Isolation of specialized transducing bacteriophage lambda carrying genes of the L-arabinose operon of Escherichia coli B/r

Abstract

A heat-inducible lysis-defective phage lambda (AcI857S7) has been integrated at multiple sites within the L-arabinose region (araCOIBAD) of a strain of Escherichia coli K-12 deleted for the normal lambda attachment site (AattA). The lambda phage has become integrated with opposite orientations at two different loci within the araB gene and with the "normal" orientation (clockwise N-RAJ) at a single site in the araC gene. The burst size, spontaneous-curing frequencies, and number of prophage harbored by each of the ara secondary-site lysogens have been determined. From these secondary-site lysogens it has been possible to generate plaque-forming ara-transducing phage (Xpara) and defective ara-transducing phage (Adara), as well as defective leucine-transducing particles (Adleu). The construction and characterization of these Aara-transducing phage and their derivatives which carry genetically defined portions of the L-arabinose region are presented.

Isolation of specialized transducing bacteriophages carrying the structural genes of the hexuronate system in Escherichia coli K-12: exu region

“…Our results indicate that the ?gal-type transducing phages derived from HfrH 58 and Xdexu2 isolated by Schrenk's method both carry a different portion of the exuR gene. It appears that phage X can integrate in the exuR gene at two different locations as in the araB gene (3).…”

“…ASpi-(6) were isolated using fresh LFT lysates derived from HfrH 58, and 0.1 ml of the lysate, containing 10' plaque-forming units, was infected cells were poured onto tryptone plates. After overnight incubation at 370C, plaques of XSpiappeared and were isolated as described by Boulter and Lee (3).…”