Interestingly, the re-consumption rate of S2O32- (Fig. 2, F), which is produced by SoxF metabolizing sulfide, was much slower than that of wild strain C. pinatubonensis JMP134 (Fig. 2, A), combined with the fact that continuously accumulated thiosulfate produced by SoxYZ, SoxB or SoxXA oxidized sulfide (Fig.S1), …show more content…
pinatubonensis JMP134 absorbs sulfate using assimilatory sulfate reduction. With the participation of ATP, sulfate adenylyltransferase (Reut_A1530, A1531, A2692 and A2693 in C. pinatubonensis JMP134) converts the sulfate to APS (adenosine-5'-phosphosulfate), and the resulting APS is phosphorylated by adenylylsulfate kinase (Reut_A0739 and A1530) to form PAPS (3ʹ-phosphoadenosyl 5ʹ-phosphosulfate). PAPS is reduced to sulfite by PAPS reductase (Reut_A2694), and then the sulfite reductase (Reut_A2696, B3940, B5161, and B5211) reduced sulfite to H2S. H2S is integrated into serine by cysteine synthase (Reut_A1804, A2337, A2560 and B4743) and eventually produces cysteine. In contrast, H2S can be produced as a by-product when cysteine is catalyzed by cysteine desulfurization enzyme CBS (genomic analysis does not find that C. pinatubonensis JMP134 contains any CBSs), CSE (Reut_A1355 and B3581) or MST (Reut_A0877 and A1183) (Paul and Snyder, …show more content…
As a sulfane sulfur receptor, sulfite and sulfane sulfur spontaneously react and generate thiosulfate (Kamyshny Jr et al., 2009; Xin et al., 2016). In contrast, as a sulfur donor, thiosulfate transfers the sulfane sulfur to other receptors (eg. Cyanide) by ST enzyme, while the thiosulfate is converted to sulfite (Xin et al., 2016). As described above, the sulfane sulfur consumed may also be derived from the metabolism of intracellular amino acids (Ida et al., 2014) or self-oxidation of H2S (Chen and Morris, 1972) or catalysis of enzymes (Xin et al.,