Structural insight into the mode of interactions of SoxL from Allochromatium vinosum in the global sulfur oxidation cycle.
Microbial redox reactions of inorganic sulfur compounds are one of the important reactions for the recycling of sulfur to maintain the environmental sulfur balance. These reactions are carried out by phylogenetically diverse microorganisms. The sulfur oxidizing gene cluster (sox) of α-proteobacteria, Allochromatium vinosum comprises two divergently transcribed units. The central players of this process are SoxY, SoxZ and SoxL. SoxY is sulfur compound binder which binds to sulfur anions with the help of SoxZ. SoxL is a rhodanese like protein, which then cleaves off the sulfur substrate from the SoxYZ complex to recycle the SoxY and SoxZ. In the present work, homology modeling has been employed to build the three dimensional structures of SoxY, SoxZ and SoxL. With the help of docking simulations the amino acid residues of these proteins involved in the interactions have been identified. The interactions between the SoxY, SoxZ and SoxL proteins are mediated mainly through hydrogen bonding. Strong positive fields created by the SoxZ and SoxL proteins are found to be responsible for the binding and removal of the sulfur anion. The probable biochemical mechanism of sulfur anion oxidation process has been identified.
Department of Biochemistry and Biophysics, University of Kalyani, Nadia, Kalyani 741235, India. angshuman_bagchi@yahoo.com
Angshuman
A
Bagchi
D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D020134:Catalytic Domain; D002841:Chromatiaceae / Q000201:enzymology* / Q000235:genetics; D006860:Hydrogen Bonding; D062105:Molecular Docking Simulation; D005810:Multigene Family; D010084:Oxidation-Reduction; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000737:chemistry / Q000235:genetics; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D017433:Protein Structure, Secondary; D040681:Structural Homology, Protein; D013455:Sulfur / Q000737:chemistry*; D013884:Thiosulfate Sulfurtransferase / Q000737:chemistry* / Q000235:genetics
D001426:Bacterial Proteins; D013455:Sulfur; D050862:Oxidoreductases Acting on Sulfur Group Donors; D013884:Thiosulfate Sulfurtransferase