Isolation and characterization of lambda transducing bacteriophages for the su1+ (supD minus) amber suppressor of Escherichia coli

Abstract

Specialized lambda transducing phages for the sul + (supD-) amber suppresssor in Escherichia coli K-12 have been isolated, using a secondary site XcI857 lysogen in which we have shown the prophage to be closely linked to sul +. sul+ transducing particles were detected frequently, at 10-5 per plaque-forming unit, in lysates prepared from the secondary-site lysogens. High-frequency transducing lysates were obtained from several independently isolated sul + transductants and were analyzed by CsCl equilibrium density gradient centrifugation. The transducing phages are defective; marker rescue analysis indicates that the XN gene is not present. In XcI857ANdSu1+, a bio-type transducing phage, the genes specifying recombination and excision functions have been replaced by bacterial deoxyribonucleic acid. 120 on July 31, 2020 by guest http://jb.asm.org/ Downloaded from VOL. 122, 1975 sul+ TRANSDUCING BACTERIOPHAGES OF E. COLI 122 STEEGE AND LOW

Isolation of specialized lambda transducing bacteriophages for flagellar genes (fla) of Escherichia coli K-12

“…Isolation of specialized transducing phage lines carrying fla genes. In an initial step, we thought that an E. coli K-12 strain, KS899 (9,14,19), which had a XcI857 prophage integrated between the his genes and the region HI fla genes (17) in its chromosome, would be useful for the isolation of the region III fla-transducing phages ( Fig. 1).…”

“…Accordingly, we attempted to isolate Xfla phages from the heatinduced lysates of strain KS899 by the method described for the isolation of Xgalor Xbiotransducing phages (2). However, the attempt was unsuccessful, probably because the location of the prophage was too distant from the region m fla genes (9,19). Therefore, we devised a new method for isolating transducing phages that carry parts ofthe fla and hag genes from derivatives of strain KS899.…”

Isolation of a lambdadcys transducing bacteriophage and its use in determining the regulation of cysteine messenger ribonucleic acid synthesis in Escherichia coli K-12

“…Preparation and tests of HFT lysates. Cys+ transductants were tested for ability to form HFT lysates by the procedure of Steege and Low (25), except that chloroform was used to lyse the induced cells and hence glass plates were used for heat induction. The results were confirmed with the HFT lysate spot test method.…”

Temperature-inducible amber suppressor: construction of plasmids containing the Escherichia coli serU- (supD-) gene under control of the bacteriophage lambda pL promoter

“…This plasmid was maintained in strain K802. Both the rich and minimal media used for bacterial growth and phage lysate preparations have been described previously (34).…”