Our previous studies showed that the biodegradation of petroleum oil by
a pseudomonas isolated from a petroleum-contaminated soil was instable.
In this work, it is shown that when the isolates are immobilized on
Perlite, they are more stable for oil degradation. Although the isolate
did not have any chemotaxis to octadecane, dodecane and octane but
utilize octadecane and dodecane better than octane and it did not
utilized hexane, benzene, kerosene, pentane, heptane or thiophenol. The
generation time for degradation of petroleum oil, dodecane and
octadecane was 20, 22, and 25 h respectively. This phenotype was not
transformed to Pseudomonas by conjugation even with lysozyme
treatment, however the petroleum oil and octadecane utilization were
transformed to Escherichia coli by lysozyme treatment. The
transformed E. coli lost the ability to use octadecane after three
subcultures on nutrient broth and 34 generations
