| Abstrakt: |
Kahn, PhyllisL. (Princeton University, Princeton, N.J.), and Donald R. Helinski. Relationship between colicinogenic factors E1and V and an F factor in Escherichia coli. J. Bacteriol. 88:1573–1579. 1964.—Colicinogenic factors are the genetic determinants for colicin production in enteric bacteria. An examination of the relationship of two colicinogenic factors, colE1and colV, to the F factor of fertility in Escherichia colirevealed that the colE1factor does not have the properties of a fertility factor, whereas the colVfactor appears to possess a genetic determinant of fertility (Fv). Cells containing colE1alone do not recombine with F−strains, whereas V+Fv+strains can recombine, but at a lower frequency for certain markers than cells containing the F factor from E. coli. Strains possessing the colVfactor can transfer the V+and Fv+properties to an F−recipient, whereas strains harboring colE1alone are not able to transfer this factor. When a V+Fv+E1+strain is used as a donor, recipients show Fv+sexuality characteristics only if they also acquire the ability to produce colicin V. The colVfactor is transferred at lower efficiency to F+than to F−strains, whereas the transfer of colE1is equally efficient to both. In addition, the V+Fv+F+colonies isolated segregate V+Fv+F−and V−Fv−F+cells at high frequency, indicating an incompatibility between the colVand F factors. Finally, under the conditions employed, acridine orange does not remove the colE1factor, but will remove the colVfactor from colicinogenic cells. In every case tested, the V+and Fv+characteristics are removed simultaneously by the acridine orange treatment. |
