Sulfate-reducing pathway in Escherichia coli involving bound intermediates
Sulfate-reducing pathway in Escherichia coli involving bound intermediates
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大肠杆菌中涉及结合中间体的硫酸盐还原途径
DOI：
10.1128/jb.125.3.923-933.1976
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发表时间：
1976
影响因子：
3.2
通讯作者：
J. Schiff
中科院分区：
文献类型：
--
作者：
M. Tsang;J. Schiff
虽然硫酸盐还原途径在大肠杆菌涉及游离亚硫酸盐和硫化物已被提出，它表明，在小球藻，一个途径，涉及绑定中间体也存在。E.大肠杆菌提取物含有磺基转移酶，其将磺酰基从核苷磷酸硫酸盐转移到受体以形成有机硫代硫酸盐。该酶特异于腺苷3 '-磷酸5'-磷酸硫酸盐，不利用腺嘌呤5 '-磷酸硫酸盐，并转移到分子量和氨基酸组成与硫氧还蛋白相同的载体分子上。在没有硫氧还蛋白的情况下，仅观察到非常低水平的磺基向硫醇的转移。与小球藻一样，可以检测到将谷胱甘肽-S-SO 3-还原为结合硫化物的硫代磺酸盐还原酶活性。在大肠在大肠杆菌中，该酶使用还原的烟酰胺腺嘌呤二核苷酸磷酸和Mg 2+，但不需要添加铁氧还蛋白或铁氧还蛋白烟酰胺腺嘌呤二核苷酸磷酸还原酶。虽然在小球藻中硫代磺酸盐还原酶似乎是一种不同于亚硫酸盐还原酶的酶，但E。大肠杆菌硫代磺酸盐还原酶和亚硫酸盐还原酶的活性可能相同。
Although a sulfate-reducing pathway in Escherichia coli involving free sulfite and sulfide has been suggested, it is shown that, as in Chlorella, a pathway involving bound intermediates is also present. E. coli extracts contained a sulfotransferase that transferred the sulfonyl group from a nucleosidephosphosulfate to an acceptor to form an organic thiosulfate. This enzyme was specific for adenosine 3'-phosphate 5'-phosphosulfate, did not utilize adenine 5'-phosphosulfate, and transferred to a carrier molecule that was identical with thioredoxin in molecular weight and amino acid composition. In the absence of thioredoxin, only very low levels of the transfer of the sulfo group to thiols was observed. As in Chlorella, thiosulfonate reductase activity that reduced glutathione-S-SO3- to bound sulfide could be detected. In E. coli, this enzyme used reduced nicotinamide adenine dinucleotide phosphate and Mg2+, but did not require the addition of ferredoxin or ferredoxin nicotinamide adenine dinucleotide phosphate reductase. Although in Chlorella the thiosulfonate reductase appears to be a different enzyme from the sulfite reductase, the E. coli thiosulfonate reductase and sulfite reductase may be activities of the same enzyme.