[Thermosensitivity of naphthalene biodegradation plasmids].
The object of the work was to study the functional expression of naphthalene and salicylic acid catabolism systems and the stability of naphthalene biodegradation plasmids NAH, pBS2, pBS3 and NPL-41 in Pseudomonas aeruginosa PAO. The catabolic systems of the plasmids were shown to be thermosensitive, with a slight variation between one another. The plasmids became unstable at a high temperature; the temperature of effective elimination was 41 degrees C for plasmids NPL-41 and pBS3, and 42 degrees C for plasmids NAH and pBS2. NAH and pBS2 produced a weak inhibiting effect while NPL-41 and pBS3 caused a strong inhibition of the PAO strain growth at 42 degrees C. As a result, many anomalous filamentous cells (partly in the state of lysis) appeared in the cultural broth. Only PAO cells that had lost their plasmid were capable of normal growth in a medium with MPA at an elevated temperature; this creates a convenient system for selection of clones that have lost the plasmids of naphthalene biodegradation. Some of these plasmids can inhibit growth of Pseudomonas strains at an elevated temperature; this fact should be taken into account when the capability of Pseudomonas to grow at a high temperature is used as a taxonomic feature.
D000222:Adaptation, Physiological; D001673:Biodegradation, Environmental; D006358:Hot Temperature; D009281:Naphthalenes / Q000378:metabolism*; D010957:Plasmids; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000378:metabolism
D009281:Naphthalenes
Termochuvstvitel'nost' plazmid biodegradatsii naftalina.