Ma Shuaiqi, Li Shixin, Song Li, Riaz Asma, Huang Ruifeng, Zhou Shaofen, Qiu Jingnan, Chu Zonglin, He Jian
Group of Peptides and Natural Products Research, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China.
J Antibiot (Tokyo). 2025 May 19. doi: 10.1038/s41429-025-00830-x.
A new cyclic tetrapeptide named Cereusitin B (1), along with a number of known cyclic dipeptides was isolated from the fermentation broth of a marine-associated Bacillus sp. I-2. The structure of Cereusitin B, cyclo-(L-phenylalanyl-trans-4-hydroxy-L-prolyl-L-leucyl-L-alanine), was determined through extensive analysis using high-resolution electrospray ionization mass spectrometry and NMR spectral data (1D, 2D NMR), and its identity was further confirmed by Marfey' method and chemical synthesis. The antimicrobial activity tests showed that compound 2 was moderately active against Candida albicans with a MIC value of 125 µg mL, while the other compounds exhibited no antimicrobial activity at the experimental concentrations. In addition, compound 1 showed the ability to inhibit the formation of S. aureus biofilm.
从一株海洋相关芽孢杆菌I-2的发酵液中分离出一种名为仙菜素B（1）的新型环四肽以及多种已知的环二肽。通过高分辨率电喷雾电离质谱和核磁共振光谱数据（一维、二维核磁共振）进行广泛分析，确定了仙菜素B的结构，即环-（L-苯丙氨酰基-反式-4-羟基-L-脯氨酰基-L-亮氨酰基-L-丙氨酸），并通过马尔菲法和化学合成进一步确认了其结构。抗菌活性测试表明，化合物2对白色念珠菌具有中等活性，最低抑菌浓度（MIC）值为125μg/mL，而其他化合物在实验浓度下未表现出抗菌活性。此外，化合物1显示出抑制金黄色葡萄球菌生物膜形成的能力。
