摘要
从云南省泸西县的污水处理厂分离到一株菌胶团形成菌YN12,经过鉴定与象牙白伪杜擀氏菌(Pseudoduganella eburnea)10R5-21T模式株具有较近的亲缘关系,属于同一物种。为揭示该菌株与其他活性污泥细菌间菌胶团形成机制及碳源利用方面的异同,对该菌株进行全基因组测序、组装、注释及比较基因组学分析。结果表明:P. eburnea YN12株基因组大小约为5934 kb, G+C含量为63.9%,包含5313个蛋白质编码序列,具有与喜树脂动胶菌(Zoogloea resiniphila)MMB株、解叔丁醇水居菌(Aquincola tertiaricarbonis)RN12株及解壳聚糖松江菌(Mitsuaria chitosanitabida)XHY-A6株相似的胞外多糖生物合成途径、PrsK-PrsR双组分系统和PEP-CTERM胞外蛋白家族,共同介导和调控的菌胶团形成机制。与后者相比,菌株YN12中胞外多聚物(Extracellular polymeric substances, EPS)形成相关基因集中在大小约为72 kb的大型基因簇上,且能吸收利用的碳源特别是单糖、二糖和多糖更为丰富多样。同时,我们还从河流及养殖水体中也分离到象牙白伪杜擀氏菌,这些菌株可用于生物絮团技术(Biofloc Technology),改善水产养殖水质。
In activated sludge process the separation of sludge and water is achieved by gravity, and the floc-forming bacteria are predominated and play a central role in the water purification. In this study, a floc-forming bacterial strain YN12 was isolated from activated sludge of the municipal sewage treatment plant of Luxi County, Yunnan Province,and it was identified as Pseudoduganella eburnean and was phenotypically similar to the type strain 10 R5-21 T. In order to reveal and compare the floc-forming mechanism and carbon source utilization of the strain YN12 with those of other floc-forming bacteria, the genome sequencing, assembly, annotation and comparative genomics analysis were conducted. The results showed that the genome size of Pseudoduganella eburnea YN12 was about 5934 kb, the G+C content was 63.9%, and it contained 5313 protein coding sequences. Comparative analyses revealed a similar floc-forming and regulation mechanism to Zoogloea resiniphila MMB, Aquincola tertiaricarbonis RN12 and Mitsuaria chitosanitabida XHY-A6, which involves the exopolysaccharide biosynthesis, PrsK-PrsR two-component system and PEPCTERM domain containing protein family. Meanwhile, these genes involved in the synthesis of extracellular polymeric substances(EPS) were concentrated on a large gene cluster of about 72 kb in size, and the YN12 strain was more functionally diverse in the absorption and utilization of carbon sources, particularly monosaccharides, disaccharides and polysaccharides. Moreover, two other Pseudoduganella eburnea strains had also been isolated from a river and an aquaculture pond. It is suggested that these strains could also be utilized in biofloc technology to improve the water quality and nutrient recycling in aquaculture.
作者
刘亚琦
刘双元
高娜
戴景程
邱东茹
LIU Ya-Qi;LIU Shuang-Yuan;GAO Na;DAI Jing-Cheng;QIU Dong-Ru(College of Fisheries and Life Science,Dalian Ocean University,Dalian 116023,China;Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《水生生物学报》
CAS
CSCD
北大核心
2020年第3期655-662,共8页
Acta Hydrobiologica Sinica
基金
中国科学院先导项目“美丽中国”子课题(XDA23040401)
中国科学院重点部署项目(KFZD-SW-219-3-2)资助。
关键词
伪杜擀氏菌属
菌胶团形成
胞外多聚物
活性污泥
全基因组
生物絮团技术
Pseudoduganella
Floc/biofloc formation
Extracellular polymeric substance
Activated sludge
Genome
Biofloc technology
