title: Proteome responses of Citrobacter werkmanii BF-6 planktonic cells and biofilms to calcium chloride.
abstract: Calcium ions are well-known as intracellular second messengers that also have an important extracellular structural role for bacteria. Recently, we found that denser biofilms were formed by Citrobacter werkmanii BF-6 in the presence of 400 mM Ca(2+) than that of 12.5mM Ca(2+). Therefore, we employed two-dimensional (2-D) electrophoresis methods to investigate the proteome profiles of planktonic cells and biofilms in BF-6 under different concentrations of Ca(2+). Meanwhile, BF-6 biofilm architecture was also visualized with confocal laser scanning microscopy (CLSM). The results demonstrated that BF-6 biofilms formed at the bottom of microtiter plates when grown in the presence of 400 mM Ca(2+). A total of 151 proteins from planktonic cells and biofilms after exposure of BF-6 cells to 12.5 and 400 mM Ca(2+) were successfully identified. Different gene ontology (GO) and KEGG pathways were categorized and enriched for the above proteins. Growth in the presence of 400 mM Ca(2+) induced more complex signal pathways in BF-6 than 12.5mM Ca(2+). In addition, the biofilm architectures were also affected by Ca(2+). Our results show two different modes of biofilm enhancement for C. werkmanii in the presence of excess Ca(2+) and provide a preliminary expression of these differences based on proteomic assays.
authors.affiliation: Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, People's Republic of China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou, Guangdong 510070, People's Republic of China; Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangzhou, Guangdong 510070, People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Zhou
authors.affiliation: Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, People's Republic of China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou, Guangdong 510070, People's Republic of China; Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangzhou, Guangdong 510070, People's Republic of China. Electronic address: shiqingshan@hotmail.com.
authors.forename: Qing-Shan
authors.initials: QS
authors.lastname: Shi
authors.affiliation: Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, People's Republic of China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou, Guangdong 510070, People's Republic of China; Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangzhou, Guangdong 510070, People's Republic of China.
authors.forename: Xiao-Mo
authors.initials: XM
authors.lastname: Huang
authors.affiliation: Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, People's Republic of China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou, Guangdong 510070, People's Republic of China; Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangzhou, Guangdong 510070, People's Republic of China.
authors.forename: Xiao-Bao
authors.initials: XB
authors.lastname: Xie
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis*; D018441:Biofilms / Q000254:growth & development*; D002122:Calcium Chloride / Q000494:pharmacology*; D002954:Citrobacter / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D020543:Proteome / Q000096:biosynthesis*
chemical_list: D001426:Bacterial Proteins; D020543:Proteome; D002122:Calcium Chloride
keywords: Biofilm formation; Calcium ions; Citrobacter werkmanii; Confocal laser scanning microscopy (CLSM); Proteomic response