Structural and Biophysical properties of therapeutically important proteins Rv1509 and Rv2231A of Mycobacterium tuberculosis.

Through comparative analyses using BLASTp and BLASTn of the 25 target sequences, our research identified two unique post-transcriptional modifiers, Rv1509 and Rv2231A, which serve as distinctive and characteristic proteins of M.tb - the Signature Proteins. Here, we have characterized these two signature proteins associated with pathophysiology of M.

Human TMPRSS2 non-catalytic ectodomain and SARS-CoV-2 S2' subunit interaction mediated SARS-CoV-2 endocytosis: a model proposal with virtual screening for potential drug molecules to inhibit this interaction.

This study proposes a novel model for integration of SARS-CoV-2 into host cell via endocytosis as a possible alternative to the prevailing direct fusion model. It is known that the SARS-CoV-2 spike protein undergoes proteolytic cleavage at S1-S2 cleavage site and the cleaved S2 domain is primed by the activated serine protease domain (SPD) of humanTMPRSS2 to become S2'. The activated SPD of TMPRSS2 is formed after it is cleaved by autocatalysis from the membrane bound non-catalytic ectodomain (hNECD) comprising of LDLRA CLASS-I repeat and a SRCR domain.

Organophosphate hydrolase interacts with ferric-enterobactin and promotes iron uptake in association with TonB-dependent transport system.

Our previous studies have shown the existence of organophosphate hydrolase (OPH) as a part of the inner membrane associated Ton complex (ExbB/ExbD and TonB) of Sphingobium fuliginis. We now show its involvement in iron uptake by establishing direct interactions with ferric-enterobactin. The interactions between OPH and ferric-enterobactin were not affected even when the active site architecture is altered by substituting active site aspartate with either alanine or asparagine.

Organophosphate hydrolase interacts with Ton components and is targeted to the membrane only in the presence of the ExbB/ExbD complex.

Our study aims to investigate the physiological role of organophosphate hydrolase (OPH), hitherto known for its involvement in the degradation of organophosphate insecticides and nerve agents in Sphingobium fuliginis. We find that OPH exists as part of the TonB-dependent Transport system that is involved in nutrient transport across the bacterial outer membrane. OPH interacts physically with the Ton complex components ExbD and TonB.