Bacterial strains, phages, and plasmids. The bacterial strains, phages, and plasmids used in this investigation are listed in Table 1. The bacterial strains were E. coli K-12 derivatives.Culture media. The media used for growth were identical to those described by Miller (26). The synthetic medium used was M63 medium (pH 7.2) (44) or M9 medium (pH 7.2) (26) and contained either glucose (5 g/liter), glycerol (5 g/liter), glucuronate (2.5 g/liter), galacturonate (2.5 g/liter), tagaturonate (2.5 g/liter), or fructuronate (2.5 g/liter); aldohexuronate-containing MacConkey media (Difco Laboratories) contained 15 mg of glucuronate or galacturonate per ml. When needed, ampicillin, chloramphenicol, and kanamycin were used at final concentrations of 25 jig/ml, and 973 on August 5, 2020 by guest