Role of adenosine kinase in Saccharomyces cerevisiae: identification of the ADO I gene and study of the mutant phenotypes

Sequencing of the Saccharomyces cerevisiae genome revealed an open reading frame (YJR105w) encoding a putative protein highly similar to adenosine kin ases from other species. Disruption of this gene (renamed ADO1) affected ut ilization of S-adenosyl methionine (AdoMet) as a purine source and resulted in a severe reduction of adenosine kinase activity in crude extracts, Furt hermore, knock-out of ADO1 led to adenosine excretion in the medium and res istance to the toxic adenosine analogue cordycepin, From these data me conc lude that ADO1 encodes yeast adenosine kinase, We also show that ADO1 does not play a major role in adenine utilization in yeast and we propose that t he physiological role of adenosine kinase in S, cerevisiae could primarily be to recycle adenosine produced by the methyl cycle, Copyright (C) 2001 Jo hn Wiley & Sons, Ltd.