title: Organization and regulation of the Corynebacterium glutamicum hom-thrB and thrC loci.
abstract: The genes encoding the three terminal enzymes in the threonine biosynthetic pathway, homoserine dehydrogenase (hom), homoserine kinase (thrB) and threonine synthase (thrC) have been isolated from Corynebacterium glutamicum. The C. glutamicum hom and thrB genes were subcloned on a 3.6 kb SalI-generated chromosomal fragment. The C. glutamicum thrC gene was shown not to be linked to the hom-thrB locus. L-methionine represses the cloned homoserine dehydrogenase and homoserine kinase similar to that of the chromosomally encoded hom and thrB gene products. Northern hybridization analysis demonstrates that this repression is mediated at the level of transcription and that hom-thrB represents an operon in C. glutamicum.
authors.affiliation: Department of Applied Biological Sciences, Massachusetts Institute of Technology, Cambridge 02139.
authors.forename: M T
authors.initials: MT
authors.lastname: Follettie
authors.forename: H K
authors.initials: HK
authors.lastname: Shin
authors.forename: A J
authors.initials: AJ
authors.lastname: Sinskey
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics*; D019757:Carbon-Oxygen Lyases; D002876:Chromosomes, Bacterial / Q000502:physiology; D003352:Corynebacterium / Q000201:enzymology / Q000235:genetics*; D004262:DNA Restriction Enzymes; D005796:Genes; D005798:Genes, Bacterial; D005809:Genes, Regulator; D005838:Genotype; D006715:Homoserine Dehydrogenase / Q000235:genetics*; D008190:Lyases / Q000235:genetics*; D010770:Phosphotransferases / Q000235:genetics*; D017853:Phosphotransferases (Alcohol Group Acceptor); D010957:Plasmids
chemical_list: D000429:Alcohol Oxidoreductases; D006715:Homoserine Dehydrogenase; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); C021370:homoserine kinase; D004262:DNA Restriction Enzymes; D008190:Lyases; D019757:Carbon-Oxygen Lyases; C023160:threonine synthase