A new function for a common fold: the crystal structure of quinolinic acid phosphoribosyltransferase.Eads, J.C., Ozturk, D., Wexler, T.B., Grubmeyer, C., Sacchettini, J.C.
(1997) Structure 5: 47-58
- PubMed: 9016724
- DOI: https://doi.org/10.1016/s0969-2126(97)00165-2
- Primary Citation of Related Structures:
- PubMed Abstract:
Quinolinic acid (QA) is a neurotoxin and has been shown to be present at high levels in the central nervous system of patients with certain diseases, such as AIDS and meningitis. The enzyme quinolinic acid phosphoribosyltransferase (QAPRTase) provides the only route for QA metabolism and is also an essential step in de novo NAD biosynthesis. QAPRTase catalyzes the synthesis of nicotinic acid mononucleotide (NAMN) from QA and 5-phosphoribosyl-1-pyrophosphate (PRPP). The structures of several phosphoribosyltransferases (PRTases) have been reported, and all have shown a similar fold of a five-strandard beta sheet surrounded by four alpha helices. A conserved sequence motif of 13 residues is common to these 'type I' PRTases but is not observed in the QAPRTase sequence, suggestive of a different fold for this enzyme.
Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA.