title: Induction of saccharolytic enzymes by sucrose in Bacillus subtilis: evidence for two partially interchangeable regulatory pathways.
abstract: Sucrose induces two saccharolytic enzymes in Bacillus subtilis, an intracellular sucrase and an extracellular levansucrase, encoded by sacA and sacB, respectively. It was previously shown that the sacY gene encodes a positive regulator involved in a sucrose-dependent antitermination upstream from the sacB coding sequence. We show here that the sacY product is not absolutely required for sacB induction: a weak but significant induction can be observed in strains harboring a sacY deletion. The sacY-independent induction was altered by mutations located in the sacP and sacT loci but was observed in both sacU+ and sacU32 genetic backgrounds. These results suggest that B. subtilis has two alternative systems allowing sacB induction by sucrose. Both systems also seem to be involved in sacA induction.
authors.affiliation: Laboratoire de Génétique des Microorganismes, Institut National de la Recherche Agronomique, Thiverval-Grignon, France.
authors.forename: M
authors.initials: M
authors.lastname: Steinmetz
authors.forename: D
authors.initials: D
authors.lastname: Le Coq
authors.forename: S
authors.initials: S
authors.lastname: Aymerich
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D004790:Enzyme Induction; D005786:Gene Expression Regulation / Q000187:drug effects; D005796:Genes; D005798:Genes, Bacterial; D005809:Genes, Regulator / Q000187:drug effects*; D006602:Hexosyltransferases / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D012689:Sequence Homology, Nucleic Acid; D013393:Sucrase / Q000096:biosynthesis / Q000235:genetics*; D013395:Sucrose / Q000494:pharmacology*; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
chemical_list: D013395:Sucrose; D006602:Hexosyltransferases; C021513:levansucrase; D001616:beta-Galactosidase; D013393:Sucrase