Chemolithoautotrophic oxidation of thiosulfate, tetrathionate and thiocyanate by a novel rhizobacterium belonging to the genus Paracoccus.
Two tropical leguminous-rhizospheric strains, SST and JT 001, phylogenetically closest to Paracoccus thiocyanatus and Paracoccus pantotrophus, respectively, were isolated on reduced sulfur compounds as sole energy and electron sources. While SST had versatile chemolithotrophic abilities to oxidize thiosulfate, tetrathionate, thiocyanate, sulfide and elemental sulfur, JT 001 could oxidize thiosulfate, soluble sulfide, elemental sulfur and a relatively lesser amount of tetrathionate. Positive hybridization signals were detected for JT 001 but not SST, when their genomic DNAs were probed with DIG-labeled sulfur oxidation genes amplified from the chemolithotrophic alphaproteobacterium Pseudaminobacter salicylatoxidans KCT001. Though the new isolate SST exhibited high 16S rRNA gene sequence similarity with the monotypic species P. thiocyanatus, it was found to be considerably distinct from the latter in terms of phenotypic and chemotaxonomic characteristics. Polyphasic systematic analysis, however, confirmed that JT 001 was a strain of P. pantotrophus.
Ghosh
Wriddhiman
W
Department of Microbiology, Bose Institute, Kolkata, India. wriman@rediffmail.com
Roy
Pradosh
P
D052818:Autotrophic Processes; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D010230:Paracoccus / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013776:Tetrathionic Acid / Q000378:metabolism*; D013885:Thiosulfates / Q000378:metabolism*; D013997:Time Factors
D012336:RNA, Ribosomal, 16S; D013885:Thiosulfates; D013776:Tetrathionic Acid; D010100:Oxygen