L-Glutamate production by lysozyme-sensitive

Background A non-pathogenic species of coryneform bacteria, Corynebacterium glutamicum, was originally isolated as an L-glutamate producing bacterium and is now used for fermentative production of various amino acids. A mutation in the C. glutamicum ltsA gene caused susceptibility to lysozyme, temperature-sensitive growth, and L-glutamate production. Results The characteristics of eight lysozyme-sensitive mutants which had been isolated after N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis were examined. Complementation analysis with the cloned wild-type ltsA gene and DNA sequencing of the ItsA region revealed that four mutants had a mutation in the ltsA gene. Among them, two mutants showed temperature-sensitive growth and overproduced L-glutamate at higher temperatures, as well as the previously reported ltsA mutant. Other two showed temperature-resistant growth: one missense mutant produced L-glutamate to some extent but the other nonsense mutant did not. These two mutants remained temperature-resistant in spite of introduction of ltsA::kan mutation that causes temperature-sensitive growth in the wild-type background. Conclusions These results indicate that a defect caused by the ltsA mutations is responsible for temperature-sensitive growth and L-glutamate overproduction by C. glutamicum. The two temperature-resistant mutants seem to carry suppressor mutations that rendered cells temperature-resistance and abolished L-glutamate overproduction.

                                            [
  "009:25"
]
                                        

                                            {
  "fn": "NIH",
  "@type": "vcard:Contact",
  "hasEmail": "mailto:info@nih.gov"
}
                                        

                                            [
  {
    "@type": "dcat:Distribution",
    "title": "Official Government Data Source",
    "mediaType": "text/html",
    "description": "Visit the original government dataset for complete information, documentation, and data access.",
    "downloadURL": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC59659/"
  }
]
                                        

                                            [
  "amino-acid-fermentation",
  "corynebacterium-glutamicum",
  "l-glutamate-production",
  "lysozyme-sensitivity",
  "nih"
]
                                        

                                            [
  "009:033"
]
                                        

                                            {
  "name": "National Institutes of Health",
  "@type": "org:Organization"
}
                                        

                                            [
  "NIH"
]