POLYAMINE DISTRIBUTION AMONG AUTHENTIC PSEUDOMONADS AND AZOTOBACTERACEAE

Polyamine patterning of 176 bacterial strains, of which 158 either bel ong to the so-called Pseudomonas rRNA group I (the authentic pseudomon ads) or to the Azotobacteraceae (free-living nitrogen-fixers), indicat e and confirm that both taxa are closely related. All strains show put rescine (PUT) and spermidine (SPD) in their pattern. The authentic pse udomonads could be split into a cadaverine lacking (CAD -) and a cadav erine containing (CAD +) group (including the type species Pseudomonas aeruginosa), while all (except Azomonas insignis) free-living nitroge n-fixers were CAD +. This observation also supports recent rRNA sequen ce data which show a phylogenetic closer relationship between Azotobac ter vinelandii and the Pseudomonas aeruginosa rRNA sublineage than bet ween Azotobacter vinelandii and the Pseudomonas fluorescens rRNA subli neage.