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

 Previous Article  |  Next Article 

Antimicrob Agents Chemother. 1977 March; 11(3): 534-540
Copyright © 1977 American Society for Microbiology. All Rights Reserved.

Effect of Ethambutol on the Viable Cell Count in Mycobacterium smegmatis

Center for Disease Control, Atlanta, Georgia 30333

ABSTRACT

Soon after a strain of Mycobacterium smegmatis was exposed to ethambutol (EMB), the number of viable cells increased dramatically above the number in a drug-free control. This rapid rise did not occur when the culture was maintained at 4°C instead of 37°C, when an EMB-resistant mutant was used, when auxotrophs were exposed in medium lacking nutrients essential for growth, nor when the levo form of EMB was used. EMB caused no increase in deoxyribonucleic acid synthesis, nor in septum formation of dividing cells. Treated cells changed morphologically, resulting in a lower surface area-to-volume ratio. Whereas EMB did not eliminate cell clusters, the cluster size decreased markedly as detected by filtration and Coulter counter measurements. We concluded that EMB causes a reduced surface-to-volume ratio, leading to reduced cell cohesion and a consequent reduction in cluster size, reflected in an increase in colony-forming units.

This article has been cited by other articles:

• Bosne-David, S., Barros, V., Verde, S. C., Portugal, C., David, H. L. (2000). Intrinsic resistance of Mycobacterium tuberculosis to clarithromycin is effectively reversed by subinhibitory concentrations of cell wall inhibitors. J Antimicrob Chemother 46: 391-395 [Abstract] [Full Text]  
• Piddock, L. J. V., Williams, K. J., Ricci, V. (2000). Accumulation of rifampicin by Mycobacterium aurum, Mycobacterium smegmatis and Mycobacterium tuberculosis. J Antimicrob Chemother 45: 159-165 [Abstract] [Full Text]