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 Ma, J.-F.
Right arrow Articles by Hassett, D. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ma, J.-F.
Right arrow Articles by Hassett, D. J.

 Previous Article  |  Next Article 

J Bacteriol, April 1998, p. 1741-1749, Vol. 180, No. 7
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Cloning and Characterization of the Pseudomonas aeruginosa zwf Gene Encoding Glucose-6-Phosphate Dehydrogenase, an Enzyme Important in Resistance to Methyl Viologen (Paraquat)

Ju-Fang Ma,1 Paul W. Hager,2 Michael L. Howell,1 Paul V. Phibbs,2 and Daniel J. Hassett1,*

Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0524,1 and Department of Microbiology and Immunology, East Carolina University School of Medicine, Greenville, North Carolina 278582

Received 25 November 1997/Accepted 28 January 1998

In this study, we cloned the Pseudomonas aeruginosa zwf gene, encoding glucose-6-phosphate dehydrogenase (G6PDH), an enzyme that catalyzes the NAD+- or NADP+-dependent conversion of glucose-6-phosphate to 6-phosphogluconate. The predicted zwf gene product is 490 residues, which could form a tetramer with a molecular mass of ~220 kDa. G6PDH activity and zwf transcription were maximal in early logarithmic phase when inducing substrates such as glycerol, glucose, or gluconate were abundant. In contrast, both G6PDH activity and zwf transcription plummeted dramatically when bacteria approached stationary phase, when inducing substrate was limiting, or when the organisms were grown in a citrate-, succinate-, or acetate-containing basal salts medium. G6PDH was purified to homogeneity, and its molecular mass was estimated to be ~220 kDa by size exclusion chromatography. Estimated Km values of purified G6PDH acting on glucose-6-phosphate, NADP+, and NAD+ were 530, 57, and 333 µM, respectively. The specific activities with NAD+ and NADP+ were calculated to be 176 and 69 µmol/min/mg. An isogenic zwf mutant was unable to grow on minimal medium supplemented with mannitol. The mutant also demonstrated increased sensitivity to the redox-active superoxide-generating agent methyl viologen (paraquat). Since one by-product of G6PDH activity is NADPH, the latter data suggest that this cofactor is essential for the activity of enzymes critical in defense against paraquat toxicity.


* Corresponding author. Mailing address: Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, 231 Bethesda Ave., Cincinnati, OH 45267-0524. Phone: (513) 558-1154 or (513) 558-0083. Fax: (513) 558-8474. E-mail: hassetdj{at}popmail.uc.edu.




This article has been cited by other articles:

  • Daddaoua, A., Krell, T., Ramos, J.-L. (2009). Regulation of Glucose Metabolism in Pseudomonas: THE PHOSPHORYLATIVE BRANCH AND ENTNER-DOUDOROFF ENZYMES ARE REGULATED BY A REPRESSOR CONTAINING A SUGAR ISOMERASE DOMAIN. J. Biol. Chem. 284: 21360-21368 [Abstract] [Full Text]  
  • Kim, J., Jeon, C. O., Park, W. (2008). Dual regulation of zwf-1 by both 2-keto-3-deoxy-6-phosphogluconate and oxidative stress in Pseudomonas putida. Microbiology 154: 3905-3916 [Abstract] [Full Text]  
  • del Castillo, T., Duque, E., Ramos, J. L. (2008). A Set of Activators and Repressors Control Peripheral Glucose Pathways in Pseudomonas putida To Yield a Common Central Intermediate. J. Bacteriol. 190: 2331-2339 [Abstract] [Full Text]  
  • del Castillo, T., Ramos, J. L., Rodriguez-Herva, J. J., Fuhrer, T., Sauer, U., Duque, E. (2007). Convergent Peripheral Pathways Catalyze Initial Glucose Catabolism in Pseudomonas putida: Genomic and Flux Analysis. J. Bacteriol. 189: 5142-5152 [Abstract] [Full Text]  
  • Bore, E., Langsrud, S., Langsrud, O., Rode, T. M., Holck, A. (2007). Acid-shock responses in Staphylococcus aureus investigated by global gene expression analysis. Microbiology 153: 2289-2303 [Abstract] [Full Text]  
  • Silo-Suh, L., Suh, S.-J., Phibbs, P. V., Ohman, D. E. (2005). Adaptations of Pseudomonas aeruginosa to the Cystic Fibrosis Lung Environment Can Include Deregulation of zwf, Encoding Glucose-6-Phosphate Dehydrogenase. J. Bacteriol. 187: 7561-7568 [Abstract] [Full Text]  
  • Parvatiyar, K., Alsabbagh, E. M., Ochsner, U. A., Stegemeyer, M. A., Smulian, A. G., Hwang, S. H., Jackson, C. R., McDermott, T. R., Hassett, D. J. (2005). Global Analysis of Cellular Factors and Responses Involved in Pseudomonas aeruginosa Resistance to Arsenite. J. Bacteriol. 187: 4853-4864 [Abstract] [Full Text]  
  • Velazquez, F., di Bartolo, I., de Lorenzo, V. (2004). Genetic Evidence that Catabolites of the Entner-Doudoroff Pathway Signal C Source Repression of the {sigma}54 Pu Promoter of Pseudomonas putida. J. Bacteriol. 186: 8267-8275 [Abstract] [Full Text]  
  • McLeish, M. J., Kneen, M. M., Gopalakrishna, K. N., Koo, C. W., Babbitt, P. C., Gerlt, J. A., Kenyon, G. L. (2003). Identification and Characterization of a Mandelamide Hydrolase and an NAD(P)+-Dependent Benzaldehyde Dehydrogenase from Pseudomonas putida ATCC 12633. J. Bacteriol. 185: 2451-2456 [Abstract] [Full Text]  
  • Schuster, M., Lostroh, C. P., Ogi, T., Greenberg, E. P. (2003). Identification, Timing, and Signal Specificity of Pseudomonas aeruginosa Quorum-Controlled Genes: a Transcriptome Analysis. J. Bacteriol. 185: 2066-2079 [Abstract] [Full Text]  
  • Hassett, D. J., Ochsner, U. A., Groce, S. L., Parvatiyar, K., Ma, J.-F., Lipscomb, J. D. (2000). Hydrogen Peroxide Sensitivity of Catechol-2,3-Dioxygenase: a Cautionary Note on Use of xylE Reporter Fusions under Aerobic Conditions. Appl. Environ. Microbiol. 66: 4119-4123 [Abstract] [Full Text]  
  • Hager, P. W., Calfee, M. W., Phibbs, P. V. (2000). The Pseudomonas aeruginosa devB/SOL Homolog, pgl, Is a Member of the hex Regulon and Encodes 6-Phosphogluconolactonase. J. Bacteriol. 182: 3934-3941 [Abstract] [Full Text]  
  • Willis, L. B., Walker, G. C. (1999). A Novel Sinorhizobium meliloti Operon Encodes an alpha -Glucosidase and a Periplasmic-Binding-Protein-Dependent Transport System for alpha -Glucosides. J. Bacteriol. 181: 4176-4184 [Abstract] [Full Text]