Dataset Information

Stoichiometry and absolute abundance of proteins in the Bacillus cereus spore insoluble fraction determined using a QconCAT approach

ABSTRACT: Spores of Bacillus cereus pose a threat to food safety due to their high resistance to the heat or acid treatments commonly used to make food microbially safe. As spores survive these treatments and later resume growth either on foodstuffs or, after ingestion, upon entering the gut they are capable of producing toxins which cause either vomiting or diarrhea respectively. The outer layers of the spore consist primarily of proteins which may serve as potential biomarkers for detection. In order to quantify proteins in the insoluble fraction of the spore coat, a proteomics approach using a QconCAT reference standard was employed which is the first time this is used in a heterogeneous system. This allowed us to determine the abundance of 21 proteins which spanned across three orders of magnitude and together covered 5.66% ±0.51 of the total spore weight. Classification by abundance resulted in functional characterisation of the protein BC_0987, renamed SasS. Furthermore, protein stoichiometry and determination of the abundance of, for instance, germination mediating enzymes provides useful information for model development. And finally, the four most abundant proteins, CotB1, CotB2, CotX and InhA, are presented to be biomarker candidates containing immunogenic epitopes as predicted by the SVMTriP algorithm and being conveniently located in the outermost layers of the spore.

INSTRUMENT(S): apex ultra

ORGANISM(S): Bacillus Cereus

TISSUE(S): Spore, Endospore

SUBMITTER: Sacha Stelder

LAB HEAD: Chris Gerdinus de Koster

PROVIDER: PXD003569 | Pride | 2018-10-26

REPOSITORIES: Pride

ACCESS DATA

Dataset's files

Source:

Items per page:

1 - 5 of 108

Similar Datasets

Project description:Bacterial spores play an important role in disease initiation, transmission and persistence. The outermost spore layer, the exosporium, is important as it is the first point of contact between the spore and the environment and may be involved in spore adherence, protection and germination. Clostridium sordellii is a highly lethal, spore forming pathogen that causes soft-tissue infections, enteritis and toxic-shock syndrome. Despite the importance of C. sordellii spores in disease, spore proteins from this bacterium have not been defined or interrogated functionally. In this study, we identified the C. sordellii outer spore proteome and two of the identified proteins, CSA and CSB, were characterised using a genetic and phenotypic approach. Both proteins were essential for the correct formation and positioning of the C. sordellii spore coat and exosporium. The absence of CSA reduced sporulation levels and increased spore sensitivity to heat, sodium hydroxide and hydrochloric acid. By comparison, CSB was required for normal levels of spore adherence to cervical, but not vaginal, cells, with csb mutant spores having increased adherence properties. The establishment of a mouse infection model of the gastrointestinal tract for C. sordellii allowed the role of CSA and CSB to be interrogated in an infected host. Following the oral administration of spores to mice, the wild-type strain efficiently colonized the gastrointestinal tract, with the peak of bacterial numbers occurring at one day post-infection. Colonization was reduced by two logs at four days post-infection. By comparison, mice infected with the csb mutant did not show a reduction in bacterial numbers. The absence of CSB therefore allows the csb mutant to persist within the gastrointestinal tract. We conclude that C. sordellii outer spore proteins are important for the structural and functional integrity of spores, and for colonization and persistence during infection. Finally, Clostridium difficile, Bacillus cereus and Bacillus anthracis encode proteins with homology to CSA and CSB but these bacteria produce spores that are structurally dissimilar to those of C. sordellii, and the function of the proteins in these hosts is different to that in C. sordellii. These findings suggest that, despite their homology, spore proteins can have variable functions in different bacterial species which highlights the necessity of studying each spore protein in the cognate species from which it originates.

			Action	DRS
	CW2314.dat	Other
	CW2314.mgf	Mgf
	CW2314_RE1_01_2272.d.zip	Other
	CW2315.dat	Other
	CW2315.mgf	Mgf

Dataset Information

Stoichiometry and absolute abundance of proteins in the Bacillus cereus spore insoluble fraction determined using a QconCAT approach

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets