lactase


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Related to lactase: lactase deficiency, lactate

lactase

 [lak´tās]
β-d-galactosidase; an enzyme in the intestinal mucosa that hydrolyzes lactose, producing glucose and galactose.
lactase deficiency a deficiency of intestinal lactase, which causes abdominal distention and cramping and often diarrhea when milk is drunk. The condition is usually hereditary with an onset between infancy and early adulthood, and is more common in Blacks, American Indians, and East Asians (70 to 90 per cent) than in Whites (10 to 15 per cent). It may also occur secondary to massive small bowel resection or to diseases involving the mucosa, such as celiac disease, Crohn's disease, tropical sprue, and ulcerative colitis.

β-d-ga·lac·to·sid·ase

(gă-lak'tō-sīd'ās),
An enzyme that catalyzes the hydrolysis of lactose into d-glucose and d-galactose, as well as the hydrolysis of other β-d-galactosides; it also catalyzes galactotransferase reactions; a deficiency of β-d-galactosidase leads to problems in the intestinal digestion of lactose; used in the production of milk products for adults who lack the intestinal enzyme; a defect of one isozyme of β-d-galactosidase is associated with Morquio syndrome type B. Compare: lactase persistence, lactase restriction.
Synonym(s): lactase

lactase

/lac·tase/ (lak´tās) a β-galactosidase occurring in the brush border membrane of the intestinal mucosa that catalyzes the cleavage of lactose to galactose and glucose; it is part of the β-glycosidase enzyme complex.

lactase

(lăk′tās′)
n.
An enzyme occurring in certain yeasts and in the intestinal juices of mammals and catalyzing the hydrolysis of lactose into glucose and galactose.

lactase

[lak′tās]
Etymology: L, lac + Fr, diastase, enzyme
an enzyme that catalyzes the hydrolysis of lactose to glucose and galactose. Lactase is concentrated in the kidney, liver, and intestinal mucosa. Also called beta-galactosidase.

GLB1

A gene on chromosome 3p21.33 that encodes beta-galactosidase-1, a lysosomal enzyme that hydrolyses the terminal beta-galactose from gangliosides and other glycoconjugates.

Molecular biology
GLB1 mutations cause GM1-gangliosidosis and mucopolysaccharidosis IV (Morquio B syndrome).

β

Abbreviation for beta.

be·ta

(β) (bā'tă)
1. Second letter of the Greek alphabet.
2. chemistry Denotes the second in a series, the second carbon from a functional (e.g., carboxylic) group, or the direction of a chemical bond toward the viewer. For terms with the prefix β, see the specific term.

lactase

An enzyme that brings about the HYDROLYSIS of LACTOSE to glucose (dextrose) and galactose. Beta-galactosidase.

lactase

an enzyme that splits the disaccharide LACTOSE into galactose and glucose, secreted as part of the intestinal juice by glands in the SMALL INTESTINE wall. Lactase is also produced in ENZYME INDUCTION by bacteria (see OPERON MODEL).

lactase

d-galactosidase; an enzyme in the intestinal mucosa that hydrolyzes lactose, producing glucose and galactose.

lactase deficiency
a deficiency of intestinal lactase, which causes abdominal distention and cramping and often diarrhea when milk is drunk.
References in periodicals archive ?
Another option is replacing the lactase enzyme, but current lactase formulations work only in the acidic environment of the stomach.
Studies in infants recovering from enteritis have shown that ingestion of cow's milk protein can cause a marked reduction in lactase, sucrase, and maltase activity (isomaltase activity was not measured), accompanied by histologic changes in jejunal mucosa.
Arylsulfatase is an impurity found in lactase that converts components naturally present in milk to cause off-Flavour in lactose-free dairy products, resulting in a limited shelf life.
oryzae lactase, Holsinger dry-blended the enzyme into a nonfat milk powder made with vegetable oil to yield 2-percent-fat milk when mixed with water.
lactase insufficiency) as well as pharmacological reactions to food components.
Yogurt is another good choice since those with live cultures contain microorganisms that produce lactase, aiding digestion.
Normally, a chemical called lactase (LAK-tase) breaks down milk sugar in the small intestine.
Acquired milk intolerance in the adult caused by lactose malabsorption due to a selective deficiency of intestinal lactase activity.
Lactase (such as Lactaid, Dairy Ease, and Lactrase) helps digest foods that contain lactose.
In people with lactose intolerance, the small intestines don't produce enough of the lactase enzyme, which causes the lactose in their intestines to stay unbroken.
Many studies reviewed by the panel did not verify if gastrointestinal symptoms resulted from lactose malabsorption (which may or may not be symptomatic) in people who have lost most or all lactase expression in their small intestine These so-called lactase nonpersisters form the majority of all people worldwide.
In order to turn lactose into energy, our bodies need an enzyme called lactase.