COMPARATIVE SEQUENCE AND STRUCTURAL CONFORMATION ANALYSIS OF RECA PROTEIN

Water molecules are very important for stabilizing the protein structures. The influence of hydration (or) dehydration on protein structures leads to the changes in the activity of proteins as well their conformation. In our present study, we madde an attempt to understand the various RecA protein sequence similarity with respect to E. coli RecA Protein and comparative structure and functional conformation studies between MsRecA protein (dehydrated state) and EcRecA + DNA bound structures (active state) as well ATP-complexed DrRecA protein structure. From the sequence similarity studies, it was identified that the E.coli RecA protein exhibits the highest sequence similarity (100%) with the Shigella dysenteriae serotype 1 (strain Sd197), Shigella flexneri and the lowest sequence similarity (46%) with the Mycoplasma genitalium. From the structural alignment & superposition studies, it can be inferred that the low hydrated MsRecA protein conformation is very closely similar to the active conformation of the EcRecA protein. This confers that the lower less water molecules favors the active conformational state of the RecA protein in both M. smegmatis & E. coli whereas the ATP-bound complex of RecA protein of D. radiodurans is exhibiting different conformation from the active state conformation.