RELATIONSHIP BETWEEN COLICINOGENIC FACTORS E 1 AND V AND AN F FACTOR IN ESCHERICHIA COLI

Abstract

Kahn, Phyllis L. (Princeton University, Princeton, N.J.), and Donald R. Helinski . Relationship between colicinogenic factors E 1 and 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, colE 1 and colV , to the F factor of fertility in Escherichia coli revealed that the colE 1 factor does not have the properties of a fertility factor, whereas the colV factor appears to possess a genetic determinant of fertility (F v ). Cells containing colE 1 alone do not recombine with F − strains, whereas V + F v + strains can recombine, but at a lower frequency for certain markers than cells containing the F factor from E. coli . Strains possessing the colV factor can transfer the V + and F v + properties to an F − recipient, whereas strains harboring colE 1 alone are not able to transfer this factor. When a V + F v + E 1 + strain is used as a donor, recipients show F v + sexuality characteristics only if they also acquire the ability to produce colicin V. The colV factor is transferred at lower efficiency to F + than to F − strains, whereas the transfer of colE 1 is equally efficient to both. In addition, the V + F v + F + colonies isolated segregate V + F v + F − and V − F v − F + cells at high frequency, indicating an incompatibility between the colV and F factors. Finally, under the conditions employed, acridine orange does not remove the colE 1 factor, but will remove the colV factor from colicinogenic cells. In every case tested, the V + and F v + characteristics are removed simultaneously by the acridine orange treatment.