No abstract

No abstract

mesT demonstrated esterase as well as epoxide hydrolase activity. It was membrane bound and was upregulated under hypoxic conditions. The enzyme was able to degrade styrene oxide. The presence of antisense against this gene resulted in the inhibition of in vitro bacterial growth/survival in the presence of styrene oxide. Conclusion & future perspective: We demonstrated that mesT possessed epoxide hydrolase activity and styrene oxide might be its physiological substrate. Inhibition of mesT reduced the growth of the bacteria in presence of styrene oxide and its expression under hypoxic condition suggested its role in intracellular survival of bacteria.

C-Phycocyanin (C-PC) is a natural blue colored protein of Spirulina platensis. Several methods based on chemical, physical, and enzymatic processes have been reported for the extraction of C-PC. However, most of the processes are either costly and/or time-consuming and/or produce C-PC with less purity. In view of this, a very simple and effective method was developed to extract C-PC with high purity and without involving any energy-consuming process from S. platensis. Wet biomass of S. platensis was harvested and incubated in an optimized 2-(N-morpholino)­ethanesulfonic acid buffer with no supplement of any other compounds under dark, anaerobic, and still conditions. These conditions facilitated the leaching out of C-PC from the cells. The purity ratio of the blue color C-PC supernatant obtained was enhanced by precipitation and dialysis. The purity ratio of C-PC produced was 0.644 and increased to 1.345 upon simple dialysis of the crude C-PC. The purity of C-PC was 6.17 upon purifying through column chromatography. Hence, a simple process was developed for producing C-PC of much higher purity than therapeutic grade (>4). Furthermore, the molecular regulation of the extracellular release of C-PC from S. platensis cells was monitored through relative expression levels of α and β subunits of C-PC genes during specific buffer vis-à-vis water as a control. Expression levels of genes encoding α and β subunits of C-PC were found to be upregulated in the case of the 2-(N-morpholino)­ethanesulfonic acid buffer treated algal cells compared to water treated algal cells. The higher level expression of these genes documented the higher and specific production of C-PC by the S. platensis upon 2-(N-morpholino)­ethanesulfonic acid buffer treatment.

mbtJ, an acetyl-hydrolase/esterase, enhanced the survival of M. tuberculosis under iron stress, affected the growth/infection efficiency in M. smegmatis, suggesting its pivotal role in the intracellular survival of bacterium.