Comparative complete genome sequence analysis of the amino acid replacements responsible for the thermostability of Corynebacterium efficiens.
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.
Nishio
Yousuke
Y
Fermentation & Biotechnology Laboratories, Ajinomoto Co., Inc., Kawasaki, Kanagawa 210-8681, Japan.
Nakamura
Yoji
Y
Kawarabayasi
Yutaka
Y
Usuda
Yoshihiro
Y
Kimura
Eiichiro
E
Sugimoto
Shinichi
S
Matsui
Kazuhiko
K
Yamagishi
Akihiko
A
Kikuchi
Hisashi
H
Ikeo
Kazuho
K
Gojobori
Takashi
T
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
D000596:Amino Acids; D001426:Bacterial Proteins; D003062:Codon; D004269:DNA, Bacterial