title: Comparative complete genome sequence analysis of the amino acid replacements responsible for the thermostability of Corynebacterium efficiens.
abstract: Corynebacterium efficiens is the closest relative of Corynebacterium glutamicum, a species widely used for the industrial production of amino acids. C. efficiens but not C. glutamicum can grow above 40 degrees C. We sequenced the complete C. efficiens genome to investigate the basis of its thermostability by comparing its genome with that of C. glutamicum. The difference in GC content between the species was reflected in codon usage and nucleotide substitutions. Our comparative genomic study clearly showed that there was tremendous bias in amino acid substitutions in all orthologous ORFs. Analysis of the direction of the amino acid substitutions suggested that three substitutions are important for the stability of the C. efficiens proteins: from lysine to arginine, serine to alanine, and serine to threonine. Our results strongly suggest that the accumulation of these three types of amino acid substitutions correlates with the acquisition of thermostability and is responsible for the greater GC content of C. efficiens.
authors.affiliation: Fermentation & Biotechnology Laboratories, Ajinomoto Co., Inc., Kawasaki, Kanagawa 210-8681, Japan.
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Nishio
authors.forename: Yoji
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kawarabayasi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Usuda
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Kimura
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sugimoto
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Matsui
authors.forename: Akihiko
authors.initials: A
authors.lastname: Yamagishi
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kikuchi
authors.forename: Kazuho
authors.initials: K
authors.lastname: Ikeo
authors.forename: Takashi
authors.initials: T
authors.lastname: Gojobori
mesh_terms: D000595:Amino Acid Sequence / Q000235:genetics; D019943:Amino Acid Substitution / Q000235:genetics*; D000596:Amino Acids / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001482:Base Composition / Q000235:genetics; D003062:Codon / Q000235:genetics / Q000378:metabolism; D019295:Computational Biology; D003352:Corynebacterium / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D016680:Genome, Bacterial; D006358:Hot Temperature; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000379:methods
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D003062:Codon; D004269:DNA, Bacterial