Unusual enzymatic hydrolysis of NAD by solubilized form of NAD(+) glycohydrolase.
Chemical & pharmaceutical bulletin
confidence
Key findings
Solubilized NADase cleaves NAD at the adenosine P-O bond yielding novel products, unlike membrane-bound enzyme; enzymatic mechanism study.
View source on PubMed (PMID 12045341) ↗
- Sample size
- N/A
- Population
- In vitro enzymatic assay (porcine brain NAD+ glycohydrolase)
- Dosing
- N/A
- Duration
- N/A
- Route
- in vitro
- Blinding
- not_reported
- Controls
- none
- Drug class
- coenzyme
Full abstract
Using solubilized form (sNADase) of membrane-bound porcine brain NAD(+) glycohydrolase (pNADase), the NADase-catalyzed hydrolysis and transglycosidation reactions of NAD (1) were examined. Unexpectedly, products in the reactions were found to be nicotinamide (5'-O-diphosphono)-beta-D-ribofuranoside (4) and adenosine (5). Adenosine 5'-diphosphate (ADP)-ribose (2) and nicotinamide (3) as well as a transglycosylated product, which are formed in a usual NAD/pNADase reaction system, were scarcely produced in the NAD/sNADase system. Setting aside the mechanical aspects of this unusual cleaving, it is quite interesting that the sNADase-catalyzed hydrolytic reaction of NAD resulted in the selective cleavage of the P-O bond of the adenosine side without the appreciable hydrolysis of the labile quaternary nicotinamide-ribose pyridinium linkage.