Analysis of the Structural Details of DsrO Protein from Allochromatium vinosum to Identify the Role of the Protein in the Redox Transport Process Through the dsr Operon

Sulfur oxidation is one of the oldest known redox processes in our environment mediated by phylogenetically diverse sets of microorganisms. The sulfur oxidation process is mediated mainly by dsr operon which is basically involved in the balancing and utilization of environmental sulfur compounds. DsrMKJOP complex from the dsr operon is the central player of this operon. DsrO is a periplasmic protein which binds FeS clusters responsible for electron transfer to DsrP protein from the dsr operon. DsrP protein is known to be involved in electron transfer to DsrM protein. DsrM protein would then donate the electrons to DsrK protein, the catalytic subunit of this complex. In the present work, we tried to analyze the role of DsrO protein of the dsr operon from the ecologically and industrially important organism Allochromatium vinosum. There are no previous reports that deal with the structural details of the DsrO protein. We predicted the structure of the DsrO protein obtained by homology modeling. The structure of the modeled protein was then docked with various sulfur anion ligands to understand the molecular mechanism of the transportation process of sulfur anion ligands by this DsrMKJOP complex. This study may therefore be considered as a first report of its kind that would therefore enlighten the pathway for analysis of the biochemical mechanism of sulfur oxidation reaction cycle by dsr operon.