Chinnadurai G, McCorquodale D J
Proc Natl Acad Sci U S A. 1973 Dec;70(12):3502-5. doi: 10.1073/pnas.70.12.3502.
Amber mutants of bacteriophage T5 defective in gene D15, which codes for a 5'-exonuclease, do not express late genes. Electrophoretic separation in sodium dodecyl sulfate-polyacrylamide gels of the proteins induced by this mutant in nonpermissive Escherichia coli show a virtual absence of late proteins. Synthesis of lysozyme and serum-blocking power is very low whereas the extent of synthesis of an early enzyme, deoxyribonucleoside monophosphokinase, is similar to that in wild-type infections. It is proposed that one requirement for the expression of late T5 genes is the introduction of gaps or nicks in the T5 DNA so that late transcription can occur.
噬菌体T5的琥珀突变体在编码5'-核酸外切酶的D15基因上存在缺陷，这些突变体不表达晚期基因。在非允许型大肠杆菌中，由该突变体诱导产生的蛋白质在十二烷基硫酸钠-聚丙烯酰胺凝胶中的电泳分离显示几乎没有晚期蛋白质。溶菌酶的合成和血清阻断能力非常低，而早期酶脱氧核糖核苷单磷酸激酶的合成程度与野生型感染时相似。有人提出，T5晚期基因表达的一个条件是在T5 DNA中引入缺口或切口，以便能够进行晚期转录。
