Characterization of bacteriocin related genes discovered in a novel probiotic isolate Enterococcus faecium W1
Characterization of bacteriocin related genes discovered in a novel probiotic isolate Enterococcus faecium W1
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在新型益生菌分离株屎肠球菌 W1 中发现的细菌素相关基因的特征
DOI：
10.1099/acmi.ac2020.po0370
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发表时间：
2020
影响因子：
--
通讯作者：
Aziz F
中科院分区：
文献类型：
--
作者：
Aziz F
目的：分离并表征新型肠球菌分离株屎肠球菌 W1 的基因组分析鉴定的细菌素活性。方法和结果：新型肠球菌的培养物发酵。 faeciumisolate，W1 对单核细胞生成李斯特菌和多种其他革兰氏阳性和革兰氏阴性细菌表现出高水平的抗菌活性。发酵物的硫酸铵沉淀，随后进行疏水相互作用层析，显示出与仅含有低分子量蛋白质的级分相关的杀菌活性。通过细胞毒性测定（MTT）和细胞凋亡诱导测量，相同的级分对人类癌细胞系 HT-29 具有活性。 E.全基因组测序faeciumW1揭示了五个细菌素相关基因簇，缺乏毒力因子和抗生素抗性基因。为了确认抗菌活性与所鉴定的细菌素基因相关，选择的细菌素基因被克隆并在大肠杆菌中表达为His标签蛋白。大肠杆菌。针对单核细胞增生利斯特氏菌的杀菌活性与通过金属亲和层析纯化的蛋白质相关。正在进行结构功能分析以研究关键残基在活性中的作用。结论：E。 faeciumW1 是用作益生菌补充剂或食品保存的有前途的候选者。细菌素相关基因具有功能性，可以进行改进，以供将来用作抗菌剂和癌细胞治疗剂。该研究的意义和影响：需要新的方法来解决日益严重的抗生素耐药性问题。在大肠杆菌中鉴定出细菌素的表达。 faeciumW1 除了用作益生菌之外，还可以为这一努力做出贡献。
Aims:To isolate and characterize the bacteriocin activity identified by the genomic analysis of a novel enterococcal isolate,Enterococcus faeciumW1Methods and Results:Culture fermentates of a novelE. faeciumisolate, W1 showed high levels of antimicrobial activity against Listeria monocytogenesisand a variety of other Gram+ve and Gram-ve bacteria. Ammonium sulphate precipitation of the fermentates followed by hydrophobic interaction chromatography showed bactericidal activity correlated with fractions containing only low molecular weight proteins. The same fractions had activity on human cancer cell line HT-29 measured by cytotoxicity assay (MTT) and apoptosis induction. Whole-genome sequencing ofE. faeciumW1 revealed five bacteriocin related gene clusters, a lack of virulence factors and lack of antibiotic resistance genes. To confirm that antimicrobial activity was correlated with the bacteriocin genes identified, selected bacteriocin genes were cloned and expressed as His-tagged proteins inE. coli. Bactericidal activity against L. monocytogenes was associated with protein purified by metal affinity chromatography. A structure-function analysis to investigate the role of key residues in activity is ongoing.Conclusion:E. faeciumW1 is a promising candidate for use as a probiotic supplement or in food preservation. The bacteriocin related genes are functional and could be improved for future use as antimicrobial and cancer cell therapeutics. Significance and Impact of the Study: There is a need for new approaches to the growing problem of antibiotic resistance. Expression of bacteriocins identified inE. faeciumW1 could contribute to this endeavour in addition to its use as a probiotic organism.