MUTATIONAL ALTERATION OF BACILLUS-SUBTILIS DNA POLYMERASE III TO HYDROXY-PHENYLAZOPYRIMIDINE RESISTANCE - POLYMERASE III IS NECESSARY FOR DNA-REPLICATION
MUTATIONAL ALTERATION OF BACILLUS-SUBTILIS DNA POLYMERASE III TO HYDROXY-PHENYLAZOPYRIMIDINE RESISTANCE - POLYMERASE III IS NECESSARY FOR DNA-REPLICATION
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DOI：
10.1016/0006-291x(73)90521-4
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发表时间：
1973-01-01
影响因子：
3.1
通讯作者：
LOW, RL
中科院分区：
文献类型：
--
作者：
COZZARELLI, NR;LOW, RL
从枯草芽孢杆菌中分离到一株对两种羟基苯基偶氮嘧啶类药物有抗性的自发突变株。该突变体的DNA聚合酶III对这些药物的抑制具有抗性。6-（p-hydroxyphenylazo）-uracil（HPUra）的Ki为20 μM，比野生型酶的Ki高约40倍。突变型和野生型聚合酶在纯化过程中的行为相似，对N-乙基马来酰亚胺和0.1 M KCl敏感，对dGTP（0.5 μM）的Km相同。这两种酶的HPUra抑制通过dGTP竞争性减弱。我们的结论是，聚合酶III是目标羟基苯基偶氮嘧啶在体内，由于药物特异性抑制复制DNA合成，聚合酶III是必要的DNA复制。
A spontaneous mutant of Bacillus subtilis resistant to killing by two hydroxyphenylazopyrimidines has been isolated. The DNA polymerase III of this mutant is resistant to inhibition by these drugs. The K i for 6-(p-hydroxyphenylazo)-uracil (HPUra) is 20 μM, about 40 times higher than the K i of the wild-type enzyme. The mutant and wild-type polymerases behave similarly during purification, are sensitive to N-ethylmaleimide and to 0.1 M KCl, and have the same K m for dGTP (0.5 μM). The HPUra inhibition of both enzymes is attenuated competitively by dGTP. We conclude that polymerase III is the target for hydroxyphenylazopyrimidines in vivo, and since the drugs specifically inhibit replicative DNA synthesis, polymerase III is necessary for DNA replication.