| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
elle1,*Institut de Pharmacologie et de Biologie Structurale du CNRS and Université Paul Sabatier, 205 route de Narbonne, 31077 Toulouse cedex, France
ABSTRACT
Initial transport kinetics of isoniazid (INH) and its uptake at the plateau were studied in Mycobacterium tuberculosis H37Rv under various experimental conditions. The initial uptake velocity increased linearly with INH concentration from 2 x 10-6 M to 10-2 M. It was modified neither by addition of a protonophore that abolished proline transport, nor following ATP depletion by arsenate, which inhibited glycerol uptake, two transport processes taken as controls for secondary active transport and facilitated diffusion, respectively. Microaerobiosis or low temperature (4 °) were without effect on initial uptake. It is thus likely that INH transport in M. tuberculosis proceeds by a passive diffusion mechanism, and that catalase-peroxidase (KatG) is not involved in the actual transport. However, conditions inhibiting KatG activity (high INH concentration, microaerobiosis, low temperature) decrease cell radioactivity at the uptake plateau. It is proposed that INH transport occurs by passive diffusion. KatG is involved only in the intracellular accumulation of oxidized derivatives of INH, especially of isonicotinic acid, which is trapped inside cells in its ionized form. This model explains observed and previously known characteristics of the accumulation of radioactivity in the presence of [14C]INH for various species and strains of mycobacteria.
*Author for correspondence: Gilbert Laneelle. Tel: +33 5 61 17 55 70. Fax: +33 5 61 17 59 94.
This article has been cited by other articles:
|
|
 |
|
  G. Varela, S. Gonzalez, P. Gadea, C. Coitinho, I. Mota, G. Gonzalez, F. Goni, C. Rivas, and F. Schelotto Prevalence and dissemination of the Ser315Thr substitution within the KatG enzyme in isoniazid-resistant strains of Mycobacterium tuberculosis isolated in Uruguay J. Med. Microbiol., December 1, 2008; 57(12): 1518 - 1522. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Gebhardt, X. Meniche, M. Tropis, R. Kramer, M. Daffe, and S. Morbach The key role of the mycolic acid content in the functionality of the cell wall permeability barrier in Corynebacterineae Microbiology, May 1, 2007; 153(5): 1424 - 1434. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Zhang, J. Yue, Y.-p. Yang, H.-m. Zhang, J.-q. Lei, R.-l. Jin, X.-l. Zhang, and H.-h. Wang Detection of Mutations Associated with Isoniazid Resistance in Mycobacterium tuberculosis Isolates from China J. Clin. Microbiol., November 1, 2005; 43(11): 5477 - 5482. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Etienne, F. Laval, C. Villeneuve, P. Dinadayala, A. Abouwarda, D. Zerbib, A. Galamba, and M. Daffe The cell envelope structure and properties of Mycobacterium smegmatis mc2155: is there a clue for the unique transformability of the strain? Microbiology, June 1, 2005; 151(6): 2075 - 2086. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Stephan, C. Mailaender, G. Etienne, M. Daffe, and M. Niederweis Multidrug Resistance of a Porin Deletion Mutant of Mycobacterium smegmatis Antimicrob. Agents Chemother., November 1, 2004; 48(11): 4163 - 4170. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. F. Cardoso, R. C. Cooksey, G. P. Morlock, P. Barco, L. Cecon, F. Forestiero, C. Q. F. Leite, D. N. Sato, M. d. L. Shikama, E. M. Mamizuka, et al. Screening and Characterization of Mutations in Isoniazid-Resistant Mycobacterium tuberculosis Isolates Obtained in Brazil Antimicrob. Agents Chemother., September 1, 2004; 48(9): 3373 - 3381. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Mailaender, N. Reiling, H. Engelhardt, S. Bossmann, S. Ehlers, and M. Niederweis The MspA porin promotes growth and increases antibiotic susceptibility of both Mycobacterium bovis BCG and Mycobacterium tuberculosis Microbiology, April 1, 2004; 150(4): 853 - 864. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. J. Hearn and M. H. Cynamon Design and synthesis of antituberculars: preparation and evaluation against Mycobacterium tuberculosis of an isoniazid Schiff base J. Antimicrob. Chemother., February 1, 2004; 53(2): 185 - 191. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. V. Ramaswamy, R. Reich, S.-J. Dou, L. Jasperse, X. Pan, A. Wanger, T. Quitugua, and E. A. Graviss Single Nucleotide Polymorphisms in Genes Associated with Isoniazid Resistance in Mycobacterium tuberculosis Antimicrob. Agents Chemother., April 1, 2003; 47(4): 1241 - 1250. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Etienne, C. Villeneuve, H. Billman-Jacobe, C. Astarie-Dequeker, M.-A. Dupont, and M. Daffe The impact of the absence of glycopeptidolipids on the ultrastructure, cell surface and cell wall properties, and phagocytosis of Mycobacterium smegmatis Microbiology, October 1, 2002; 148(10): 3089 - 3100. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Marrakchi, G. Lanéelle, and A. Quémard InhA, a target of the antituberculous drug isoniazid, is involved in a mycobacterial fatty acid elongation system, FAS-II Microbiology, February 1, 2000; 146(2): 289 - 296. [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 | |
