Characterization of heat-labile toxin-subunit B from Escherichia coli by liquid chromatography-electrospray ionization-mass spectrometry and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

6533b832fe1ef96bd129a3df

RESEARCH PRODUCT

Characterization of heat-labile toxin-subunit B from Escherichia coli by liquid chromatography-electrospray ionization-mass spectrometry and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

C. De Simone Isabel Sospedra Jordi Mañes Pasquale Ferranti José Miguel Soriano Alberto Ritieni

subject

Spectrometry Mass Electrospray Ionization Electrospray ionization Protein subunit Bacterial Toxins Molecular Sequence Data Toxicology Mass spectrometry medicine.disease_cause spettroemtria di massa Pichia Pichia pastoris Enterotoxins Protein sequencing Enterotoxigenic Escherichia coli medicine Trypsin Amino Acid Sequence Disulfides Phosphorylation Escherichia coli tossina Chromatography Molecular mass biology Chemistry Escherichia coli Proteins E. coli General Medicine biology.organism_classification Recombinant Proteins Molecular Weight Protein Subunits Spectrometry Mass Matrix-Assisted Laser Desorption-Ionization Food Science Chromatography Liquid

description

The possibilities of characterizing the heat-labile enterotoxin (LT) of enterotoxigenic Escherichia coli (ETEC) by liquid chromatography electrospray mass spectrometry (LC/ESI-MS) and matrix-assisted laser desorption with time-of-flight mass spectrometry (MALDI-TOF-MS) were investigated. The B subunit from recombinant E. coli (expression in Pichia pastoris) can be detected by LC/ESI-MS expressed in P. pastoris and the charge envelope signals can be observed; LC/ESI-MS and MALDI-TOF-MS analysis allowed the acquisition of labile toxin subunit B (LTB) molecular weight and preliminary structural characterization of LTB toxin. MALDI-TOF analysis after reduction and alkylation of the protein evidenced the presence of one disulfide bond in the structure of the protein. Confirmatory analysis was carried out by detection of most of the tryptic fragments of the B subunit by MALDI-TOF-MS, obtaining total coverage of the protein sequence. Possible biovariations in the toxin can mostly be determined by sequencing, where an increase of molecular mass in the N-terminal side of the protein was identified. This modification may be due to an O-GlcNAc-1-phosphorylation.

year	journal	country	edition	language
2012-01-01	Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association

10.1016/j.fct.2012.08.014 https://pubmed.ncbi.nlm.nih.gov/22921353