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

Abstract:

[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.

Key words:Biofouling, Bioflims, Pseudoalteromonas issachenkonii, Diketopiperazines