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Zinc-dependent dimers observed in crystals of human endostatin.

ABSTRACT: The crystal structure of human endostatin reveals a zinc-binding site. Atomic absorption spectroscopy indicates that zinc is a constituent of both human and murine endostatin in solution. The human endostatin zinc site is formed by three histidines at the N terminus, residues 1, 3, and, 11, and an aspartic acid at residue 76. The N-terminal loop ordered around the zinc makes a dimeric contact in human endostatin crystals. The location of the zinc site at the amino terminus, immediately adjacent to the precursor cleavage site, suggests the possibility that the zinc may be involved in activation of the antiangiogenic activity following cleavage from the inactive collagen XVIII precursor or in the cleavage process itself.

SUBMITTER: Ding YH

PROVIDER: S-EPMC27913 | biostudies-literature | 1998 Sep

REPOSITORIES: biostudies-literature

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Zinc-dependent dimers observed in crystals of human endostatin.

Ding Y H YH Javaherian K K Lo K M KM Chopra R R Boehm T T Lanciotti J J Harris B A BA Li Y Y Shapiro R R Hohenester E E Timpl R R Folkman J J Wiley D C DC

Proceedings of the National Academy of Sciences of the United States of America 19980901 18

The crystal structure of human endostatin reveals a zinc-binding site. Atomic absorption spectroscopy indicates that zinc is a constituent of both human and murine endostatin in solution. The human endostatin zinc site is formed by three histidines at the N terminus, residues 1, 3, and, 11, and an aspartic acid at residue 76. The N-terminal loop ordered around the zinc makes a dimeric contact in human endostatin crystals. The location of the zinc site at the amino terminus, immediately adjacent ...[more]

PMID: 9724722

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