Carboxyspermidine decarboxylase of the prominent intestinal microbiota species Bacteroides thetaiotaomicron is required for spermidine biosynthesis and contributes to normal growth
Carboxyspermidine decarboxylase of the prominent intestinal microbiota species Bacteroides thetaiotaomicron is required for spermidine biosynthesis and contributes to normal growth
复制标题
DOI：
10.1007/s00726-016-2233-0
复制
发表时间：
2016-10-01
期刊：
影响因子：
3.5
通讯作者：
Kurihara, Shin
中科院分区：
文献类型：
--
作者：
Sakanaka, Mikiyasu;Sugiyama, Yuta;Kurihara, Shin
最近的研究表明，肠道微生物产生的多胺显着影响宿主的健康;然而，除了大肠杆菌，胃肠道微生物群的一个小组成部分，微生物多胺生物合成途径知之甚少。在这里，我们研究了多形拟杆菌，在人类的主要胃肠道细菌物种的多胺生物合成能力。高效液相色谱分析表明，B.在不含多胺的基本培养基中培养的多形核至少在对数中期和稳定期细胞内积累亚精胺。缺失编码推定的羧基亚精胺脱羧酶（casdc）的基因，该酶将羧基亚精胺转化为亚精胺，导致B中亚精胺的耗尽和脱羧酶活性的丧失。太多了。Delta casdc菌株在不含多胺的生长培养基中也显示出生长缺陷。补充的Delta casdc菌株恢复了亚精胺生物合成能力、脱羧酶活性和生长。这些结果表明，羧基亚精胺脱羧酶是必不可少的合成亚精胺在B。这是一个非常重要的因素，有助于该物种的生长。
Recent studies have indicated that polyamines produced by gut microbes significantly influence host health; however, little is known about the microbial polyamine biosynthetic pathway except for that in Escherichia coli, a minor component of the gastrointestinal microbiota. Here, we investigated the polyamine biosynthetic ability of Bacteroides thetaiotaomicron, a predominant gastrointestinal bacterial species in humans. High-performance liquid chromatography analysis revealed that B. thetaiotaomicron cultured in polyamine-free minimal medium accumulated spermidine intracellularly at least during the mid-log and stationary phases. Deletion of the gene encoding a putative carboxyspermidine decarboxylase (casdc), which converts carboxyspermidine to spermidine, resulted in the depletion of spermidine and loss of decarboxylase activity in B. thetaiotaomicron. The Delta casdc strain also showed growth defects in polyamine-free growth medium. The complemented Delta casdc strain restored the spermidine biosynthetic ability, decarboxylase activity, and growth. These results indicate that carboxyspermidine decarboxylase is essential for synthesizing spermidine in B. thetaiotaomicron and contributes to the growth of this species.