Polysaccharide degradation by aquatic Cytophaga populations in a eutrophic lake and in mixed cultures

Summary

Bacteria of the Cytophaga-Flavobacterium group were found regularly as polysaccharide degraders in the pelagial and littoral of a eutrophic lake. In mixed cultures with polysaccharide containing natural substrates (autoclaved algae) Cytophaga populations developed in succession after not identified populations of cocci and motile rods at 20°C. In these experiments amylase and xylanase were produced by all populations, whereas pectinase and cellulase were detected only in presence of Cytophaga. At 5°C Cytophaga populations dominated from the beginning of the culture and all tested polysaccharidases were produced. The ecological interpretation of the results is discussed.