Structure of human semicarbazide-sensitive amine oxidase/vascular adhesion protein-1.Jakobsson, E., Nilsson, J., Ogg, D., Kleywegt, G.J.
(2005) Acta Crystallogr. D Biol. Crystallogr. 61: 1550-1562
- PubMed: 16239734
- DOI: 10.1107/S0907444905028805
- Primary Citation of Related Structures:
- PubMed Abstract:
Semicarbazide-sensitive amine oxidase (SSAO) belongs to a ubiquitous family of copper-containing amine oxidases (CuAOs). SSAO is also known as vascular adhesion protein-1 (VAP-1) and has been identified as one of the adhesion molecules involved in th ...
Semicarbazide-sensitive amine oxidase (SSAO) belongs to a ubiquitous family of copper-containing amine oxidases (CuAOs). SSAO is also known as vascular adhesion protein-1 (VAP-1) and has been identified as one of the adhesion molecules involved in the leukocyte-extravasation process. The structure of a truncated soluble form of human SSAO has been solved and refined to 2.5 A. As expected, SSAO is a homodimer with a fold typical of the CuAO family. The topaquinone (TPQ) cofactor and a copper ion characteristic of CuAOs are present in the active site, with the TPQ in the active ;off-copper' conformation. The structure reveals that a leucine residue (Leu469) located adjacent to the active site could function as a gate controlling its accessibility. An RGD motif is displayed on the surface, where it could be involved in integrin binding and possibly play a role in the shedding of SSAO from the membrane. Carbohydrate moieties are observed at five of six potential N-glycosylation sites. Carbohydrates attached to Asn232 flank the active-site entrance and might influence substrate specificity. The structure of an adduct of SSAO and the irreversible inhibitor 2-hydrazinopyridine has been solved and refined to 2.9 A resolution. Together, these structures will aid efforts to identify natural substrates, provide valuable information for the design of specific inhibitors and direct further studies.
Department of Cell and Molecular Biology, Uppsala University, Biomedical Centre, Box 596, SE-751 24 Uppsala, Sweden.