Gel filtration chromatography of exopolysaccharides (EPS) produced by the R. leguminosarum bv. trifolii 24.2 wild type and the rosR mutants (Rt2440 and Rt2441). (A) EPS was fractionated on a Bio-Gel A-5m column, as described in the Methods. The retention times of molecular mass markers: dextran blue (2 MDa), dextran T250 (250 kDa), and dextran T10 (10 kDa) are indicated by arrows. (B) A 500 MHz 1H-NMR spectrometry analysis of the R. leguminosarum wild type and the rosR mutant (Rt2440). (C) The glycosyl components and non-carbohydrate substituents of EPS from the wild type and the mutant Rt2440. (D) Silver-stained Tricine SDS-PAGE profiles of LPS from the wild type and the rosR mutants. LPSs (2 μg) were loaded in 2 μl sample buffer. Lanes: 1- Salmonella enterica sv. Typhimurium (Sigma), 2- wild type Rt24.2, 3- Rt2440, 4- Rt2441. LPS I, high-molecular-weight LPS; LPS II, low-molecular-weight LPS. (E) The glycosyl composition of polysaccharides lacking lipid A released from LPS by mild acid hydrolysis from the wild type and the rosR mutant (Rt2440).