DNA-DELAY MUTANTS OF BACTERIOPHAGE-T4
DNA-DELAY MUTANTS OF BACTERIOPHAGE-T4
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DOI：
10.1128/jvi.14.4.860-871.1974
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发表时间：
1974-01-01
影响因子：
5.4
通讯作者：
BERNSTEIN, H
中科院分区：
文献类型：
--
作者：
MUFTI, S;BERNSTEIN, H
Mutants of phage T4 defective in genes 39, 52, 58-61, and 60 (the DNA delay or DD genes) are characterized by a delay in phage DNA synthesis during infection of a nonpermissiveEscherichia colihost. Amber (am) mutants defective in these genes yield burst sizes varying from 30 to 110 at 37 C inE. colilacking anamsuppressor. It was found that when DDammutants are grown on a non-permissive host at 25 C, rather than at 37 C, phage yield is reduced on the average 61-fold. At 25 C incorporation of labeled thymidine into phage DNA is also reduced to 3 to 10% of wild-type levels. Mutants defective in the DD genes were found to promote increased recombination as well as increased base substitution and addition-deletion mutation. These observations indicate that the products of the DD genes are necessary for normal DNA synthesis. The multiplication of the DDammutants on an Su−host at 37 C is about 50-fold inhibited if prior to infection the host cells were grown at 25 C. This suggests that a compensating host function allows multiplication of DDammutants at 37 C in the Su−host, and that this function is active in cells grown at 37 C prior to infection, but is inactive when the prior growth is at 25 C. Further results are described which suggest that the products of genes 52, 60, and 39 as well as a host product interact with each other.
