污损生物膜细菌Pseudoalteromonas issachenkonii YT1305-1的鉴定及其代谢物化学成分分析

【目的】对污损生物膜细菌YT1305-1进行菌种鉴定;研究其作为污损生物膜优势菌之一的代谢产物。【方法】通过16S rRNA基因序列分析,结合系统进化树和细菌生理生化实验对菌种进行鉴定,通过硅胶柱层析分离方法和核磁共振检测技术分析其代谢物的化学成分。【结果】发现生物膜中存在明显的优势菌株,假交替单胞菌属为优势菌属之一。16S rRNA序列比对分析表明Pseudoalteromonas issachenkonii为优势菌种之一,将目标菌种命名为Pseudoalteromonas issachenkonii YT1305-1,对其代谢物化学成分进行分析,共得到10个化合物,其中包括5个二酮哌嗪(DKPs)类信号分子,环(甘氨酸-丙氨酸)(1)、环(脯氨酸-甘氨酸)(2)、环(脯氨酸-酪氨酸)(3)、环(4-羟基-脯氨酸-亮氨酸)(4)和环(4-羟基-脯氨酸-丙氨酸)(5),以及尿嘧啶(6)、胸腺嘧啶(7)、胸腺嘧啶脱氧核苷(8)、己二酸二(2-乙基己)酯(9)和邻苯二甲酸二(2-乙基己)酯(10)。【结论】污损生物膜中存在明显的优势菌,其中之一为P.issachenkonii YT1305-1,在其代谢产物中发现了疑似信号分子的物质DKPs,有研究表明该物质能调控生物膜的形成,进而影响生物污损的形成,为探究生物污损现象奠定了物质基础。

Identification of biofouling biofilms bacterium Pseudoalteromonas issachenkonii YT1305-1 and analysis on chemical constitutents of its metabolites

[Objective] Bacterium YT1305-1 was isolated and identified from biofouling biofilms. As one of the dominant bacteria in biofouling biofilms, metabolites of bacterium YT1305-1 were investigated. [Methods] 16S rRNA gene analysis, phylogenetic tree analysis and physiological and biochemical characteristics were carried on to identify the targeted bacterium. Chemical constituents of the bacterial metabolites were purified through silica column chromatography and identified using nuclear magnetic resonance (NMR). [Results] There existed dominant bacterial species in biofouling biofilms. Pseudoalteromonas sp. was identified as one of the dominant species in biofouling bacteria. 16S rRNA analysis showed P. issachenkonii was one the dominant bacterium. The targeted bacterium was named Pseudoalteromonas issachenkonii YT1305-1 and 10 chemicals were identified from its fermentation broth, including 5 Diketopiperazines (DKPs): cyclo (Gly-Ala) (1), cyclo (Pro-Gly) (2), cyclo(Pro-Tyr) (3), cyclo(Leu-4-hydroxyl-Pro) (4), cyclo (Ala-4-hydroxyl-Pro) (5) and uracil (6), thymine (7), thymidine (8), bis (2-ethylhexyl) adipate (9), phthalate esters (2-ethyl caproic) (10). [Conclusion] There existed bacterial species that were obviously dominant in quantitative terms in biofouling bioflims. Bacterium YT1305-1 was purified as one of the dominant bacterium. Analysis on its metabolites identified several DKPs, which might influence the formation of biofilms and further the development of biofouling. This investigation provides material basis for biofouling studies.