As part of a systematic structural study of surface polysaccharides elaborated by Acetobacter mefhunolicus, we examined the capsular polysaccharide (CPS) and the O-side-chain of the lipopolysaccharide (LPS) from strain MB 135 (IMET 11402). Attention was focused on this strain because of its resistance against all known phages' of this species, and its opposition against chemical and physical trials of prophage induction'.
Isolation of the CPS and LPS from lyophilised bacteria was conducted by the phenol-water extraction method3. The components were separated by ultracentrifugation, and the LPS was purified by DNase and RNase digestion followed by repeated ultracentrifugation steps. The CPS was obtained by DEAE-Sephacel ion-exchange chromatography4 in the neutral effluent. The recoveries of the LPS and CPS were 2.2 and 15%, respectively.
Acid hydrolysis and identification of the products by sugar analyzer and by GLC as their derived alditol acetates afforded mannose as the only monosaccharide in the CPS, and as the predominant one in the LPS (Table I).
On the basis of the specific optical rotation, the configuration of mannose was determined to be D which was confirmed by calculation of the value for the CPS according to Klyne's rule' (Table II).
The 'H NMR spectrum of the CPS contained signals for five anomeric protons at 6 5.04 (J,,, 1.8 Hz), 5.24 U1,2 1.5 Hz), and 5.44 ppm (J1,Z 1.5 Hz) (1, 3, and 1 H, respectively) indicating the D-mannosyl residues to be cw-pyranoid7.