Dataset Information

MS identification of the Cry proteins in Bacillus thuringiensis CT-43

ABSTRACT: In Bacillus thuringiensis CT-43, five insecticidal crystal proteins (ICPs, Cry protein) are encoded. We extracted the Cry proteins, ran the SDS PAGE (two Cry protein bands were observed), and tried to identify the composition of the two Cry protein bands in the SDS PAGE. The bioinformatics pipeline is described as follows: First, we converted the original mass spectrum files to the mgf file (peaks file), then the mgf files were searched against the Bacillusthuringiensis CT-43 protein database using Mascot (version 2.3.02). The search parameters were: i) trypsin was chosen as the enzyme with one missed cleavage allowed; ii) the fixed modifications of carbamidomethylation were set as Cys, and variable modifications of oxidation as Met; iii) peptide tolerance was set as 0.05 Da, and MS/MS tolerance was set as 0.1 Da. The peptide charge was set as Mr, and monoisotopic mass was chosen. An automatic decoy database search strategy was employed to estimate the false discovery rate (FDR). The FDR was calculated as the false positive matches divided by the total matches. In the final search results, the FDR was less than 1.5%.

INSTRUMENT(S): LTQ Orbitrap, TripleTOF 5600

ORGANISM(S): Bacillus Thuringiensis

TISSUE(S): Whole Body

SUBMITTER: Jieping Wang

LAB HEAD: Jin He

PROVIDER: PXD000425 | Pride | 2020-01-24

REPOSITORIES: Pride

ACCESS DATA

Dataset's files

Source:

			Action	DRS
	PRIDE_Exp_Complete_Ac_30652.pride.mgf.gz	Mgf
	PRIDE_Exp_Complete_Ac_30652.pride.mztab.gz	Mztab
	PRIDE_Exp_Complete_Ac_30652.xml.gz	Xml
	PRIDE_Exp_Complete_Ac_30653.pride.mgf.gz	Mgf
	PRIDE_Exp_Complete_Ac_30653.pride.mztab.gz	Mztab

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Publications

Expression profile and regulation of spore and parasporal crystal formation-associated genes in Bacillus thuringiensis.

Wang Jieping J Mei Han H Qian Hongliang H Tang Qing Q Liu Xiaocui X Yu Ziniu Z He Jin J

Journal of proteome research 20131118 12

Bacillus thuringiensis, a Gram-positive endospore-forming bacterium, is characterized by the formation of parasporal crystals consisting of insecticidal crystal proteins (ICPs) during sporulation. We reveal gene expression profiles and regulatory mechanisms associated with spore and parasporal crystal formation based on transcriptomics and proteomics data of B. thuringiensis strain CT-43. During sporulation, five ICP genes encoded by CT-43 were specifically transcribed; moreover, most of the spo ...[more]

PMID: 24215520

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