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 Danelishvili, L.
Right arrow Articles by Bermudez, L. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Danelishvili, L.
Right arrow Articles by Bermudez, L. E.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, September 2005, p. 3707-3714, Vol. 49, No. 9
0066-4804/05/$08.00+0     doi:10.1128/AAC.49.9.3707-3714.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Genomic Approach to Identifying the Putative Target of and Mechanisms of Resistance to Mefloquine in Mycobacteria

Lia Danelishvili,1,2 Martin Wu,1,2 Lowell S. Young,2 and Luiz E. Bermudez1,2*

Department of Biomedical Sciences, College of Veterinary Medicine, Department of Microbiology, College of Science, Oregon State University, Corvallis, Oregon 97331,1 Kuzell Institute for Arthritis and Infectious Diseases, California Pacific Medical Center Research Institute, San Francisco, California 941152

Received 29 December 2004/ Returned for modification 3 March 2005/ Accepted 18 June 2005

The emergence of mycobacterial resistance to multiple antimicrobials emphasizes the need for new compounds. The antimycobacterial activity of mefloquine has been recently described. Mycobacterium avium, Mycobacterium smegmatis, and Mycobacterium tuberculosis are susceptible to mefloquine in vitro, and activity was evidenced in vivo against M. avium. Attempts to obtain resistant mutants by both in vitro and in vivo selection have failed. To identify mycobacterial genes regulated in response to mefloquine, we employed DNA microarray and green fluorescent protein (GFP) promoter library techniques. Following mefloquine treatment, RNA was harvested from M. tuberculosis H37Rv, labeled with 32P, and hybridized against a DNA array. Exposure to 4x MIC resulted in a significant stress response, while exposure to a subinhibitory concentration of mefloquine triggered the expression of genes coding for enzymes involved in fatty acid synthesis, the metabolic pathway, and transport across the membrane and other proteins of unknown function. Evaluation of gene expression using an M. avium GFP promoter library exposed to subinhibitory concentrations of mefloquine revealed more than threefold upregulation of 24 genes. To complement the microarray results, we constructed an M. avium genomic library under the control of a strong sigma-70 (G13) promoter in M. smegmatis. Resistant clones were selected in 32 µg/ml of mefloquine (wild-type M. avium, M. tuberculosis, and M. smegmatis are inhibited by 8 µg/ml), and the M. avium genes associated with M. smegmatis resistant to mefloquine were sequenced. Two groups of genes were identified: one affecting membrane transport and one gene that apparently is involved in regulation of cellular replication.

* Correspondingauthor. Mailing address: Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, 105 Magruder Hall, Corvallis, OR 97331-8797. Phone: (541) 737-6538. Fax: (541) 737-8035. E-mail: luiz.bermudez{at}oregonstate.edu.

Antimicrobial Agents and Chemotherapy, September 2005, p. 3707-3714, Vol. 49, No. 9
0066-4804/05/$08.00+0     doi:10.1128/AAC.49.9.3707-3714.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Young, L. S. (2009). Reconsidering Some Approved Antimicrobial Agents for Tuberculosis. Antimicrob. Agents Chemother. 53: 4577-4579 [Full Text]  
  • Harriff, M. J., Danelishvili, L., Wu, M., Wilder, C., McNamara, M., Kent, M. L., Bermudez, L. E. (2009). Mycobacterium avium Genes MAV_5138 and MAV_3679 Are Transcriptional Regulators That Play a Role in Invasion of Epithelial Cells, in Part by Their Regulation of CipA, a Putative Surface Protein Interacting with Host Cell Signaling Pathways. J. Bacteriol. 191: 1132-1142 [Abstract] [Full Text]  
  • Bermudez, L. E., Motamedi, N., Chee, C., Baimukanova, G., Kolonoski, P., Inderlied, C., Aralar, P., Wang, G., Phan, L. T., Young, L. S. (2007). EDP-420, a Bicyclolide (Bridged Bicyclic Macrolide), Is Active against Mycobacterium avium. Antimicrob. Agents Chemother. 51: 1666-1670 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»