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Crystal structure of the catalytic domain of human bile salt activated lipase.

ABSTRACT: Bile-salt activated lipase (BAL) is a pancreatic enzyme that digests a variety of lipids in the small intestine. A distinct property of BAL is its dependency on bile salts in hydrolyzing substrates of long acyl chains or bulky alcoholic motifs. A crystal structure of the catalytic domain of human BAL (residues 1-538) with two surface mutations (N186D and A298D), which were introduced in attempting to facilitate crystallization, has been determined at 2.3 A resolution. The crystal form belongs to space group P2(1)2(1)2(1) with one monomer per asymmetric unit, and the protein shows an alpha/beta hydrolase fold. In the absence of bound bile salt molecules, the protein possesses a preformed catalytic triad and a functional oxyanion hole. Several surface loops around the active site are mobile, including two loops potentially involved in substrate binding (residues 115-125 and 270-285).

SUBMITTER: Terzyan S

PROVIDER: S-EPMC2144702 | biostudies-other | 2000 Sep

REPOSITORIES: biostudies-other

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Crystal structure of the catalytic domain of human bile salt activated lipase.

Terzyan S S Wang C S CS Downs D D Hunter B B Zhang X C XC

Protein science : a publication of the Protein Society 20000901 9

Bile-salt activated lipase (BAL) is a pancreatic enzyme that digests a variety of lipids in the small intestine. A distinct property of BAL is its dependency on bile salts in hydrolyzing substrates of long acyl chains or bulky alcoholic motifs. A crystal structure of the catalytic domain of human BAL (residues 1-538) with two surface mutations (N186D and A298D), which were introduced in attempting to facilitate crystallization, has been determined at 2.3 A resolution. The crystal form belongs to ...[more]

PMID: 11045623

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Crystal Structure of Human Nocturnin Catalytic Domain.

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Two forms of human milk bile-salt-stimulated lipase.

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