Isolation and Partial Characterization of Structural Components of the Walls of Alkalophilic Bacillus Strain C-125

Abstract

After trichloroacetic acid extraction of the walls of alkalophilic Bacillus sp. strain C-125 grown at an alkaline or a neutral pH, two acidic structural polymer fractions were isolated by ionexchange chromatography and gel chromatography. One was a teichuronic acid fraction containing N-acetyl-d-fucosamine, glucuronic acid and galacturonic acid in a molar ratio of 1: 1: 1. This teichuronic acid amounted to 390 μg per mg peptidoglycan in the walls of the bacterium grown at an alkaline pH or 80 μg per mg at a neutral pH. The molecular weight of the teichuronic acid from the cells grown at an alkaline pH was 70000 compared to a molecular weight of 48000 at a neutral pH as estimated by gel chromatography. The other fraction contained glucuronic acid and l-glutamic acid in a molar ratio of 1: 5. This fraction was either a copolymer of both the acids or a mixture of polyglucuronate and polyglutamate. This fraction amounted to 560 μg per mg peptidoglycan in the walls of the bacterium grown at an alkaline pH or 240 μg per mg at a neutral pH. The molecular weight of the fraction from both the wall preparations was about 19000.