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TSG-6 transfers proteins between glycosaminoglycans via a Ser28-mediated covalent catalytic mechanism.

ABSTRACT: Studies of the interaction between Bikunin proteins, tumor necrosis factor-stimulated gene-6 protein (TSG-6), and glycosaminoglycans have revealed a unique catalytic activity where TSG-6/heavy chain 2 transfer heavy chain subunits between glycosaminoglycan chains. The activity is mediated by TSG-6/heavy chain 2 and involves a transient SDS stable interaction between TSG-6 and the heavy chain to be transferred. The focus of this study was to characterize the molecular structure of this cross-link to gain further insight into the catalytic mechanism. The result showed that the C-terminal Asp residue of the heavy chains forms an ester bond to Ser(28) beta-carbon of TSG-6 suggesting that this residue plays a role during catalysis.

SUBMITTER: Sanggaard KW

PROVIDER: S-EPMC2662217 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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TSG-6 transfers proteins between glycosaminoglycans via a Ser28-mediated covalent catalytic mechanism.

Sanggaard Kristian W KW Sonne-Schmidt Carsten S CS Krogager Toke P TP Kristensen Torsten T Wisniewski Hans-Georg HG Thøgersen Ida B IB Enghild Jan J JJ

The Journal of biological chemistry 20080926 49

Studies of the interaction between Bikunin proteins, tumor necrosis factor-stimulated gene-6 protein (TSG-6), and glycosaminoglycans have revealed a unique catalytic activity where TSG-6/heavy chain 2 transfer heavy chain subunits between glycosaminoglycan chains. The activity is mediated by TSG-6/heavy chain 2 and involves a transient SDS stable interaction between TSG-6 and the heavy chain to be transferred. The focus of this study was to characterize the molecular structure of this cross-link ...[more]

PMID: 18820257

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