title: Proteomic analysis of the influence of Cu(2+) on the crystal protein production of Bacillus thuringiensis X022.
abstract: BACKGROUND
  Bacillus thuringiensis X022, a novel strain isolated from soil in China, produces diamond-shaped parasporal crystals. Specific mineral nutrients, such as Mg, Cu, and Mn, influence insecticidal crystal proteins (ICP) expression and the effects of these elements vary significantly. However, the molecular mechanisms of the effects caused by mineral elements have yet to be reported.
  
  
  RESULTS
  The ICP are mainly composed of Cry1Ca, Cry1Ac, and Cry1Da, which have molecular weights of about 130 kDa. ICP production was most efficient when Cu(2+) was added at concentrations ranging from 10(-6) to 10(-4) mol/L at an initial pH of 8.0. Addition of Cu(2+) also evidently increased the toxicity of fermentation broth to Spodoptera exigua and Helicoverpa armigera. After analyzing changes in proteome and fermentation parameters caused by Cu(2+) addition, we propose that Cu(2+) increases PhaR expression and consequently changes the carbon flow. More carbon sources was used to produce intracellular poly-β-hydroxybutyrate (PHB). Increases in PHB as a storage material bring about increases of ICP production.
  
  
  CONCLUSIONS
  Bacillus thuringiensis X022 mainly expresses Cry1Ca, Cry1Ac, and Cry1Da. Cu(2+) increases the expression of Cry1Da, Cry1Ca, and also enhances the toxicity of fermentation broth to S. exigua and H. armigera.
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 157125750@qq.com.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 314097184@qq.com.
authors.forename: Mingxing
authors.initials: M
authors.lastname: Zuo
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 1139956294@qq.com.
authors.forename: Ting
authors.initials: T
authors.lastname: Wang
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. syj6253@hotmail.com.
authors.forename: Yunjun
authors.initials: Y
authors.lastname: Sun
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 281067633@qq.com.
authors.forename: Shuang
authors.initials: S
authors.lastname: Liu
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 6498034@qq.com.
authors.forename: Shengbiao
authors.initials: S
authors.lastname: Hu
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 787400602@qq.com.
authors.forename: Hao
authors.initials: H
authors.lastname: He
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 383109953@qq.com.
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 993216931@qq.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Rang
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. 258375240@qq.com.
authors.forename: Meifang
authors.initials: M
authors.lastname: Quan
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. xialq@hunnu.edu.cn.
authors.forename: Liqiu
authors.initials: L
authors.lastname: Xia
authors.affiliation: College of Life Science, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Hunan Normal University, Changsha, 410081, China. dingxuezhi@hunnu.edu.cn.
authors.forename: Xuezhi
authors.initials: X
authors.lastname: Ding
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000633:toxicity; D019149:Bioreactors; D002244:Carbon / Q000737:chemistry / Q000378:metabolism; D003300:Copper / Q000737:chemistry* / Q000494:pharmacology; D004731:Endotoxins / Q000096:biosynthesis* / Q000737:chemistry / Q000633:toxicity; D006460:Hemolysin Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000633:toxicity; D006863:Hydrogen-Ion Concentration; D006885:Hydroxybutyrates / Q000378:metabolism; D007306:Insecticides / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D007477:Ions / Q000737:chemistry; D008970:Molecular Weight; D009036:Moths / Q000187:drug effects; D010802:Phylogeny; D011091:Polyesters / Q000378:metabolism; D020543:Proteome / Q000187:drug effects; D040901:Proteomics; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D018411:Spodoptera / Q000187:drug effects; D000094122:Polyhydroxybutyrates
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D002244:Carbon; D003300:Copper; D004731:Endotoxins; D006460:Hemolysin Proteins; D006885:Hydroxybutyrates; D007306:Insecticides; D007477:Ions; D011091:Polyesters; D020543:Proteome; D012336:RNA, Ribosomal, 16S; C030956:insecticidal crystal protein, Bacillus Thuringiensis; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates