Enterocin F4-9, a Novel O-Linked Glycosylated Bacteriocin
Enterocin F4-9, a Novel O-Linked Glycosylated Bacteriocin
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DOI：
10.1128/aem.00940-15
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发表时间：
2015-07-01
影响因子：
4.4
通讯作者：
Sonomoto, Kenji
中科院分区：
文献类型：
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作者：
Maky, Mohamed Abdelfattah;Ishibashi, Naoki;Sonomoto, Kenji
从埃及盐发酵鱼中分离的粪肠球菌F4-9产生一种新的细菌素，称为肠菌素F4-9。肠菌素F4-9经三步纯化，质谱测定其分子量为5，516.6 Da。氨基酸和DNA序列分析表明，前肽由67个氨基酸残基组成，前导肽含有双甘氨酸切割位点，产生47个氨基酸的成熟肽。Enterocin F4-9由两个分子的N-乙酰葡糖胺β-O-连接到Ser 37和Thr 46修饰。O-连接的N-乙酰葡糖胺部分对于肠菌素F4-9的抗微生物活性是必需的。肠菌素F4-9基因簇的进一步分析鉴定了enfC，其与糖基转移酶具有高序列相似性。肠菌素F4-9的抗微生物活性覆盖有限范围的细菌，有趣的是，包括革兰氏阴性菌株，大肠杆菌JM 109。Enterocin F4-9对蛋白酶敏感，在宽pH范围内具有活性，并且对热具有中等抗性。
Enterococcus faecalis F4-9 isolated from Egyptian salted-fermented fish produces a novel bacteriocin, termed enterocin F4-9. Enterocin F4-9 was purified from the culture supernatant by three steps, and its molecular mass was determined to be 5,516.6 Da by mass spectrometry. Amino acid and DNA sequencing showed that the propeptide consists of 67 amino acid residues, with a leader peptide containing a double glycine cleavage site to produce a 47-amino-acid mature peptide. Enterocin F4-9 is modified by two molecules of N-acetylglucosamine beta-O-linked to Ser37 and Thr46. The O-linked N-acetylglucosamine moieties are essential for the antimicrobial activity of enterocin F4-9. Further analysis of the enterocin F4-9 gene cluster identified enfC, which has high sequence similarity to a glycosyltransferase. The antimicrobial activity of enterocin F4-9 covered a limited range of bacteria, including, interestingly, a Gram-negative strain, Escherichia coli JM109. Enterocin F4-9 is sensitive to protease, active at a wide pH range, and moderately resistant to heat.