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

Weronika Zielinska, Hosana Barata, Eduardo N. Chini

Research output: Contribution to journalArticle

18 Scopus citations


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.

Original languageEnglish (US)
Pages (from-to)1781-1790
Number of pages10
JournalLife Sciences
Issue number14
StatePublished - Feb 20 2004



  • Endoplasmic reticulum
  • IP
  • Ryanodine channel
  • Zinc
  • cADPR

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Pharmacology, Toxicology and Pharmaceutics(all)

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