furthermore , the mutant strains dap 1 , devoid of adenine phosphoribosyltransferase activity , and pur 1 , devoid of guanine phosphoribosyltransferase activity have a lowered uptake rate of adenine and guanine respectively , along with an increased apparent km value for these purines in comparison to the wild-type 972h .
C0001407
adenine
C0034140
purines