Lo K Y, Bessman M J
J Biol Chem. 1976 Apr 25;251(8):2480-6.
Upon infection of Escherichia coli with the temperature-sensitive bacteriophage T4 mutant, L141, at 43 degrees, DNA polymerase activity is induced, yet there is a marked decrease in DNA synthesis. Temperature shift experiments of infected cultures show dramatic changes in the rate of DNA synthesis, while the polymerase activity in extracts remains constant. Unlike most temperature-sensitive systems in which the lesion can be traced to an unstable enzyme, L141 provides a unique example in which the catalytic properties of the enzyme and the change in the nature of the template caused by the increased temperature combine to reduce the rate of DNA synthesis.
在43摄氏度用温度敏感型噬菌体T4突变体L141感染大肠杆菌时，会诱导DNA聚合酶活性，但DNA合成却显著减少。对受感染培养物进行的温度转换实验表明，DNA合成速率发生了显著变化，而提取物中的聚合酶活性保持不变。与大多数可将损伤追溯到不稳定酶的温度敏感系统不同，L141提供了一个独特的例子，其中酶的催化特性与温度升高导致的模板性质变化共同作用，降低了DNA合成速率。
