Project description:The demand for alternative sources of food proteins is increasing due to the limitations and challenges associated with conventional food production. Advances in biotechnology have enabled the production of proteins using microorganisms, thus prompting the exploration of attractive microbial hosts capable of producing functional proteins in high titers. Corynebacterium glutamicum is widely used in industry for the production of amino acids and has many advantages as a host organism for recombinant protein production. However, its performance in this area is limited by low yields of target proteins and high levels of native protein secretion. Despite representing a challenge for heterologous protein production, the C. glutamicum secretome has not been fully characterized. In this study, state-of-the-art mass spectrometry-based proteomics was used to identify and analyze the proteins secreted by C. glutamicum. Both the wild-type strain and a strain that produced and secreted a recombinant ß-lactoglobulin protein were analyzed. A total of 427 proteins were identified in the culture supernatants, with 148 predicted to possess a secretion signal peptide. The top 12 most abundant proteins accounted for almost 80% of the secretome. These are uncharacterized proteins of unknown function, resuscitation promoting factors, protein PS1, Porin B, ABC-type transporter protein and hypothetical membrane protein. The data from this study can provide valuable insight for researchers looking to improve protein secretion and optimize C. glutamicum as a host for secretory protein production.
Project description:Comparative genomic hybridization microarrays featuring overlapping probes spanning the entire C. botulinum type A1 strain ATCC 3502 genome were used to identify regions whose presence are variable among a diverse panel of type A C. botulinum strains.
Project description:Investigation of whole genome gene expression level changes in Yersinia intermedia strain ATCC 29909 in response to oxygen. The experiments and results have not been published yet (manuscript has been submitted to journal office and is under revision)
Project description:Corynebacterium glutamicum strain ATCC 21831 is a producer of L-arginine that was created by random mutagenesis. It is resistant to the arginine structural analogue canavanine. In order to identify potential bottlenecks in the biosynthetic pathway that leads to this industrially important amino acid, relative metabolite abundances of biosynthetic intermediates were determined in comparison to the type strain ATCC 13032. An extract of U13C-labeled biomass was used as internal standard, to correct for different ionization efficiencies. Metabolites were identified using the ALLocator web platform.
Project description:Pathogenic bacteria Yersinia enterocolitica injects virulence plasmid-encoded effectors through the type three secretion system into macrophages to modulate gene expression. At this point it is not known whether epigenetic modifications play a role in Yersinia regulation of gene expression. To answer this question primary human macrophages were infected with mock, WAC (virulence plasmid-cured strain) or WA314 (wild type) and samples were subjected to ChIP-seq for H3K4me3, H3K4me1, H3K27ac and H3K27me3. The effect of effector proteins YopM and YopP on histone modifications in macrophages was analyzed using a wild type strain lacking either YopM or YopP and subsequent ChIP-seq analysis.
