ISOLATION AND IDENTIFICATION OF POLY(3-HYDROXYVALERATE)-DEGRADING STRAINS OF PSEUDOMONAS-LEMOIGNEI

By using selective enrichment of polyhydroxyalkanoate-degrading bacter ia and poly(3-hydroxyvalerate)-containing granules from Chromobacteriu m violaceum as the carbon source, 10 new Pseudomonas lemoignei strains were isolated; these strains were able to degrade poly(3-hydroxyvaler ate), as well as poly(3-hydroxybutyrate), in vitro. The new isolates w ere characterized and identified by comparing them with P. lemoignei L MG 2207(T) (T = type strain). Like P. lemoignei LMG 2207(T) cells, the cells of the 10 new isolates contained mainly hexadecenoic, hexadecan oic, octadecenoic, and dodecanoic acids, as well as hydroxylated fatty acids, and exhibited respiration in the presence of methylpyruvate, 3 -hydroxybutyrate, and 4-hydroxybutyrate, but not in the presence of th e 92 other carbon sources included in Biolog GN microplates. The prote in patterns of the new isolates were almost identical to each other an d very similar to the protein pattern of P. lemoignei LMG 2207(T). Som e of the new isolates, but not P. lemoignei LMG 2207(T), contained meg aplasmids that were about 200 kbp long. The 16S ribosomal DNA genes of strain A62, a representative of the 10 new isolates, and of P. lemoig nei LMG 2207(T) exhibited more than 0.99 sequence similarity. The DNA- DNA reassociation value for two representative strains was 100%, and t he levels of DNA-DNA reassociation between these strains and the type strain were 60 and 61%. The taxonomy of P. lemoignei is briefly discus sed.