摘要
群体感应信号(quorum sensing,QS)是细菌的一种特殊交流方式,它具有调节种群密度、生物膜形成、毒素产生以及色素的形成等多种功能。藻菌关系是藻华过程中重要的一环,为了探求藻华过程中信号微生物的动态变化,我们以深圳大鹏湾的锥状斯氏藻(Scrippsiella trochoidea)藻华中的QS菌株为研究对象,应用报告菌株和环境微生物宏基因组方法,监测了藻华爆发期间信号微生物的动态变化过程,并构建了藻类、QS微生物与其它微生物的相关性关系。结果表明:在筛选的QS菌株中经去冗余和重复后成功鉴定了7种不同的细菌,分别是冷杆菌Psychrobacter cryohalolentis、普罗维登斯菌Providencia sneebia、假单胞菌Pseudomonas stutzeri、微小杆菌Exiguobacterium sp.AT1b、产酸克雷伯菌Klebsiella oxytoca、球形赖氨酸芽孢杆菌Lysinibacillus sphaericus和鲍氏不动杆菌Acinetobacter baumannii。相关性分析发现P.sneebia的丰度与藻类数量变化呈正相关,而L.sphaericus和P.stutzeri的丰度与藻类数量变化呈负相关,其它QS微生物中未见显著相关性。综合实验的结果来看,QS微生物在藻际微生物的群体结构中扮演着一定的生态作用,它帮助我们从一个新的视角了解藻华过程中QS微生物的丰度变化和网络关系,为认识藻菌关系提供了新的思路。
Quorum sensing（QS） is a system of stimulus and response correlated to population density in bacteria. Many species of bacteria use QS to coordinate gene expression according to the density of their local population. As a special language, QS was used to regulate a wide range of biological behavior in bacteria such as bioluminescence, virulence factor production, biofilm formation and antibiotic resistance. In phycosphere environment, symbiotic bacteria play important roles in microbes-host relationships. Based on the high diversity and complexity, the algal-bacteria interaction has become the concern of many researchers. In order to explore the dynamic characteristics of the QS bacterium in the process of algal blooms, we collected the environmental samples during the Scrippsiella trochoidea blooming period. Some related work was carried out, including screening QS producers using report strain, monitoring the dynamic change of QS strains, and building the correlative connections between QS bacteria and non-QS individual based on metagenomics sequencing data. After dereplication analysis, seven QS producers were screened from the cultivable bacteria. They were Psychrobacter cryohalolentis, Providencia sneebia, Pseudomonas stutzeri, Exiguobacterium sp. AT1 b, Klebsiella oxytoca, Lysinibacillus sphaericus and Acinetobacter baumannii. The network analysis showed that Providencia sneebia was positively related to algae biomass significantly, while Lysinibacillus sphaericus and Pseudomonas stutzeri exhibited the negative results. No significant correlations were observed between the QS members and non-QS bacteria. Our work found that QS bacteria play a potential role in shaping the microbial population structure in phycosphere environment, and it offers us a new way for better understanding the algae-bacteria interactions from a signal ecological perspective.
出处
《生态科学》
CSCD
2016年第4期23-30,共8页
Ecological Science
基金
国家自然科学基金(41476092)
深圳市科技创新委员会项目(JSGG20140519113458237
JCYJ20150831192329178
CXZZ20150529165045063)
关键词
锥状斯氏藻藻华
菌藻关系
群体感应
藻际环境
Scrippsiella trochoidea bloom
algae–bacteria interaction
quorum sensing
phycosphere environment
