Emissive Synthetic Cofactors: A Highly Responsive NAD(+) Analogue Reveals Biomolecular Recognition Features

Feldmann, Jonas; Li, Yao und Tor, Yitzhak (2019): Emissive Synthetic Cofactors: A Highly Responsive NAD(+) Analogue Reveals Biomolecular Recognition Features. In: Chemistry-A European Journal, Bd. 25, Nr. 17: S. 4379-4389

Abstract

Apart from its vital function as a redox cofactor, nicotinamide adenine dinucleotide (NAD(+)) has emerged as a crucial substrate for NAD(+)-consuming enzymes, including poly(ADP-ribosyl)transferase 1 (PARP1) and CD38/CD157. Their association with severe diseases, such as cancer, Alzheimer's disease, and depressions, necessitates the development of new analytical tools based on traceable NAD(+) surrogates. Here, the synthesis, photophysics and biochemical utilization of an emissive, thieno[3,4-d]pyrimidine-based NAD(+) surrogate, termed N(th)AD(+), are described. Its preparation was accomplished by enzymatic conversion of synthetic (th)ATP by nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1). The new NAD(+) analogue possesses useful photophysical features including redshifted absorption and emission maxima as well as a relatively high quantum yield. Serving as a versatile substrate, N(th)AD(+) was reduced by alcohol dehydrogenase (ADH) to N(th)ADH and afforded (th)ADP-ribose ((th)ADPr) upon hydrolysis by NAD(+)-nucleosidase (NADase). Furthermore, N(th)AD(+) was engaged in cholera toxin A (CTA)-catalyzed mono((th)ADP-ribosyl)ation, but was found incapable in promoting PARP1-mediated poly((th)ADP-ribosyl)ation. Due to its high photophysical responsiveness, N(th)AD(+) is suited for spectroscopic real-time monitoring. Intriguingly, and as an N7-lacking NAD(+) surrogate, the thieno-based cofactor showed reduced compatibility (i.e., functional similarity compared to native NAD(+)) relative to its isothiazolo-based analogue. The distinct tolerance, displayed by diverse NAD(+) producing and consuming enzymes, suggests unique biological recognition features and dependency on the purine N7 moiety, which is found to be of importance, if not essential, for PARP1-mediated reactions.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 0947-6539
• Sprache: Englisch