This Article Full Text (PDF) Other Versions of this Article: JB.00254-07v1 189/14/5257    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gande, R. Articles by Eggeling, L. Search for Related Content PubMed PubMed Citation Articles by Gande, R. Articles by Eggeling, L.

 Previous Article  |  Next Article 

J. Bacteriol. doi:10.1128/JB.00254-07
Copyright (c) 2007, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.

The two carboxylases of Corynebacterium glutamicum essential for fatty acid and mycolic acid synthesis

Institute for Biotechnology, Research Centre Juelich, D-52425 Juelich, Germany, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom, and Kansai University High Technology Research Center, Suita-shi, Osaka 564-8680, Japan

^* To whom correspondence should be addressed. Email: l.eggeling{at}fz-juelich.de.

	Abstract

The suborder Corynebacterianeae comprises bacteria like Mycobacterium tuberculosis and Corynebacterium glutamicum and these bacteria contain in addition to the linear fatty acids, unique -branched -hydoxy fatty acids, called mycolic acids. Whereas acetyl-CoA carboxylase activity is required to provide malonyl-CoA for fatty acid synthesis, a new type of carboxylase is apparently additionally present in these bacteria. It activates the -carbon of a linear fatty acid by carboxylation thus enabling its decarboxylative condensation with a second fatty acid to afford mycolic acid synthesis. We now show that the acetyl-CoA carboxylase of C. glutamicum consists of the biotinylated -subunit AccBC, the -subunit AccD1, and the small peptide AccE of 8.9 kDa, forming an active complex of approx 812,000 Da. The carboxylase involved in mycolic acid synthesis is made up of the two highly similar -subunits AccD2 and AccD3, and of AccBC and AccE, the latter two identical to that of the acetyl-CoA carboxylase complex. Since AccD2 and AccD3 orthologous are present in all Corynebacterianeae these polypeptides are vital for mycolic acid synthesis forming the unique hydrophobic outer layer of these bacteria, and we speculate that the two -subunits present serve to lend specificity to this unique large multienzyme complex.

This article has been cited by other articles:

• Aguilar, J. A., Diaz-Perez, C., Diaz-Perez, A. L., Rodriguez-Zavala, J. S., Nikolau, B. J., Campos-Garcia, J. (2008). Substrate Specificity of the 3-Methylcrotonyl Coenzyme A (CoA) and Geranyl-CoA Carboxylases from Pseudomonas aeruginosa. J. Bacteriol. 190: 4888-4893 [Abstract] [Full Text]