Hydrocarbon assimilation and biosurfactant production in Pseudomonas aeruginosa mutants

Journal Article · Mon Jul 01 04:00:00 EDT 1991 · Journal of Bacteriology; (United States)

OSTI ID:5697382

Koch, A K; Fiechter, A; Reiser, J ^[1]; Kaeppeli, O ^[2]

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1. Inst. for Biotechnology, Zuerich (Switzerland)
2. BIDECO AG, Duebendorf (Switzerland)

The authors isolated transposon Tn5-GM-induced mutants of Pseudomonas aeruginosa PG201 that were unable to grow in minimal media containing hexadecane as a carbon source. Some of these mutants lacked extracellular rhamnolipids, as shown by measuring the surface and interfacial tensions of the cell culture supernatants. Furthermore, the concentrated culture media of the mutant strains were tested for the presence of rhamnolipids by thin-layer chromatography and for rhamnolipid activities, including hemolysis and growth inhibition of Bacillus subtilis. Mutant 65E12 was unable to produce extracellular rhamnolipids under any of the inhibition of Bacillus subtilis. Mutant 65E12 was unable to produce extracellular rhamnolipids under any of the conditions tested, lacked the capacity to take up {sup 14}C-labeled hexadecane, and did not grow in media containing individual alkanes with chain lengths ranging from C{sub 12} to C{sub 19}. However, growth on these alkanes and uptake of ({sup 14}C)hexadecane were restored when small amounts of purified rhamnolipids were added to the cultures. Mutant 59C7 was unable to grow in media containing hexadecane, nor was it able to take up ({sup 14}C)hexadecane uptake. The addition of small amounts of rhamnolipids restored on alkanes and ({sup 14}C)hexadecane uptake. In glucose-containing media, however, mutant 59C7 produced rhamnolipids at levels about twice as high as those of the wild-type strain. These results show that rhamnolipids play a major role in hexadecane uptake and utilization by P.aeruginosa.

• OSTI ID: 5697382
• Journal Information: Journal of Bacteriology; (United States), Journal Name: Journal of Bacteriology; (United States) Vol. 173:13; ISSN JOBAA; ISSN 0021-9193
• Country of Publication: United States
• Language: English

Related Subjects

551000* -- Physiological Systems
59 BASIC BIOLOGICAL SCIENCES
ALKANES
BACTERIA
BIOSYNTHESIS
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
HEXADECANE
HYDROCARBONS
LABELLED COMPOUNDS
LIPIDS
METABOLISM
MICROORGANISMS
MUTANTS
ORGANIC COMPOUNDS
PHYSIOLOGY
PSEUDOMONAS
SURFACTANTS
SYNTHESIS
TRANSPOSONS