BIOENGINEERING OF THE CIRCULAR BACTERIOCIN FROM ENTEROCOCCUS FAECIUM NKR-5-3 BY NNK-SCANNING TO ENHANCE ITS BIOACTIVITY
BIOENGINEERING OF THE CIRCULAR BACTERIOCIN FROM ENTEROCOCCUS FAECIUM NKR-5-3 BY NNK-SCANNING TO ENHANCE ITS BIOACTIVITY
复制标题
DOI：
10.15414/jmbfs.4309
复制
发表时间：
2021-07
期刊：
影响因子：
--
通讯作者：
R. Perez;Riziel Hannah Aguimatang;T. Zendo;K. Sonomoto
中科院分区：
文献类型：
--
作者：
R. Perez;Riziel Hannah Aguimatang;T. Zendo;K. Sonomoto
细菌素是一种基因编码的抗菌肽，在食品工业中被视为安全的食品防腐剂，在制药工业中被视为传统抗生素的可能替代品。Enterocin NKR-5-3B是一种具有良好特征的圆形细菌素，由于其结构的圆形性质而具有优异的稳定性。本文通过nnk扫描构建了该细菌素的突变体文库，并以假定的关键残基为目标，希望获得具有增强生物活性的细菌素衍生物。13（13）个突变型表现出相对于天然细菌素的生物活性增强。表达V32C、V32A和L40G的表型生物活性增加最为显著，其相对生物活性分别为233、217和200%。由此产生的细菌素衍生物的硅分析显示，由于引入突变，细菌素衍生物的物理化学性质发生了显著变化，特别是其疏水性指数。V32C菌素衍生物的生物活性增强最强，其分子表面疏水性和等电点降低。这些变化可能促进了其生物活性的增强。这些关键突变的鉴定为今后合理设计具有增强生物活性的生物工程菌素的研究奠定了基础。
Bacteriocins are gene-encoded antimicrobial peptides that are traditionally appreciated as safe food preservative in the food industry and as possible alternative to conventional antibiotics in the pharmaceutical industry. Enterocin NKR-5-3B is a well characterized circular bacteriocin that possess exceptional stability due to the circular nature of its structure. In this paper, a mutant library of this bacteriocin was constructed through NNK-scanning whereby the presumed critical residues were targeted hoping to obtain bacteriocin derivatives with enhanced bioactivity. Thirteen (13) mutant phenotypes exhibited bioactivity enhancement relative to the native bacteriocin. The most notable bioactivity increases were observed from the phenotypes expressing V32C, V32A, and L40G that exhibited 233, 217, and 200% relative bioactivity, respectively. In-silico analyses of the resulting bacteriocin derivatives showed significant changes in the physico-chemical properties of the bacteriocin derivatives, particularly its hydrophobicity index, as a consequence of the introduced mutation. The V32C bacteriocin derivative which exhibited the strongest bioactivity enhancement was found to exhibit a reduction of the molecular surface hydrophobicity and isoelectric point. These changes may have contributed in the enhancement of its bioactivity. The identification of these critical mutations is highly valuable as basis for future studies on the rational design of bioengineered bacteriocins with enhanced bioactivity.