title: Properties of lactase produced by enteropathogenic Escherichia coli from diarrhoeic children.
abstract: The quantity of lactase produced by enteropathogenic Escherichia coli (EPEC) was significantly higher (P less than 0.01) than that produced by non-EPEC. The enzyme production was induced by lactose but repressed by glucose and galactose. The lactase from EPEC which was partially purified by ammonium sulphate precipitation and gel permeation chromatography had a molecular weight of 56 kD and apparent Km of approximately 2.78 mM for lactose. The lactase exhibited optimum activity at pH 7.0 at 40 degree C and was stimulated by Mg2+, Mn2+, Na+ and inhibited by Ba2+, Ca+, Cu2+, EDTA, iodo acetic acid (IAA) and Hg2+ and U2+ ions. The higher production of lactase by EPEC may be linked to its pathogenic role in childhood diarrhoea.
authors.affiliation: Department of Medical Microbiology and Parasitology, Faculty of Health Sciences, University of Ife, Nigeria.
authors.forename: O
authors.initials: O
authors.lastname: Olusanya
authors.forename: P O
authors.initials: PO
authors.lastname: Olutiola
mesh_terms: D002675:Child, Preschool; D003967:Diarrhea / Q000201:enzymology*; D004926:Escherichia coli / Q000201:enzymology / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000201:enzymology*; D005243:Feces / Q000382:microbiology; D005260:Female; D005696:Galactosidases / Q000096:biosynthesis*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009549:Nigeria; D001616:beta-Galactosidase / Q000096:biosynthesis* / Q000502:physiology
chemical_list: D005696:Galactosidases; D001616:beta-Galactosidase