Exploring the role of SoxA and SoxX in sulphur oxidation in Allochromatium vinosum through Protein - protein docking : An in silico approach

Thiosulphate (S2O32-) is a stable and environmentally abundant sulphur compound of intermediate oxidation state and fulfils an important role in the natural sulphur cycle. There are main two types of thiosulfate-oxidizing Sox enzyme system type one group 1 forms sulfur globules as intermediates Allochromatium vinosum (A.vino or A.vinosum)), group 2 which does not form sulphur globules as intermediate form for example Paracoccus pantotrophus . Sox genes in A. vinosum, are separated into three gene clusters. Cluster one comprises Alvin_2108 to Alvin_2112.The second gene cluster extends between Alvin_2165 and Alvin_2167 .The third gene cluster includes Alvin_2168 to Alvin_2182.Where SoxX, SoxA, are encoded by Alvin_2168 to Alvin_2169. In the present work, homology modeling has been used to build the three dimensional structures of SoxA, and SoxX. With the help of protein -protein docking and Protein Interaction Calculator (PIC) sever the amino acid residues of these proteins involved in the interactions have been identified. The interactions between the SoxA, and SoxX proteins are mediated mainly through hydrogen bonding, hydrophobic interaction, electrostatic interaction. Possible mechanisms of interaction between the SoxA, and SoxX have identified in spite the absence of SoxK.