Previous Article | Next Article 
Journal of Bacteriology, February 2001, p. 1038-1046, Vol. 183, No. 3
0021-9193/01/$04.00+0 DOI: 10.1128/JB.183.3.1038-1046.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Connection between Poly-
-Hydroxybutyrate
Biosynthesis and Growth on C1 and C2 Compounds
in the Methylotroph Methylobacterium extorquens
AM1
Natalia
Korotkova1 and
Mary E.
Lidstrom1,2,*
Department of Chemical
Engineering1 and Department of
Microbiology,2 University of Washington,
Seattle, Washington 98195-1750
Received 3 August 2000/Accepted 7 November 2000
Several DNA regions containing genes involved in
poly-
-hydroxybutyrate (PHB) biosynthesis and degradation and also in
fatty acid degradation were identified from genomic sequence data and have been characterized in the serine cycle facultative methylotroph Methylobacterium extorquens AM1. Genes involved in PHB
biosynthesis include those encoding
-ketothiolase
(phaA), NADPH-linked acetoacetyl coenzyme A (acetyl-CoA)
reductase (phaB), and PHB synthase (phaC). phaA and phaB are closely linked on the
chromosome together with a third gene with identity to a regulator of
PHB granule-associated protein, referred to as orf3.
phaC was unlinked to phaA and phaB. Genes involved in PHB degradation include two unlinked genes predicted to encode intracellular PHB depolymerases (depA and
depB). These genes show a high level of identity with each
other at both DNA and amino acid levels. In addition, a gene encoding
-hydroxybutyrate dehydrogenase (hbd) was identified.
Insertion mutations were introduced into depA, depB, phaA, phaB,
phaC, and hbd and also in a gene predicted to encode
crotonase (croA), which is involved in fatty acid
degradation, to investigate their role in PHB cycling. Mutants in
depA, depB, hbd, and croA all produced normal
levels of PHB, and the only growth phenotype observed was the inability
of the hbd mutant to grow on
-hydroxybutyrate. However,
the phaA, phaB, and phaC mutants all showed
defects in PHB synthesis. Surprisingly, these mutants also showed
defects in growth on C1 and C2 compounds and,
for phaB, these defects were rescued by glyoxylate
supplementation. These results suggest that
-hydroxybutyryl-CoA is
an intermediate in the unknown pathway that converts acetyl-CoA to
glyoxylate in methylotrophs and Streptomyces spp.
*
Corresponding author. Mailing address: Department of
Chemical Engineering, University of Washington, Box 351750, Seattle, WA
98195-1750. (206) 616-5282. Fax: (206) 616-5721. E-mail:
lidstrom{at}u.washington.edu.
Journal of Bacteriology, February 2001, p. 1038-1046, Vol. 183, No. 3
0021-9193/01/$04.00+0 DOI: 10.1128/JB.183.3.1038-1046.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Zarzycki, J., Schlichting, A., Strychalsky, N., Muller, M., Alber, B. E., Fuchs, G.
(2008). Mesaconyl-Coenzyme A Hydratase, a New Enzyme of Two Central Carbon Metabolic Pathways in Bacteria. J. Bacteriol.
190: 1366-1374
[Abstract]
[Full Text]
-
Yamada, M., Yamashita, K., Wakuda, A., Ichimura, K., Maehara, A., Maeda, M., Taguchi, S.
(2007). Autoregulator Protein PhaR for Biosynthesis of Polyhydroxybutyrate [P(3HB)] Possibly Has Two Separate Domains That Bind to the Target DNA and P(3HB): Functional Mapping of Amino Acid Residues Responsible for DNA Binding. J. Bacteriol.
189: 1118-1127
[Abstract]
[Full Text]
-
Gourion, B., Rossignol, M., Vorholt, J. A.
(2006). A proteomic study of Methylobacterium extorquens reveals a response regulator essential for epiphytic growth. Proc. Natl. Acad. Sci. USA
103: 13186-13191
[Abstract]
[Full Text]
-
Wang, C., Meek, D. J., Panchal, P., Boruvka, N., Archibald, F. S., Driscoll, B. T., Charles, T. C.
(2006). Isolation of Poly-3-Hydroxybutyrate Metabolism Genes from Complex Microbial Communities by Phenotypic Complementation of Bacterial Mutants. Appl. Environ. Microbiol.
72: 384-391
[Abstract]
[Full Text]
-
Korotkova, N., Lidstrom, M. E., Chistoserdova, L.
(2005). Identification of Genes Involved in the Glyoxylate Regeneration Cycle in Methylobacterium extorquens AM1, Including Two New Genes, meaC and meaD. J. Bacteriol.
187: 1523-1526
[Abstract]
[Full Text]
-
Kelley, S. T., Theisen, U., Angenent, L. T., St. Amand, A., Pace, N. R.
(2004). Molecular Analysis of Shower Curtain Biofilm Microbes. Appl. Environ. Microbiol.
70: 4187-4192
[Abstract]
[Full Text]
-
Chistoserdova, L., Chen, S.-W., Lapidus, A., Lidstrom, M. E.
(2003). Methylotrophy in Methylobacterium extorquens AM1 from a Genomic Point of View. J. Bacteriol.
185: 2980-2987
[Full Text]
-
Marx, C. J., O'Brien, B. N., Breezee, J., Lidstrom, M. E.
(2003). Novel Methylotrophy Genes of Methylobacterium extorquens AM1 Identified by using Transposon Mutagenesis Including a Putative Dihydromethanopterin Reductase. J. Bacteriol.
185: 669-673
[Abstract]
[Full Text]
-
Korotkova, N., Chistoserdova, L., Lidstrom, M. E.
(2002). Poly-{beta}-Hydroxybutyrate Biosynthesis in the Facultative Methylotroph Methylobacterium extorquens AM1: Identification and Mutation of gap11, gap20, and phaR. J. Bacteriol.
184: 6174-6181
[Abstract]
[Full Text]
-
Encarnacion, S., del Carmen Vargas, M., Dunn, M. F., Davalos, A., Mendoza, G., Mora, Y., Mora, J.
(2002). AniA Regulates Reserve Polymer Accumulation and Global Protein Expression in Rhizobium etli. J. Bacteriol.
184: 2287-2295
[Abstract]
[Full Text]
-
Korotkova, N., Chistoserdova, L., Kuksa, V., Lidstrom, M. E.
(2002). Glyoxylate Regeneration Pathway in the Methylotroph Methylobacterium extorquens AM1. J. Bacteriol.
184: 1750-1758
[Abstract]
[Full Text]