title: Metabolism of cyclic ADP-ribose: Zinc is an endogenous modulator of the cyclase/NAD glycohydrolase ratio of a CD38-like enzyme from human seminal fluid.
abstract: CD38, a bifunctional enzyme capable of both synthesis and hydrolysis of the second messenger cyclic ADP-ribose (cADPR). Using the natural substrate of the enzyme, NAD+, the ratio of ADP-ribosyl cyclase/NAD glycohydrolase of CD38 is about 1/100. Here we describe that human seminal fluid contain a soluble CD38 like enzyme with an apparent M.W. of 49 kDa. When purified this enzyme has a cyclase/NAD glycohydrolase ratio of about 1/120. However, the in situ cyclase/NAD glycohydrolase ratio measured in seminal plasma approaches 1/1. We also found that physiological concentrations of zinc present in the seminal fluid, in the range of 0.6 to 4 mM, are responsible for the modulation of the cyclase/NAD glycohydrolase ratio. This new information indicates that the cyclase/NAD glycohydrolase ratio can be modified in vivo.
authors.affiliation: Departments of Anesthesiology and Internal Medicine, Mayo Clinic and Foundation, Rochester, MN 55905, USA.
authors.forename: Weronika
authors.initials: W
authors.lastname: Zielinska
authors.forename: Hosana
authors.initials: H
authors.lastname: Barata
authors.forename: Eduardo N
authors.initials: EN
authors.lastname: Chini
mesh_terms: D036541:ADP-ribosyl Cyclase / Q000302:isolation & purification / Q000378:metabolism*; D051997:ADP-ribosyl Cyclase 1; D000328:Adult; D000818:Animals; D015703:Antigens, CD / Q000302:isolation & purification / Q000378:metabolism*; D001681:Biological Assay; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D036563:Cyclic ADP-Ribose / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins; D009244:NAD+ Nucleosidase / Q000378:metabolism*; D012617:Sea Urchins; D012661:Semen / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology*; D015032:Zinc / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D015703:Antigens, CD; D008562:Membrane Glycoproteins; D036563:Cyclic ADP-Ribose; D004492:Edetic Acid; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D009244:NAD+ Nucleosidase; D051997:ADP-ribosyl Cyclase 1; D015032:Zinc