Screening of Antagonistic Bacteria against Three Aquatic Pathogens and Characterization of Lipopeptides in Bacillus cereus BA09

• Published in: Journal of microbiology and biotechnology Vol. 34; no. 10; pp. 2023 - 2032
• Main Authors: Xinran Shi, Weijia Zhou, Xiaocen Lu, Cuiyan Cao, Dong Sheng, Xu Ren, Nanlin Jin, Yu Zhang, Zhixin Guo, Shengnan Cao, Shigen Ye
• Format: Journal Article
• Language: Korean
• Published: 한국미생물생명공학회 31-10-2024
• Subjects: 2D-LC-MS/MS; antibacterial; aquatic pathogens; Bacillus cereus; lipopeptides
• ISSN: 1017-7825

Screening for antagonistic bacteria on aquatic pathogens and identification of antagonistic ingredients are essential to reduce the use of chemicals in aquaculture. In this study, strain BA09, subsequently identified as Bacillus cereus, simultaneously displayed strong antagonistic effects on Edwardsiella tarda, Vibrio harveyi, and Streptococcus anisopliae in the initial screening and rescreening. In addition, the methanol extract of BA09 was subjected to antibacterial activity verification and one-dimensional (1D) reversed-phase liquid chromatography (RPLC) preparation. A total of 27 fractions were collected, 6 of which were subjected to two-dimensional (2D) RPLC separation and tracked as antibacterial. A total of 14 lipopeptides that included 9 fengycin homologs, 3 bacillomycin homologs, and 2 surfactin homologs were identified by tandem highresolution mass spectrometry. Through characterization of the antibacterial substance in Bacillus cereus BA09, which simultaneously inhibited E. tarda, V. harveyi, and S. agalactiae, the current study provides a theoretical basis for the development of antibacterial drugs in aquaculture.