Kinetics of thiosulfate oxidation, product and intermediate formation, and ³⁴S fractionation, were studied for the members of Alphaproteobacteria Paracoccus sp. SMMA5 and Mesorhizobium thiogangeticum SJT^T, the Betaproteobacteria member Pusillimonas ginsengisoli SBO3, and the Acidithiobacillia member Thermithiobacillus sp. SMMA2, during chemolithoautotrophic growth in minimal salts media supplemented with 20 mM thiosulfate. The two Alphaproteobacteria oxidized thiosulfate directly to sulfate, progressively enriching the end-product with ³⁴S; Δ³⁴S_{thiosulfate-sulfate} values recorded at the end of the two processes (when no thiosulfate was oxidized any further) were −2.9‰ and −3.5‰, respectively. Pusillimonas ginsengisoli SBO3 and Thermithiobacillus sp. SMMA2, on the other hand, oxidized thiosulfate to sulfate via tetrathionate intermediate formation, with progressive ³⁴S enrichment in the end-product sulfate throughout the incubation period; Δ³⁴S_{thiosulfate-sulfate}, at the end of the two processes (when no further oxidation took place), reached −3.5‰ and −3.8‰, respectively. Based on similar ³⁴S fractionation patterns recorded previously during thiosulfate oxidation by strains of Paracoccus pantotrophus, Advenella kashmirensis and Hydrogenovibrio crunogenus, it was concluded that progressive reverse fractionation, enriching the end-product sulfate with ³⁴S, could be a characteristic signature of bacterial thiosulfate oxidation.

中文翻译：

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34S 富集作为“Proteobacteria”中硫代硫酸盐氧化的特征

研究了Alphaproteobacteria Paracoccus sp.成员的硫代硫酸盐氧化、产物和中间体形成以及³⁴ S 分馏的动力学。SMMA5和慢生根瘤菌属thiogangeticum SJT ^Ť中，β-变形菌构件Pusillimonas ginsengisoli SBO3，并且Acidithiobacillia构件Thermithiobacillus藻。SMMA2，在补充有 20 mM 硫代硫酸盐的最小盐培养基中的化学自养生长过程中。两种Alphaproteobacteria 将硫代硫酸盐直接氧化为硫酸盐，最终产物逐渐富集³⁴ S；Δ ³⁴秒在两个过程结束时记录的_{硫代硫酸盐-硫酸盐}值（当没有硫代硫酸盐被进一步氧化时）分别为 -2.9‰ 和 -3.5‰。Pusillimonas ginsengisoli SBO3 和Thermithiobacillus sp。另一方面，SMMA2 通过连四硫酸盐中间体的形成将硫代硫酸盐氧化成硫酸盐，在整个培养期间，终产物硫酸盐中的³⁴ S逐渐富集；Δ ³⁴ S_{硫代硫酸盐-硫酸盐}在两个过程结束时（当没有进一步氧化发生时）分别达到-3.5‰和-3.8‰。基于先前在硫代硫酸盐氧化过程中记录的类似³⁴ S 分馏模式Paracoccus pantotrophus、Advenella kashmirensis和Hydrogenovibrio crunogenus，得出的结论是渐进式反向分馏，用³⁴ S富集终产物硫酸盐，可能是细菌硫代硫酸盐氧化的特征。