title: Detection of toxin proteins from Bacillus thuringiensis strain 4.0718 by strategy of 2D-LC-MS/MS.
abstract: Bacillus thuringiensis is a kind of insecticidal microorganism which can produce a variety of toxin proteins, it is particularly important to find an effective strategy to identify novel toxin proteins rapidly and comprehensively with the discovery of the wild-type strains. Multi-dimensional high-performance liquid chromatography combined with mass spectrometry has become one of the main methods to detect and identify toxin proteins and proteome of B. thuringiensis. In this study, protein samples from B. thuringiensis strain 4.0718 were analyzed on the basis of two-dimensional liquid chromatography-tandem mass spectrometry (2D-LC-MS/MS), and tryptic peptides of whole cell from the late sporulation phase were eluted at different concentration gradients of ammonium chloride and followed by secondary mass spectrum identification. 831 and 894 proteins were identified from two biological replicates, respectively, while 1,770 and 1,859 peptides were detected correspondingly. Among the identified proteins and peptides, 606 proteins and 1,259 peptides were detected in both replicates, which mean that 1,119 proteins and 2,370 peptides were unique to the proteome of this strain. A total of 15 toxins have been identified successfully, and seven of them were firstly discovered in B. thuringiensis strain 4.0718 that were Crystal protein (A1E259), pesticidal protein (U5KS09), Cry2Af1 (A4GVF0), Cry2Ad (Q9RM89), Cry1 (K4HMB5), Cry1Bc (Q45774), and Cry1Ga (Q45746). The proteomic strategy employed in the present study has provided quick and exhaustive identification of toxins produced by B. thuringiensis.
authors.affiliation: Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, China, yangqiaaa@163.com.
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.forename: Sijia
authors.initials: S
authors.lastname: Tang
authors.forename: Jie
authors.initials: J
authors.lastname: Rang
authors.forename: Mingxing
authors.initials: M
authors.lastname: Zuo
authors.forename: Xuezhi
authors.initials: X
authors.lastname: Ding
authors.forename: Yunjun
authors.initials: Y
authors.lastname: Sun
authors.forename: Pinghui
authors.initials: P
authors.lastname: Feng
authors.forename: Liqiu
authors.initials: L
authors.lastname: Xia
mesh_terms: D001413:Bacillus thuringiensis / Q000737:chemistry*; D001426:Bacterial Proteins / Q000032:analysis*; D001427:Bacterial Toxins / Q000032:analysis*; D002853:Chromatography, Liquid; D020543:Proteome / Q000032:analysis; D040901:Proteomics / Q000379:methods*; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D020543:Proteome