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Inhibition of multiplication of an F-lac factor in HFR cells of Escherichia coli K-12

1962; Elsevier BV; Volume: 7; Issue: 5 Linguagem: Inglês

10.1016/0006-291x(62)90324-8

1090-2104

J. A. Scaife, Julian D. Gross,

RNA and protein synthesis mechanisms

The donor property in Escherichia coli K-12 is determined by the sex factor, F. The sex factor exists in the autonomous state in F+ donors and is transferred by them at a high frequency to F− (recipient) cells (Lederberg et al., 1952; Hayes, 1953). In Hfr donors F is integrated on the chromosome and behaves as a terminal marker transferred only rarely. It has been argued from these observations that Hfr cells do not harbour F in the autonomous state (Jacob et al., 1960). However recent studies suggest that Hfr cells, unlike F+, transfer little or no cytoplasmic material (Fisher, 1962). Fisher has therefore pointed out that, although undetected by transfer, autonomous F may exist in Hfr cells. By infecting genetically similar Hfr, F+ and F− strains with an F-lac factor (Jacob and Adelberg, 1959) and analysing the clones formed, we have been able to demonstrate that multiplication of the F-lac is inhibited in Hfr cells.