Hussein Walaa E, Huang En, Ozturk Ismet, Somogyi Árpád, Yang Xu, Liu Baosheng, Yousef Ahmed E
Department of Food Science and Technology, The Ohio State University, Columbus, OH, United States.
Department of Microbiology and Immunology, National Research Center, Giza, Egypt.
Front Microbiol. 2020 Jul 14;11:1381. doi: 10.3389/fmicb.2020.01381. eCollection 2020.
The quest for potent alternatives to the currently used antimicrobials is urged by health professionals, considering the rapid rise in resistance to preservatives and antibiotics among pathogens. The current study was initiated to search for novel and effective bacteriocins from food microbes, preferably lactic acid bacteria (LAB), for potential use as preservatives. Advances in genome-guided mass spectrometry (MS) were implemented to expedite identifying and elucidating the structure of the recovered antimicrobial agent. A LAB strain, OSY-TC318, was isolated from a Turkish cheese, and the crude extract of the cultured strain inhibited the growth of various pathogenic and spoilage bacteria such as , , , , ser. Typhimurium, and . The antimicrobial producer was identified as using MS biotyping and genomic analysis. Additionally, OSY-TC318 was distinguished from closely related strains using comparative genomic analysis. Based on analysis, the genome of the new strain contained a complete lantibiotic biosynthetic gene cluster, encoding a novel lantibiotic that was designated as paraplantaricin TC318. The bioinformatic analysis of the gene cluster led to the prediction of the biosynthetic pathway, amino acid sequence, and theoretical molecular mass of paraplantaricin TC318. To verify the genomic analysis predictions, paraplantaricin TC318 was purified from the producer cellular crude extract using liquid chromatography, followed by structural elucidation using Fourier transform ion cyclotron resonance MS analysis. This genome-guided MS analysis revealed that the molecular mass of paraplantaricin TC318 is 2,263.900 Da, its chemical formula is CHNOS, and its primary sequence is F-K-S-W-S-L-C-T-F-G-C-G-H-T-G-S-F-N-S-F-C-C. This lantibiotic, which differs from mutacin 1140 at positions 9, 12, 13, and 20, is considered a new member of the epidermin group in class I lantibiotics. In conclusion, the study revealed a new strain producing a novel lantibiotic that is potentially useful in food and medical applications.
鉴于病原体对防腐剂和抗生素的耐药性迅速上升，健康专业人士迫切要求寻找目前使用的抗菌剂的有效替代品。当前的研究旨在从食品微生物，最好是乳酸菌（LAB）中寻找新型且有效的细菌素，以潜在用作防腐剂。实施了基因组引导的质谱（MS）技术进展，以加快对回收的抗菌剂的鉴定和结构阐明。从一种土耳其奶酪中分离出一株LAB菌株OSY-TC318，该培养菌株的粗提物抑制了各种致病和腐败细菌的生长，如 、 、 、 、鼠伤寒沙门氏菌血清型和 。使用MS生物分型和基因组分析将抗菌剂产生菌鉴定为 。此外，通过比较基因组分析将OSY-TC318与密切相关的菌株区分开来。基于 分析，新菌株的基因组包含一个完整的羊毛硫抗生素生物合成基因簇，编码一种新型羊毛硫抗生素，命名为副植物乳杆菌素TC318。对该基因簇的生物信息学分析导致了副植物乳杆菌素TC318的生物合成途径、氨基酸序列和理论分子量的预测。为了验证基因组分析预测，使用液相色谱从产生菌细胞粗提物中纯化副植物乳杆菌素TC318，随后使用傅里叶变换离子回旋共振MS分析进行结构阐明。这种基因组引导的MS分析表明，副植物乳杆菌素TC318的分子量为2,263.900 Da，其化学式为CHNOS，其一级序列为F-K-S-W-S-L-C-T-F-G-C-G-H-T-G-S-F-N-S-F-C-C。这种羊毛硫抗生素在第9、12、13和20位与变链菌素1140不同，被认为是I类羊毛硫抗生素中表皮菌素组的一个新成员。总之，该研究揭示了一种产生新型羊毛硫抗生素的新 菌株，该抗生素在食品和医疗应用中可能有用。
