Insertion element analysis and mapping of the Pseudomonas plasmid alk regulon

M Fennewald, S Benson, M Oppici, J Shapiro
1979 Journal of Bacteriology  
We characterized and mapped new mutations of the alk (alkane utilization) genes found on Pseudomonas plasmids of the Inc P-2 group. These mutations were isolated after (i) nitrosoguanidine mutagenesis, (ii) transposition of the Tn7 trimethoprim and streptomycin resistance determinant, and (iii) reversion of polarity effects of alk::Tn7 insertion mutations. Our results indicate the existence of two alk loci not previously described-alkD, whose product is required for synthesis of membrane
more » ... of membrane alkane-oxidizing activites, and alkE, whose product is required for synthesis of inducible membrane alcohol dehydrogenase activity. Polarity of al/::Tn7 insertion mutations indicates the existence of an alkBAE operon. Mapping of alk loci by transduction in P. shows that there are at least three alk clusters in the CAM-OCT plasmid-alkRD, containing regulatory genes; alkBAE, containing genes for specific biochemical activities; and alkC, containing one or more genes needed for normal synthesis of membrane alcohol dehydrogenase. The alkRD and alkBAE cluster-s are linked but separated by about 42 kilobases. The alkC cluster is not linked to either of the other two alk regions. Altogether, these results indicate a complex genetic control of the alkane utilization phenotype in P. putida and P. aeruginosa involving at least six separate genes.
doi:10.1128/jb.139.3.940-952.1979 fatcat:sawmfrv7kbczppnxnu52iq2i3q