School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
Key Laboratory of Sustainable Development of Marine Fisheries, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, China.
Antonie Van Leeuwenhoek. 2024 May 29;117(1):84. doi: 10.1007/s10482-024-01974-w.
Pseudoalteromonas piscicida 2515, isolated from Litopenaeus vannamei culture water, is a potential marine probiotic with broad anti-Vibrio properties. However, genomic information on P. piscicida 2515 is scarce. In this study, the general genomic characteristics and probiotic properties of the P. piscicida 2515 strain were analysed. In addition, we determined the antibacterial mechanism of this bacterial strain by scanning electron microscopy (SEM). The results indicated that the whole-genome sequence of P. piscicida 2515 contained one chromosome and one plasmid, including a total length of 5,541,406 bp with a G + C content of 43.24%, and 4679 protein-coding genes were predicted. Various adhesion-related genes, amino acid and vitamin metabolism and biosynthesis genes, and stress-responsive genes were found with genome mining tools. The presence of genes encoding chitin, bromocyclic peptides, lantibiotics, and sactipeptides showed the strong antibacterial activity of the P. piscicida 2515 strain. Moreover, in coculture with Vibrio anguillarum, P. piscicida 2515 displayed vesicle/pilus-like structures located on its surface that possibly participated in its bactericidal activity, representing an antibacterial mechanism. Additionally, 16 haemolytic genes and 3 antibiotic resistance genes, including tetracycline, fluoroquinolone, and carbapenem were annotated, but virulence genes encoding enterotoxin FM (entFM), cereulide (ces), and cytotoxin K were not detected. Further tests should be conducted to confirm the safety characteristics of P. piscicida 2515, including long-term toxicology tests, ecotoxicological assessment, and antibiotic resistance transfer risk assessment. Our results here revealed a new understanding of the probiotic properties and antibacterial mechanism of P. piscicida 2515, in addition to theoretical information for its application in aquaculture.
从凡纳滨对虾养殖水中分离到的假性交替单胞菌 2515 是一种具有广谱抗弧菌特性的潜在海洋益生菌。然而，关于 2515 菌株的基因组信息还很缺乏。在本研究中，我们分析了 2515 菌株的一般基因组特征和益生菌特性。此外，我们通过扫描电子显微镜（SEM）确定了该细菌菌株的抗菌机制。结果表明，2515 株的全基因组序列包含一个染色体和一个质粒，总长度为 5541406bp，G+C 含量为 43.24%，预测有 4679 个蛋白质编码基因。通过基因组挖掘工具发现了各种粘附相关基因、氨基酸和维生素代谢与生物合成基因以及应激响应基因。编码几丁质、溴环肽、杆菌肽和沙肽的基因的存在表明 2515 菌株具有很强的抗菌活性。此外，在与鳗弧菌共培养时，2515 株表面出现囊泡/菌毛样结构，可能参与其杀菌活性，代表一种抗菌机制。此外，还注释了 16 个溶血基因和 3 个抗生素抗性基因，包括四环素、氟喹诺酮和碳青霉烯，但未检测到编码肠毒素 FM（entFM）、环七肽（cereulide）和细胞毒素 K 的毒力基因。应进一步进行测试以确认 2515 株的安全性特征，包括长期毒性测试、生态毒性评估和抗生素抗性转移风险评估。我们的研究结果揭示了 2515 株的益生菌特性和抗菌机制的新认识，为其在水产养殖中的应用提供了理论信息。
