Volatile ketone formation in bacteria: Release of 3-oxopentanoate by soil pseudomonads during growth on heptanoate

• Published in: Current microbiology Vol. 42; no. 4; pp. 276 - 281
• Main Authors: MATIASEK, Michael G, CHOUDHURY, Keka, NEMECEK-MARSHALL, Michele, FALL, Ray
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 01.04.2001; Springer Nature B.V
• Subjects: 3-Oxopentanoic acid; Acetoacetate decarboxylase; Acetone - metabolism; Agronomy. Soil science and plant productions; Bacteria; Biochemistry and biology; Biological and medical sciences; Butanones - metabolism; Carbon sources; Carboxy-Lyases - metabolism; Chemical, physicochemical, biochemical and biological properties; Chromatography, Gas; Fundamental and applied biological sciences. Psychology; Gas chromatography; heptanoic acid; Heptanoic Acids - metabolism; Ketones; Microbiology; Oxygen - metabolism; Pentanoic Acids - metabolism; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Polyhydroxyalkanoates; Pseudomonas - growth & development; Pseudomonas - metabolism; Pseudomonas aureofaciens; Pseudomonas fluorescens; Pseudomonas putida; Soil Microbiology; Soil science; Substrate Specificity; Pseudomonadales; 2-Butanone; Volatile compound; Pseudomonas aureofaciens; Soils; Bacteria; Pseudomonadaceae; Pseudomonas fluorescens; Ketone; Pseudomonas putida; Release; Acetone
• ISSN: 0343-8651; 1432-0991
• DOI: 10.1007/s002840110217

During enrichments to search for soil bacteria that form the volatile ketones, acetone and butanone, we isolated pure cultures of Pseudomonas aureofaciens, P. fluorescens, and P. putida that excrete the beta-keto-acid, 3-oxopentanoate (3-OPA), when grown on heptanoic acid as carbon source. Analysis of 3-OPA used enzymatic decarboxylation by acetoacetate decarboxylase to yield butanone, which was detected by headspace gas chromatography. The formation of 3-OPA was strongly dependent on heptanoic acid concentration, the level of oxygen, and the state of growth, and was not seen with even-chain or other odd-chain fatty acids. Uptake of 3-OPA during stationary phase of growth is probably related to polyhydroxyalkanoate (PHA) formation in these isolates. A model for formation and release of 3-OPA is proposed.