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High-resolution structures of bacterially expressed soluble human CD59.

ABSTRACT: CD59 is a membrane-bound glycoprotein that protects host cells from lysis by inhibiting the terminal pathway of complement, preventing the formation and insertion of the membrane attack complex (MAC). Crystals of bacterially expressed and nonglycosylated recombinant soluble human CD59 have been obtained from three crystallization conditions, each of which gave rise to a distinct crystal form. Each crystal form led to a crystal structure at high resolution (1.15, 1.35 and 1.8 A). In one of these structures the electron-density map shows an as yet unidentified small molecule in the predicted C8/C9-binding site. The presence/absence of this ligand is linked to alternate conformations of the amino acids implicated in C8/C9 binding.

SUBMITTER: Leath KJ

PROVIDER: S-EPMC2335151 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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High-resolution structures of bacterially expressed soluble human CD59.

Leath Kirstin J KJ Johnson Steven S Roversi Pietro P Hughes Timothy R TR Smith Richard A G RA Mackenzie Lloyd L Morgan B Paul BP Lea Susan M SM

Acta crystallographica. Section F, Structural biology and crystallization communications 20070728 Pt 8

CD59 is a membrane-bound glycoprotein that protects host cells from lysis by inhibiting the terminal pathway of complement, preventing the formation and insertion of the membrane attack complex (MAC). Crystals of bacterially expressed and nonglycosylated recombinant soluble human CD59 have been obtained from three crystallization conditions, each of which gave rise to a distinct crystal form. Each crystal form led to a crystal structure at high resolution (1.15, 1.35 and 1.8 A). In one of these ...[more]

PMID: 17671359

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