Title: Substrate-specifying determinants of the nucleotide pyrophosphatases/phosphodiesterases NPP1 and NPP2
Authors: Cimpean, Anisoara ×
Stefan, Cristiana
Gijsbers, Rik
Stalmans, Willy
Bollen, Mathieu #
Issue Date: Jun-2004
Publisher: Published by Portland Press on behalf of the Biochemical Society
Series Title: Biochemical Journal vol:381 issue:Pt 1 pages:71-7
Abstract: The nucleotide pyrophosphatases/phosphodiesterases NPP1 and NPP2/autotaxin are structurally related eukaryotic ecto-enzymes, but display a very different substrate specificity. NPP1 releases nucleoside 5'-monophosphates from various nucleotides, whereas NPP2 mainly functions as a lysophospholipase D. We have used a domain-swapping approach to map substrate-specifying determinants of NPP1 and NPP2. The catalytic domain of NPP1 fused to the N- and C-terminal domains of NPP2 was hyperactive as a nucleotide phosphodiesterase, but did not show any lysophospholipase D activity. In contrast, chimaeras of the catalytic domain of NPP2 and the N- and/or C-terminal domains of NPP1 were completely inactive. These data indicate that the catalytic domain as well as both extremities of NPP2 contain lysophospholipid-specifying sequences. Within the catalytic domain of NPP1 and NPP2, we have mapped residues close to the catalytic site that determine the activities towards nucleotides and lysophospholipids. We also show that the conserved Gly/Phe-Xaa-Gly-Xaa-Xaa-Gly (G/FXGXXG) motif near the catalytic site is required for metal binding, but is not involved in substrate-specification. Our data suggest that the distinct activities of NPP1 and NPP2 stem from multiple differences throughout the polypeptide chain.
ISSN: 0264-6021
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Biochemistry Section (Medicine) (-)
Molecular Virology and Gene Therapy
Department of Cellular and Molecular Medicine - miscellaneous
Laboratory of Biosignaling & Therapeutics
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science