Embedded Files
Small RNA-mediated regulation in bacteria
Small RNA-mediated regulation in bacteria
Our lab aims to understand how small noncoding RNAs control gene expression in bacteria. The discovery and characterization of small regulatory RNAs (sRNAs) in bacteria has exploded in recent years. These sRNAs act either by modulating protein activity or by base pairing with target mRNAs with which they share limited or extended complementarity. Mechanistic insights into how sRNAs bind mRNAs and proteins, how they compete with each other and how they function to regulate different physiological processes are active areas of our research. Ribonucleases also play an essential regulatory role for the expression of these sRNAs. Three different model bacteria were utilized - Escherichia coli, Mycobacterium sp. and Deinococcus radiodurans.
Two sRNAs, SdsR/RyeB and RyeA/SraC, the cognate genes of which are located in the intergenic region of pphA and yebY genes in opposite polarities, have recently been found to act as toxin/antitoxin system in E. coli. RyeA is a ~270 nt long sRNA, an internal segment of which is completely complementary to 104 nt long RyeB. RyeB is not detectable in the exponential phase, but has been reported to be abundant upon entry into the stationary phase. Thus, its expression is regulated by the stationary phase Sigma-factor RpoS at the transcriptional level. Ectopic expression of RyeB in the exponential phase resulted in cell filamentation and cell death. Overexpression of RyeA alleviates RyeB-driven cell death, which indicates its antagonistic role to RyeB function.
Sustainable engineering by exploiting a novel bacterial laccase
Sustainable engineering by exploiting a novel bacterial laccase
Effluents from dyeing industries are toxic to animals and plants since many dyes are synthesized from familiar carcinogenic compounds. Textile industry is the leading among all dyeing industries in discharging synthetic, recalcitrant, and reactive dyestuffs, and various health-hazardous bleaching chemicals like sodium hypochlorite, potassium permanganate etc. to the waste water, which are highly detrimental to environmental ecosystem. Dye degradation and decolourization by microorganisms or their enzymes have emerged as a better eco-friendly sustainable process over other physicochemical methods. In the current study, we isolated a high molecular weight (88 kDa) extremophilic laccase (LacT) from Brevibacillus agri, with the aim to exploit its extreme characters in denim bleaching and dye decolourization at industrial conditions and to minimize the release of pernicious chemicals into the environment. Characterization of LacT revealed that it was associated with thermophilic, acidophilic character with high salt, organic solvent and divalent metal tolerance properties. It showed specificity towards wide range of substrates. Denim bleaching efficiency of LacT was optimum at pH 4.0 and it appeared to be surpassing over other reported laccases. LacT also exhibited remarkable efficacy in the decolourization of water-soluble health hazardous azo-dyes, and thus, transpired to be promising bio-bleaching and dye decolourizing agent.
Page updated
Google Sites
Report abuse