Sequence analysis of the Microcystis aeruginosa FACHB-912 phytochrome gene supports positive selection in cyanobacteria  

作　　者：SHI Fei LI Nan LIU ShaoFang QIN Song 

机构地区：[1]Yantai Institute of Coastal Zone Research,Chinese Academy of Sciences,Yantai 264003,China [2]Marine Biotechnology Research Center,Korean Ocean Research&Development Institute,Ansan 425600,Republic of Korea [3]Graduate University of Chinese Academy of Sciences,Beijing 100049,China [4]Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China

出　　处：《Chinese Science Bulletin》2012年第25期3270-3276,共7页

基　　金：supported by the CAS/SAFEA International Partnership Program for Creative Research Teams and a Project of the Chinese Marine Microbial Center (KSCX2-YW-G-073)

摘　　要：The phytochrome gene from Microcystis aeruginosa FACHB-912,isolated from algal blooms in Taihu Lake in China,was sequenced and found to code for a wavelength transition light receptor protein.The gene was composed of five distinct domains:a PAS fold domain,a GAF domain,a phytochrome domain,a His Kinase A(phosphoacceptor) domain,and a histidine kinase domain.Red-absorbing phytochrome,far-red-absorbing phytochrome,and photoconversion kinetics were monitored via the spectral characteristics of the protein.To detect positive selection,homologous sequences from cyanobacterium phytochrome genes were obtained from GenBank.Potential selective pressure was identified by phylogenetic analysis with maximum likelihood analyses.The frequency of the phytochrome gene being subjected to selective constraints suggests that positive selection is a potentially important mechanism that promotes the evolution of the cyanobacteria phytochrome gene.The sites identified in this study provide targets for further research on the structural-functional role of these residues,and on the correlation with the mechanism of algal blooms.The phytochrome gene from Microcystis aeruginosa FACHB-912, isolated from algal blooms in Taihu Lake in China, was sequenced and found to code for a wavelength transition light receptor protein. The gene was composed of five distinct domains： a PAS fold domain, a GAF domain, a phytochrome domain, a His Kinase A （phosphoacceptor） domain, and a histidine kinase domain. Red-absorbing phytochrome, far-red-absorbing phytochrome, and photoconversion kinetics were monitored via the spectral characteristics of the protein. To detect positive selection, homologous sequences from cyanobacterium phytochrome genes were obtained from GenBank. Potential selective pressure was identified by phylogenetic analysis with maximum likelihood analyses. The frequency of the phytochrome gene being subjected to selective constraints suggests that positive selection is a potentially important mechanism that promotes the evolution of the cyanobacteria phytochrome gene. The sites identified in this study pro- vide targets for further research on the structural-functional role of these residues, and on the correlation with the mechanism of algal blooms.

关 键 词：光敏色素 色素基因 铜绿微囊藻 蓝藻水华 正选择 序列分析 GENBANK 组氨酸激酶 

分 类 号：Q943[生物学—植物学]