title: Assessment of protoxin composition of Bacillus thuringiensis strains by use of polyacrylamide gel block and mass spectrometry.
abstract: Assessment of protoxin composition in Bacillus thuringiensis parasporal crystals is principally hampered by the fact that protoxins in a single strain usually possess high sequence homology. Therefore, new strategies towards the identification of protoxins have been developed. Here, we established a powerful method through embedding solubilized protoxins in a polyacrylamide gel block coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of in-gel-generated peptides for protoxin identification. Our model study revealed that four protoxins (Cry1Aa, Cry1Ab, Cry1Ac and Cry2Aa) and six protoxins (Cry4Aa, Cry4Ba, Cry10Aa, Cry11Aa, Cyt1Aa, and Cyt2Ba) could be rapidly identified from B. thuringiensis subsp. kurstaki HD1 and subsp. israelensis 4Q2-72, respectively. The experimental results indicated that our method is a straightforward tool for analyzing protoxin expression profile in B. thuringiensis strains. Given its technical simplicity and sensitivity, our method might facilitate the present screening program for B. thuringiensis strains with new insecticidal properties.
authors.affiliation: College of Life Science, Hunan Normal University, Changsha, PR China.
authors.forename: Zujiao
authors.initials: Z
authors.lastname: Fu
authors.forename: Yunjun
authors.initials: Y
authors.lastname: Sun
authors.forename: Liqiu
authors.initials: L
authors.lastname: Xia
authors.forename: Xuezhi
authors.initials: X
authors.lastname: Ding
authors.forename: Xiangtao
authors.initials: X
authors.lastname: Mo
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Li
authors.forename: Kexue
authors.initials: K
authors.lastname: Huang
authors.forename: Youming
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000180:Acrylic Resins; D001413:Bacillus thuringiensis / Q000737:chemistry* / Q000378:metabolism; D001427:Bacterial Toxins / Q000737:chemistry* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D013058:Mass Spectrometry / Q000379:methods*; D008970:Molecular Weight; D011498:Protein Precursors / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000180:Acrylic Resins; C029103:Bacillus thuringiensis protoxin; D001427:Bacterial Toxins; D011498:Protein Precursors; C016680:polyacrylamide gels