title: Characterization of the ask-asd operon in aminoethoxyvinylglycine-producing Streptomyces sp. NRRL 5331.
abstract: The first two genes of the threonine pathway, ask and asd, were cloned and sequenced from the aminoethoxyvinylglycine-producing Streptomyces sp. NRRL 5331. The two genes are organized in a bicistronic operon. ask, encoding the apartokinase (ASK), is located upstream from asd. The presence of a ribosome-binding site within the ask sequence suggests that this open reading frame encodes two overlapping proteins. The formation of both subunits of the aspartokinase from a single gene was studied using antibodies raised against the C-terminal end of the aspartokinase subunits. Disruption of asd results in a significant decrease of aminoethoxyvinylglycine production, thus supporting the involvement of the ask-asd operon in the biosynthesis of this metabolite. This is the first report in which a gene cluster for the first two steps of aminoethoxyvinylglycine biosynthesis is characterized.
authors.affiliation: Instituto de Biotecnología de León INBIOTEC, Parque Científico de León, Avda. del Real no. 1, 24006, León, Spain.
authors.forename: Y
authors.initials: Y
authors.lastname: Cuadrado
authors.forename: M
authors.initials: M
authors.lastname: Fernández
authors.forename: E
authors.initials: E
authors.lastname: Recio
authors.forename: J F
authors.initials: JF
authors.lastname: Aparicio
authors.forename: J F
authors.initials: JF
authors.lastname: Martín
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001222:Aspartate Kinase / Q000096:biosynthesis / Q000235:genetics*; D001223:Aspartate-Semialdehyde Dehydrogenase / Q000096:biosynthesis / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D018387:Codon, Initiator; D018388:Codon, Terminator; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D017353:Gene Deletion; D015870:Gene Expression; D023061:Gene Order; D005798:Genes, Bacterial; D005807:Genes, Overlapping; D005998:Glycine / Q000031:analogs & derivatives* / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics*; D008969:Molecular Sequence Data; D009876:Operon; D012333:RNA, Messenger / Q000032:analysis; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013302:Streptomyces / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D018387:Codon, Initiator; D018388:Codon, Terminator; D004269:DNA, Bacterial; D012333:RNA, Messenger; D001223:Aspartate-Semialdehyde Dehydrogenase; D001222:Aspartate Kinase; C088137:aminoethoxyvinylglycine; D005998:Glycine