Analyses of the acetate-producing pathways in Corynebacterium glutamicum under oxygen-deprived conditions
- 594 Downloads
Corynebacterium glutamicum R efficiently produces valuable chemicals from glucose under oxygen-deprived conditions. In an effort to reduce acetate as a byproduct, acetate productivity of several mutant-disrupted genes encoding possible key enzymes for acetate formation was determined. Disruption of the aceE gene that encodes the E1 enzyme of the pyruvate dehydrogenase complex resulted in almost complete elimination of acetate formation under oxygen-deprived conditions, implying that acetate synthesis under these conditions was essentially via acetyl-coenzyme A (CoA). Simultaneous disruption of pta, encoding phosphotransacetylase, and ack, encoding acetate kinase, resulted in no measurable change in acetate productivity. A mutant strain with disruptions in pta, ack and as-yet uncharacterized gene (cgR2472) exhibited 65% reduced acetate productivity compared to the parental strain, although a single disruption of cgR2472 exhibited no effect on acetate productivity. The gene cgR2472 was shown to encode a CoA-transferase (CTF) that catalyzes the formation of acetate from acetyl-CoA. These results indicate that PTA-ACK as well as CTF is involved in acetate production in C. glutamicum. This study provided basic information to reduce acetate production under oxygen-deprived conditions.
KeywordsAcetate-producing pathway Corynebacterium glutamicum CoA-transferase
We thank C. A. Omumasaba (RITE) for helpful comments on the manuscript. We are also grateful to S. Murakami for technical support. This research was financially supported in part by the New Energy and Industrial Technology Development Organization (NEDO), Japan.
- Chotani G, Dodge T, Hsu A, Kumar M, LaDuca R, Trimbur D, Weyler W, Sanford K (2000) The commercial production of chemicals using pathway engineering. Biochim Biophys Acta 1543:434–455Google Scholar
- Kinoshita S, Udaka S, Shimono M (1957) Studies on the amino acid fermentation: Part I. Production of L-glutamic acid by various microorganisms. J Gen Appl Microbiol 3:193–205Google Scholar
- Liedvogel B, Stumpf PK (1982) Origin of acetate in spinach leaf cell. Plant Physiol 69:897–903Google Scholar
- Nakata K, Inui M, Kos P, Vertès AA, Yukawa H (2003) Vectors for genetic engineering of Corynebacteria. In: Saha B (ed) American Chemical Society Symposium Series 862: fermentation biotechnology. American Chemical Society, Washington, DC, pp 175–191Google Scholar
- Presecan-Siedel E, Galinier A, Longin R, Deutscher J, Danchin A, Glaser P, Martin-Verstraete I (1999) Catabolite regulation of the pta gene as part of carbon flow pathways in Bacillus subtilis. J Bacteriol 181:6889–6897Google Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual. Cold Spring Harbor Laboratory, Cold Spring Harbor, NYGoogle Scholar
- Scherf U, Buckel W (1991) Purification and properties of 4-hydroxybutyrate coenzyme A transferase from Clostridium aminobutyricum. Appl Environ Microbiol 57:2699–2702Google Scholar
- Sohling B, Gottschalk G (1996) Molecular analysis of the anaerobic succinate degradation pathway in Clostridium kluyveri. J Bacteriol 178:871–880Google Scholar
- Terasawa M, Yukawa H (1993) Industrial production of biochemicals by native immobilization. In: Tanaka A, Tosaka O, Kobayashi T (eds) Industrial application of Immobilized biocatalysts. Marcel Dekker, New York, pp 37–52Google Scholar