This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by McCool, G. J.
Right arrow Articles by Cannon, M. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by McCool, G. J.
Right arrow Articles by Cannon, M. C.

 Previous Article  |  Next Article 

Journal of Bacteriology, July 2001, p. 4235-4243, Vol. 183, No. 14
0021-9193/01/$04.00+0   DOI: 10.1128/JB.183.14.4235-4243.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

PhaC and PhaR Are Required for Polyhydroxyalkanoic Acid Synthase Activity in Bacillus megaterium

Gabriel J. McCool and Maura C. Cannon*

Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003

Received 10 January 2001/Accepted 16 April 2001

Polyhydroxyalkanoic acids (PHAs) are a class of polyesters stored in inclusion bodies and found in many bacteria and in some archaea. The terminal step in the synthesis of PHA is catalyzed by PHA synthase. Genes encoding this enzyme have been cloned, and the primary sequence of the protein, PhaC, is deduced from the nucleotide sequences of more than 30 organisms. PHA synthases are grouped into three classes based on substrate range, molecular mass, and whether or not there is a requirement for phaE in addition to the phaC gene product. Here we report the results of an analysis of a PHA synthase that does not fit any of the described classes. This novel PHA synthase from Bacillus megaterium required PhaC (PhaCBm) and PhaR (PhaRBm) for activity in vivo and in vitro. PhaCBm showed greatest similarity to the PhaCs of class III in both size and sequence. Unlike those in class III, the 40-kDa PhaE was not required, and furthermore, the 22-kDa PhaRBm had no obvious homology to PhaE. Previously we showed that PhaCBm, and here we show that PhaRBm, is localized to inclusion bodies in living cells. We show that two forms of PHA synthase exist, an active form in PHA-accumulating cells and an inactive form in nonaccumulating cells. PhaC was constitutively produced in both cell types but was more susceptible to protease degradation in the latter type. Our data show that the role of PhaR is posttranscriptional and that it functions directly or indirectly with PhaCBm to produce an active PHA synthase.

* Corresponding author. Mailing address: Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003. Phone: (413) 545-0092. Fax: (413) 545-3291. E-mail:mcannon{at}bio.umass.edu.

Journal of Bacteriology, July 2001, p. 4235-4243, Vol. 183, No. 14
0021-9193/01/$04.00+0   DOI: 10.1128/JB.183.14.4235-4243.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:

  • Jahns, A. C., Rehm, B. H. A. (2009). Tolerance of the Ralstonia eutropha Class I Polyhydroxyalkanoate Synthase for Translational Fusions to Its C Terminus Reveals a New Mode of Functional Display. Appl. Environ. Microbiol. 75: 5461-5466 [Abstract] [Full Text]  
  • Chen, H.-J., Pan, S.-C., Shaw, G.-C. (2009). Identification and Characterization of a Novel Intracellular Poly(3-Hydroxybutyrate) Depolymerase from Bacillus megaterium. Appl. Environ. Microbiol. 75: 5290-5299 [Abstract] [Full Text]  
  • Jendrossek, D. (2009). Polyhydroxyalkanoate Granules Are Complex Subcellular Organelles (Carbonosomes). J. Bacteriol. 191: 3195-3202 [Full Text]  
  • Lu, Q., Han, J., Zhou, L., Zhou, J., Xiang, H. (2008). Genetic and Biochemical Characterization of the Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) Synthase in Haloferax mediterranei. J. Bacteriol. 190: 4173-4180 [Abstract] [Full Text]  
  • Christie, G., Lazarevska, M., Lowe, C. R. (2008). Functional Consequences of Amino Acid Substitutions to GerVB, a Component of the Bacillus megaterium Spore Germinant Receptor. J. Bacteriol. 190: 2014-2022 [Abstract] [Full Text]  
  • Christie, G., Lowe, C. R. (2007). Role of Chromosomal and Plasmid-Borne Receptor Homologues in the Response of Bacillus megaterium QM B1551 Spores to Germinants. J. Bacteriol. 189: 4375-4383 [Abstract] [Full Text]  
  • Tseng, C.-L., Chen, H.-J., Shaw, G.-C. (2006). Identification and Characterization of the Bacillus thuringiensis phaZ Gene, Encoding New Intracellular Poly-3-Hydroxybutyrate Depolymerase. J. Bacteriol. 188: 7592-7599 [Abstract] [Full Text]  
  • Lee, T.-R., Lin, J.-S., Wang, S.-S., Shaw, G.-C. (2004). PhaQ, a New Class of Poly-{beta}-Hydroxybutyrate (PHB)-Responsive Repressor, Regulates phaQ and phaP (Phasin) Expression in Bacillus megaterium through Interaction with PHB. J. Bacteriol. 186: 3015-3021 [Abstract] [Full Text]  
  • Mannhaupt, G., Montrone, C., Haase, D., Mewes, H. W., Aign, V., Hoheisel, J. D., Fartmann, B., Nyakatura, G., Kempken, F., Maier, J., Schulte, U. (2003). What's in the genome of a filamentous fungus? Analysis of the Neurospora genome sequence. Nucleic Acids Res 31: 1944-1954 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»