Polysaccharides Produced by Cystobactev, Archangium, Sorangium and Stigmatella Species

Abstract

Exopolysaccharides and lipopolysaccharides were prepared from a number of myxobacterial strains representing the more complex types. The exopolysaccharides were isolated from fruiting bodies and from liquid and solid cultures. The polysaccharides secreted by the bacillary forms in solid or liquid media closely resembled the material obtained from fruiting bodies, the monosaccharides present being in the same approximate molar ratios. Many of the sugars present in the exopolysaccharides were also detected in the lipopolysaccharides, suggesting an economic use of sugar nucleotide synthetic systems. Several, but not all, lipopolysaccharides contained material resembling 3-0-methylxylose in its chromatographic mobility. In addition, a faster-moving spot, as yet unidentified, was noted in some hydrolysates. The commonest monosaccharide components of the lipopolysaccharide were rhamnose, mannose, glucose and galactose. Small quantities of amino sugars, particularly glucosamine and galactosamine, were also detected.

Biochemical and structural analyses of the extracellular matrix fibrils of Myxococcus xanthus

“…4D was seen to move freely at the end distal to the cell. It (36). Further analysis indicated that the isolated fibrils contained a surprisingly large amount of protein, composing up to 45% of the fibrils.…”

“…This differentiation reflects a fundamental difference in the extracellular polysaccharides produced by members of each suborder. Since analysis of the composition of polysaccharides and lipopolysaccharides from members of the two groups does not indicate significant compositional differences (36), the difference in Congo red binding ability is probably due to the structure of the polysaccharides (diazo dyes such as Congo red bind most avidly to carbohydrates containing atl-4 linkages [23]). …”

Extracellular fibrils and contact-mediated cell interactions in Myxococcus xanthus

“…Sutherland and Thomson isolated exopolysaccharide from several genera of myxobacteria as an acetone-precipitable fraction released from intact cells by shear forces (33). Exopolysaccharide from several species of the genus Myxococcus constitutes 5 to 10% of the dry weight of the starting material and is predominantly composed of carbohydrates (neutral and amino sugars) (32). While it seems likely that the 30-nm extracellular fibrils that have been isolated from M. xanthus comprise at least part of the extracellular matrix, complete compositional analysis has yet to be done.…”

Frozen motion of gliding bacteria outlines inherent features of the motility apparatus

“…Several models have been proposed which offer diverse mechanomacromolecular and physico-chemical solutions of how bacterial gliding motility is established (Burchard, 1981(Burchard, , 1984Castenholz, 1982 ;Pate, 1988 ;Dworkin, 1996 ;Spormann, 1999). From the literature, it can be learned that gliding motility is a rather complex phenomenon, based on and influenced by an intrinsic apparatus responsible for mechanical work (Burchard et al, 1977 ;Pate & Chang, 1979 ;Lu$ nsdorf & Reichenbach, 1989), motility-supporting extracellular slime (Humphrey et al, 1979 ;Sutherland & Thomson, 1975 ;Sutherland, 1979 ;Gorski et al, 1993), components of the outer membrane (Gorski et al, 1992 ;Abbanat et al, 1986) and surface active compounds (Keller et al, 1983).…”