title: Aspartate aminotransferase is involved in cold adaptation in psychrophilic Pseudomonas syringae.
abstract: CSM2, a cold-sensitive mutant of psychrophilic Pseudomonas syringae, grows like wild-type cells when cultured at 22 and 28 degrees C; but at 4 degrees C, the growth is retarded. In CSM2, AAT (coding for aspartate aminotransferase) is identified as the mutated gene. The expression of AAT in Pseudomonas syringae was transiently enhanced when cells were shifted from 22 to 4 degrees C indicating that AAT is cold-inducible. Complementation of the mutated AAT transformed CSM2 from a cold-sensitive phenotype to a cold-resistant phenotype like the wild-type cells, thus providing evidence for the first time that AAT is required for low-temperature growth.
authors.affiliation: Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India.
authors.forename: V R
authors.initials: VR
authors.lastname: Sundareswaran
authors.forename: Ashish Kumar
authors.initials: AK
authors.lastname: Singh
authors.forename: Smita
authors.initials: S
authors.lastname: Dube
authors.forename: S
authors.initials: S
authors.lastname: Shivaji
mesh_terms: D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D001219:Aspartate Aminotransferases / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D003080:Cold Temperature; D004269:DNA, Bacterial / Q000235:genetics; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009154:Mutation; D010802:Phylogeny; D044224:Pseudomonas syringae / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D016415:Sequence Alignment; D024363:Transcription Initiation Site
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D001219:Aspartate Aminotransferases