Genetic Control of Enzyme Induction in the β-Ketoadipate Pathway ofPseudomonas putida:Deletion Mapping ofcatMutations

Abstract

A number of spontaneous mutant strains of Pseudomonas putida, obtained by repeated selection for inability to grow with cis,cis-muconate, have been shown to carry deletions in catB, the structural gene for muconate lactonizing enzyme. These strains have been employed for deletion mapping of the genetic region containing catB and catC (the structural gene for muconolactone isomerase, the synthesis of which is coordinate with that of muconate lactonizing enzyme). All deletions that overlap mutant sites located on the left side of the genetic map, as well as the point mutations in that region, lead to a pleiotropic loss of both catB and catC activities. We propose that this region to the left of catB has a regulatory function. Although the details of regulation at the molecular level are unclear, our data indicate that catB and catC may well be controlled by a mechanism unlike any yet described by workers on enteric bacteria.

Inducible Uptake System for β-Carboxy- cis, cis -muconate in a Permeability Mutant of Pseudomonas putida

“…All bacterial si rived from strain PRS1 (strain 90 in t Stanier et al [25]). Strain PRS2000 neous mutant selected on the basis ( grow at the expense of cis, cis-mucon ture of strain PRS1 (28). In the couri maintenance, strain PRS2000 lost its ENZYMES cis, cis-muconate so that now it is phenotypically indistinguishable from the wild-type strain PRS1.…”

“…Genetic investigations of the fluorescent pseudomonads have shown that the coordinately controlled enzymes of the ,B-ketoadipate pathway are encoded by tightly linked structural genes that may be members of complex operons (14,29). Support for this view came from the observation that the coordinately controlled muconate lactonizing enzyme and muconolactone isomerase of P. putida share a common regulatory gene which neighbors the structural gene for the former enzyme (28,31).…”

Mapping of ben genes of Pseudomonas aeruginosa

“…This study This study [4] * Bacterial genotype symbols are the same as those used by Bachmann [8] and Holloway and Zhang [9] except for per which signifies c/s, c/s-muconate permeability [10]. Plasmid phenotype symbols are used according to the proposals of Novick et al [11] except for the letter C, followed by a gene symbol, which shows the ability of the plasmid to complement the gene in the organism indicated [12].…”

Mapping of theben, antandcatgenes ofPseudomonas aeruginosaand evolutionary relationship of thebenregion ofP. aeruginosaandP. putida

“…These are listed in Table 1. This study This study [7] [8] [9] This study This study This study This study [4] Km * Bacterial genotype symbols are the same as those used by Bachmann [11] and Holloway and Zhang [12] except for per which signifies c/s, c/s-muconate permeability [6]. Plasmid phenotype symbols are used according to the proposals of Novick et al [13] except for the letter C, followed by a gene symbol, which shows the ability of the plasmid to complement the gene in the organism indicated [14].…”