Department of Fermentation Technology, Faculty of Engineering, Hiroshima University, Saijo-Cho, Higashi-Hiroshima, 724, Japan.
Appl Environ Microbiol. 1986 Oct;52(4):617-22. doi: 10.1128/aem.52.4.617-622.1986.
Methanosarcina barkeri Fusaro (DSM 804) could grow on methanol in a mineral medium containing cysteine or thiosulfate as the sole sulfur source. Optimum growth occurred at cysteine concentrations of 1 to 2.8 mM and at thiosulfate concentrations of 2.5 to 5 mM. No inhibition of growth was observed even when these concentrations were doubled in the culture medium. Under the optimum cysteine and thiosulfate concentrations, the generation times of the organism were about 8 to 10 and 10 to 12 h, respectively, giving a cell yield of about 0.14 to 0.17 and 0.08 to 0.11 g (dry weight)/g of methanol consumed. The organism metabolized cysteine and thiosulfate during growth, giving rise to sulfide in the culture medium. H(2)S evolution from cysteine and thiosulfate was catalyzed by two enzymes, namely cysteine desulfhydrase and thiosulfate reductase, respectively, as revealed by enzyme assay in the crude cell-free extract of the organism.
巴氏甲烷八叠球菌 Fusaro（DSM 804）可以在含有半胱氨酸或硫代硫酸盐作为唯一硫源的矿物培养基上利用甲醇生长。最佳生长发生在半胱氨酸浓度为 1 至 2.8 mM 和硫代硫酸盐浓度为 2.5 至 5 mM 时。即使在培养基中这些浓度加倍，也没有观察到生长受到抑制。在最佳半胱氨酸和硫代硫酸盐浓度下，该生物的代时约为 8 至 10 小时和 10 至 12 小时，分别产生约 0.14 至 0.17 和 0.08 至 0.11 g（干重）/消耗的甲醇 g。该生物在生长过程中代谢半胱氨酸和硫代硫酸盐，导致培养基中的硫化物。通过对该生物的粗无细胞提取物中的酶进行酶测定，揭示了 H2S 分别由两种酶（半胱氨酸脱巯基酶和硫代硫酸盐还原酶）催化从半胱氨酸和硫代硫酸盐中释放。
