we have recently reported the isolation of a class of mutants ( called thy- ) that is both resistant to arabinosyl cytosine and auxotrophic for thymidine . thy- mutants have a 5- to 10-fold elevated pool of dctp and are deficient in the synthesis of dttp as an apparent consequence of a single mutation in the gene for ribonucleoside-diphosphate reductase ( 2'-deoxyribonucleoside-diphosphate : oxidized-thioredoxin 2'-oxidoreductase , ec 1.17.4.1 ) .
C0040077
thymidine
C0011528
deoxyribonucleoside