NUCLEOTIDE-SEQUENCE OF STREPTOCOCCUS-MUTANS SUPEROXIDE-DISMUTASE GENE AND ISOLATION OF INSERTION MUTANTS
NUCLEOTIDE-SEQUENCE OF STREPTOCOCCUS-MUTANS SUPEROXIDE-DISMUTASE GENE AND ISOLATION OF INSERTION MUTANTS
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DOI：
10.1128/jb.174.15.4928-4934.1992
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发表时间：
1992-08-01
影响因子：
3.2
通讯作者：
NAKAYAMA, K
中科院分区：
文献类型：
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作者：
NAKAYAMA, K
从大肠杆菌中克隆了一个编码超氧化物歧化酶（sod）的基因（sod），并测定了其核苷酸序列。推测其产物的氨基酸序列显示SOD基本为Mn型。sod基因的插入失活导致粗提取物中sod活性的丧失，表明该基因是变形链球菌中sod的唯一功能基因。此外，Southern blot分析表明，变形链球菌的染色体上没有额外的基因可以与SOD基序特异性的寡核苷酸探针杂交。缺乏sod的突变体能够在有氧条件下生长，尽管比亲本菌株生长得慢。
A gene (sod) encoding superoxide dismutase (SOD) was cloned from Streptococcus mutans in Escherichia coli, and its nucleotide sequence was determined. The presumptive amino acid sequence of its product revealed that the SOD is basically of Mn type. Insertional inactivation of the sod gene resulted in the loss of SOD activity in crude extracts, indicating that the gene represents the only functional gene for SOD in S. mutans. Moreover, Southern blot analysis indicated that the S. mutans chromosome had no additional gene which was hybridizable with an oligonucleotide probe specific for an SOD motif. The SOD-deficient mutants were able to grow aerobically, albeit more slowly than the parent strains.