Laboratory of Microbiology, Department of Seafood Science, National Kaohsiung Marine University, No. 142, Hai-Chuan Rd., Nan-Tzu, Kaohsiung City 811, Taiwan.
Enzyme Microb Technol. 2011 Sep 10;49(4):372-9. doi: 10.1016/j.enzmictec.2011.06.016. Epub 2011 Jun 28.
A brownish yellow pigmented bacterial strain, designated antisso-27, was recently isolated from a water area of saltpan in Southern Taiwan. Phylogenetic analyses based on 16S rRNA gene sequences indicate that strain antisso-27 belongs the genus Aquimarina in the family Flavobacteriacea and its only closest neighbor is Aquimarina spongiae (96.6%). Based on screening for algicidal activity, strain antisso-27 exhibits potent activity against the toxic cyanobacterium Microcystis aeruginosa. Both the strain antisso-27 bacterial culture and its culture filtrate show algicidal activity against the toxic cyanobacterium, indicating that an algicidal substance is released from strain antisso-27. The algicidal activity of strain antisso-27 occurs during the late stationary phase of bacterial growth. Strain antisso-27 can synthesize an algicidal protein with a molecular mass of 190 kDa, and its isoelectric point is approximately 9.4. This study explores the nature of this algicidal protein such as L-amino acid oxidase with broad substrate specificity. The enzyme is most active with L-leucine, L-isoleucine, L-methionine and L-valine and the hydrogen peroxide generated by its catalysis mediates algicidal activity. This is the first report on an Aquimarina strain algicidal to the toxic M. aeruginosa and the algicidal activity is generated through its enzymatic activity of L-amino acid oxidase.
最近，从台湾南部盐田的一个水域中分离到一株呈棕黄色的细菌菌株，命名为 antisso-27。基于 16S rRNA 基因序列的系统发育分析表明，菌株 antisso-27 属于黄杆菌科的 Aquimarina 属，与 Aquimarina spongiae 的亲缘关系最近（96.6%）。根据对杀藻活性的筛选，菌株 antisso-27 对有毒的蓝藻铜绿微囊藻表现出很强的活性。菌株 antisso-27 的细菌培养物及其培养滤液均对有毒的蓝藻表现出杀藻活性，表明菌株 antisso-27 释放出一种杀藻物质。菌株 antisso-27 的杀藻活性发生在细菌生长的晚期静止期。菌株 antisso-27 可以合成一种分子量为 190 kDa 的杀藻蛋白，等电点约为 9.4。本研究探讨了这种杀藻蛋白的性质，如具有广泛底物特异性的 L-氨基酸氧化酶。该酶对 L-亮氨酸、L-异亮氨酸、L-蛋氨酸和 L-缬氨酸最具活性，其催化产生的过氧化氢介导杀藻活性。这是首次报道 Aquimarina 菌株对有毒的 M. aeruginosa 具有杀藻活性，并且这种杀藻活性是通过其 L-氨基酸氧化酶的酶活性产生的。
