Organization and control of genes encoding catabolic enzymes in Rhizobiaceae. Progress report, March 1993

Technical Report · Mon Mar 01 04:00:00 EST 1993

DOI:https://doi.org/10.2172/10134071· OSTI ID:10134071

Parke, D; Ornston, L N

Rhizobiaceae, a diverse bacterial group comprising rhizobia and agrobacteria, symbiotic partnership with plants form nitrogen-fixing nodules on plant roots or are plant pathogens. Phenolic compounds produced by plants serve as inducers of rhizobial nodulation genes and agrobacterial virulence genes reflect their capacity to utilize numerous aromatics, including phenolics, as a source of carbon and energy. In many microbes the aerobic degradation of numerous aromatic compounds to tricarboxylic acid cycle intermediates is achieved by the {beta}-ketoadipate pathway. Our initial studies focused on the organization and regulation of the ketoadipate pathway in Agrobacterium tumefaciens. We have cloned, identified and characterized a novel regulatory gene that modulates expression of an adjacent pca (protocatechuate) structural gene, pcaD. Regulation of pcaD is mediated by the regulatory gene, termed pcaQ, in concert with the intermediate {beta}-carboxy-cis,cis-muconate. {beta}-carboxy-cis,cismuconate is an unstable chemical, not marketed commercially, and it is unlikely to permeate Escherichia coli cells if supplied in media. Because of these factors, characterization of pcaQ in E. coli required an in vivo delivery system for {beta}-carboxycis,cis-muconate. This was accomplished by designing an E. coli strain that expressed an Acinetobacter calcoaceticus pcaA gene for conversion of protocatechuate to {beta}-carboxy-cis,cis-muconate.

• Research Organization: Yale Univ., New Haven, CT (United States). Dept. of Biology
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-88ER13947
• OSTI ID: 10134071
• Report Number(s): DOE/ER/13947--4; ON: DE93010353
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090900
550200
550400
550500
553000
59 BASIC BIOLOGICAL SCIENCES
60 APPLIED LIFE SCIENCES
AGRICULTURE AND FOOD TECHNOLOGY
BIOCHEMISTRY
BIODEGRADATION
BIOLOGICAL PATHWAYS
CATABOLISM
DNA-CLONING
GENE OPERONS
GENE REGULATION
GENES
GENETICS
METABOLISM
MOLECULAR BIOLOGY
PHENOLS
PROCESSING
PROGRESS REPORT
RHIZOBIUM