Ding Lianshuai, Zhang Song, Guo Wenbin, Chen Xinhua
Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, P.R. China.
Fujian Key Laboratory of of Marine Genetic Resources, Xiamen 361005, P.R. China.
J Microbiol Biotechnol. 2018 May 28;28(5):784-795. doi: 10.4014/jmb.1712.12014.
Pc3 was isolated from Antarctic seawater with antifungal activity. In order to investigate the metabolic regulation mechanism in the biosynthesis of lipopeptides in Pc3, GC/MS-based metabolomics was used when exogenous indole was added. The intracellular metabolite profiles showed decreased asparagine, aspartic acid, glutamine, glutamic acid, threonine, valine, isoleucine, hexadecanoic acid, and octadecanoic acid in the indole-treated groups, which were involved in the biosynthesis of lipopeptides. Pc3 exhibited a growth promotion, bacterial total protein increase, and lipopeptide biosynthesis inhibition upon the addition of indole. Besides this, real-time PCR analysis further revealed that the transcription of lipopeptide biosynthesis genes , and were downregulated by indole with 22.4-, 21.98-, and 26.0-fold, respectively. It therefore was speculated that as the metabolic flux of most of the amino acids and fatty acids were transferred to the synthesis of proteins and biomass, lipopeptide biosynthesis was weakened owing to the lack of precursor amino acids and fatty acids.
Pc3是从具有抗真菌活性的南极海水中分离出来的。为了研究Pc3中脂肽生物合成的代谢调控机制，在添加外源吲哚时采用了基于气相色谱/质谱联用的代谢组学方法。细胞内代谢物谱显示，在吲哚处理组中，参与脂肽生物合成的天冬酰胺、天冬氨酸、谷氨酰胺、谷氨酸、苏氨酸、缬氨酸、异亮氨酸、十六烷酸和十八烷酸减少。添加吲哚后，Pc3表现出生长促进、细菌总蛋白增加和脂肽生物合成抑制。除此之外，实时定量聚合酶链反应分析进一步表明，脂肽生物合成基因、和的转录分别被吲哚下调了22.4倍、21.98倍和26.0倍。因此推测，由于大多数氨基酸和脂肪酸的代谢通量转移到蛋白质和生物量的合成中，脂肽生物合成因缺乏前体氨基酸和脂肪酸而减弱。
