Subbaiah, T V and Mitchison, D A and Selkon, J B (1960) The Susceptibility to Hydrogen Peroxide of Indian and British Isoniazid-Sensitive and Isoniazid- Resistant Tubercle Bacilli. Tubercle, 41 (5). pp. 323-333. ISSN 0041-3879
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Abstract
The present work describes an attempt to modify the method of Kreis and Le Joubioux (1957a) so that it would accurately estimate the relative proportions of catalase-positive and catalase-negative organisms in strains containing mixtures of the two types. A bactericidal test was chosen in preference to a bacteriostatic test, since it is difficult to obtain quantitative measurement with the latter technique. In performing a bactericidal test residual peroxide must be inactivated or removed by dilution so that it does not inhibit the growth of surviving organisms. Knox, Meadow and Worssam (1956) removed peroxide by centrifugation and washing, but this method was considered impracticable if this test were to be used on a large scale, and likely to produce inaccurate counts on the surviving organisms. In the present work the method of removal of peroxide was studied as well as the determination of the optimal peroxide concentration and period of exposure which would kill all catalase-negative organisms, but would leave catalase-positive organisms unaffected. In addition, the method of Kreis & Le Joubioux (1957a) was modified by reducing the inoculum of organisms exposed to peroxide so that catalase-positive bacilli would not be able to destroy peroxide during the test itself. The standardised bactericidal test was then employed in comparing the susceptibility to peroxide of isoniazid-sensitive strains from British and Indian patients, and in investigating the relationship between the peroxide susceptibility and the catalase activity of their isoniazid-resistant mutant strains.
Item Type: | Article |
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Subjects: | Tuberculosis > Clinical Research |
Divisions: | Clinical Research |
Depositing User: | Dr. Rathinasabapati R |
Date Deposited: | 12 Jul 2013 10:50 |
Last Modified: | 23 Feb 2016 10:39 |
URI: | http://eprints.nirt.res.in/id/eprint/19 |
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