 3.23% and 5.08% to pipercillin-tazobactam, and 3.23% and 3.39% to gentamicin. Resistance gene profiling showed blaCTX-M gene as most predominant (100%). The blaTEM gene was found in 54.84% and 55.93%, blaSHV gene in 90.32% and 77.97%, Sul 1 gene in 90.32% and 86.44% of ESBL producing E. coli and K. pneumoniae isolates, respectively. The Int1 gene was detected in 70.97% and 62.71% isolates, while qnrB gene was found in 3.23% and 10.17% of E. coli and K. pneumoniae isolates, respectively.

molecular biology