DISSIPOTROPHS IN THE MICROBIAL COMMUNITY

The term ''dissipotrophs'' is suggested for the bacteria that use simp le monomeric substrates resulting from hydrolyzed polymers or originat ing from other sources. The term ''dispersion microflora'' was earlier suggested for this trophic group of bacteria. Most dissipotrophs belo ng to prosthecate bacteria, which phylogenetically represent a single group, part of the a-subclass of the proteobacteria. Dissipotrophs are characterized by (a) the inability to utilize polymers, (b) a high af finity for substrates present at low concentrations, and (c) low maxim um specific growth rates. Dissipotrophs specifically consume a limited number of substrates, a point discussed in this paper. Dissipotrophs develop not only in habitats with a low organic substance content; the y may also be abundant in ecosystems receiving large quantities of deg radable organic substances if the metabolite concentration tends to de crease due to a high density of microorganisms. ''Dissipotrophic bacte ria'' can be a useful term in describing microbial communities.