|
|
||||||||
The Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
Author for correspondence: John K. Guest. Tel: +44 114 222 4406/3. Fax: + 44 114 2728697 e-mail: J.R.Guest@Sheffield.ac.uk
ABSTRACT
Escherichia coli contains two genes (acnA and acnB) encoding aconitase activities. An acnB mutant was engineered by replacing the chromosomal acnB gene by an internally deleted derivative containing a tetR cassette. An acnB double mutant was then made by transducing a previously constructed acnA::kanR mutation into the acnB::tetR strain. Western blotting confirmed that the AcnA and AcnB proteins were no longer produced by the corresponding mutants and PCR analysis showed that the chromosomal acnB gene had been replaced by the disrupted gene. Aerobic and anaerobic growth in glucose minimal medium were impaired but not abolished by the acnB mutation, indicating that the lesion is partially complemented by the acnA+ gene, and growth was enhanced by glutamate. The acnAB double mutant would not grow on unsupplemented glucose minimal medium and although it responded to glutamate like a typical auxotroph under anaerobic conditions, under aerobic conditions no response to glutamate was observed before it was over-grown by revertants lacking citrate synthase (acnAB gltA). The acnAB double mutant retained a low but significant aconitase activity (<5% of wild-type), designated AcnC. Enzymological and regulatory studies with acn-lacZ fusions indicated that AcnB is the major aconitase, which is synthesized earlier in the growth cycle than AcnA, and subject to catabolite and anaerobic repression.
This article has been cited by other articles:
![]() |
U. Koziol, L. Hannibal, M. C. Rodriguez, E. Fabiano, M. L. Kahn, and F. Noya Deletion of Citrate Synthase Restores Growth of Sinorhizobium meliloti 1021 Aconitase Mutants J. Bacteriol., December 15, 2009; 191(24): 7581 - 7586. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. O. Han, M. Inui, and H. Yukawa Effect of carbon source availability and growth phase on expression of Corynebacterium glutamicum genes involved in the tricarboxylic acid cycle and glyoxylate bypass Microbiology, October 1, 2008; 154(10): 3073 - 3083. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Djaman, F. W. Outten, and J. A. Imlay Repair of Oxidized Iron-Sulfur Clusters in Escherichia coli J. Biol. Chem., October 22, 2004; 279(43): 44590 - 44599. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. R. Wyborn, A. Clark, R. E. Roberts, S. J. Jamieson, S. Tzokov, P. A. Bullough, T. J. Stillman, P. J. Artymiuk, J. E. Galen, L. Zhao, et al. Properties of haemolysin E (HlyE) from a pathogenic Escherichia coli avian isolate and studies of HlyE export Microbiology, May 1, 2004; 150(5): 1495 - 1505. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. P. Burgard, E. V. Nikolaev, C. H. Schilling, and C. D. Maranas Flux Coupling Analysis of Genome-Scale Metabolic Network Reconstructions Genome Res., February 1, 2004; 14(2): 301 - 312. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. W. Covert and B. O. Palsson Transcriptional Regulation in Constraints-based Metabolic Models of Escherichia coli J. Biol. Chem., July 26, 2002; 277(31): 28058 - 28064. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. B. Helling, B. K. Janes, H. Kimball, T. Tran, M. Bundesmann, P. Check, D. Phelan, and C. Miller Toxic Waste Disposal in Escherichia coli J. Bacteriol., July 1, 2002; 184(13): 3699 - 3703. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. E. Walden From bacteria to mitochondria: Aconitase yields surprises PNAS, April 2, 2002; 99(7): 4138 - 4140. [Full Text] [PDF] |
||||
![]() |
Y. Tang, M. A. Quail, P. J. Artymiuk, J. R. Guest, and J. Green Escherichia coli aconitases and oxidative stress: post-transcriptional regulation of sodA expression Microbiology, April 1, 2002; 148(4): 1027 - 1037. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Blank, J. Green, and J. R. Guest AcnC of Escherichia coli is a 2-methylcitrate dehydratase (PrpD) that can use citrate and isocitrate as substrates Microbiology, January 1, 2002; 148(1): 133 - 146. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Schwartz, S. Kaspar, G. Kienzlen, K. Muschko, and W. Wohlleben Inactivation of the Tricarboxylic Acid Cycle Aconitase Gene from Streptomyces viridochromogenes Tu494 Impairs Morphological and Physiological Differentiation J. Bacteriol., November 15, 1999; 181(22): 7131 - 7135. [Abstract] [Full Text] |
||||
![]() |
Y. Tang and J. R. Guest Direct evidence for mRNA binding and post-transcriptional regulation by Escherichia coli aconitases Microbiology, November 1, 1999; 145(11): 3069 - 3079. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Somerville, C. A. Mikoryak, and L. Reitzer Physiological Characterization of Pseudomonas aeruginosa during Exotoxin A Synthesis: Glutamate, Iron Limitation, and Aconitase Activity J. Bacteriol., February 15, 1999; 181(4): 1072 - 1078. [Abstract] [Full Text] |
||||
![]() |
M. M. Nakano, P. Zuber, and A. L. Sonenshein Anaerobic Regulation of Bacillus subtilis Krebs Cycle Genes J. Bacteriol., July 1, 1998; 180(13): 3304 - 3311. [Abstract] [Full Text] |
||||
![]() |
A. S. Gort and J. A. Imlay Balance between Endogenous Superoxide Stress and Antioxidant Defenses J. Bacteriol., March 15, 1998; 180(6): 1402 - 1410. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
| J MED MICROBIOL | ALL SGM JOURNALS | |