Physiological and phylogenetic diversity of bacteria growing on resin acids

Resin acids are tricyclic diterpenes which are synthesized by trees and are a major cause of toxicity of pulp mill effluents. Bacterial strains isolat ed from three different sources and which grow on resin acids were physiolo gically characterized. Eleven strains, represent-sting distinct groups, wer e further characterized physiologically and phylogenetically. The isolates had distinct specificities for use, as growth substrates, of the different resin acids tested. The isolates also used fatty acids bur were generally l imited in use of other diverse substrates tested. According to their 16S rD NA sequences, the representative isolates are related to members of the gen era, Sphingomonas, Zoogloea, Ralstonia, Burkholderia, Pseudomonas and Mycob acterium. Analysis of whore-cell fatty acid profiles generally supported th ese phylogenetic relationships. However, most of the isolated did not have high similarities to reference strains in the Microbial Identification Syst em database of fatty acid profiles or in the Biolog database of substrate o xidation patterns. Described species of Sphingomonas, Zoolgoea, Burkholderi a Pseudomonas, most closely related to the isolates we characterized, faile d to grow on, or degrade, resin acids. We propose recognition of Zoogloea r esiniphila sp. nov, Pseudomonas vancouverensis sp. nov., P. abietaniphila s p. nov. and P. multiresinivorans sp. nov.