title: Isolation and structural analysis of the phospho-beta-galactosidase gene from Streptococcus lactis Z268.
abstract: A 4.4-kb XhoI fragment of Streptococcus lactis L13 (Z268) lactose plasmid pUCL13, containing the beta-D-phosphogalactoside galactohydrolase (P-beta Gal; EC 3.2.1.85)-coding gene has been cloned in Escherichia coli. Further subcloning and deletion of this fragment allowed localization of the P-beta Gal-coding gene (pbg) on a minimal 1.8-kb segment. Expression of P-beta Gal activity was constitutive and was not regulated by glucose in E. coli. The presence of P-beta Gal activity was correlated with the production of a 56.5-kDa protein in E. coli minicells. The nucleotide sequence of the cloned gene was determined and potential promoter structural elements were identified.
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D004790:Enzyme Induction / Q000187:drug effects; D005696:Galactosidases / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D005947:Glucose / Q000494:pharmacology; D006026:Glycoside Hydrolases; D013294:Lactococcus lactis / Q000201:enzymology / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D001616:beta-Galactosidase / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D005696:Galactosidases; D006026:Glycoside Hydrolases; D001616:beta-Galactosidase; C022361:6-phospho-beta-galactosidase; D005947:Glucose