Screening and Toxicity Analysis of Catechin Isomers Against FemA Protein.

Fem proteins are the essential structural proteins of various gram-positive bacteria. These are of three different types namely FemX (FmhB), FemA and FemB. Only two Fem protein crystallographic structures are available till date, one for FemA in Staphylococcus aureus and another for FemX in Weissella viridescensis. In this study, computational methods are used to evaluate interaction of FemA protein with catechin and epicatechin analogues. The interaction of FemA protein with catechin and epicatechin analogues are confirmed by binding energy and scores given by Autodock Vina and UCSF Dock docking softwares, which is followed by Lipinski filters and toxicity studies using online Lipinski server of SCFBIO and OSIRIS. Catechin gallate has been found as the best ligand for FemA protein in all aspects and it has outperformed all catechin and epicatechin isomers.