This Article
Right arrow Abstract Freely available
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 Diallo, K.
Right arrow Articles by Wainberg, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Diallo, K.
Right arrow Articles by Wainberg, M. A.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, July 2003, p. 2376-2379, Vol. 47, No. 7
0066-4804/03/$08.00+0     DOI: 10.1128/AAC.47.7.2376-2379.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

The M184V Substitution in Human Immunodeficiency Virus Type 1 Reverse Transcriptase Delays the Development of Resistance to Amprenavir and Efavirenz in Subtype B and C Clinical Isolates{dagger}

Karidia Diallo,1,2 Bluma Brenner,1 Maureen Oliveira,1 Daniela Moisi,1 Mervi Detorio,1 Matthias Götte,1,2,3 and Mark A. Wainberg1,2,3*

McGill AIDS Centre, Lady Davis Institute-Jewish General Hospital,1 Department of Microbiology and Immunology,2 Department of Experimental Medicine, McGill University, Montreal, H3T 1E2 Quebec, Canada3

Received 14 October 2002/ Returned for modification 23 December 2002/ Accepted 9 April 2003


arrow
ABSTRACT
 
The M184V substitution in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT), encoding high-level resistance to lamivudine (3TC), results in decreased HIV-1 replicative capacity, diminished RT processivity, and increased RT fidelity in biochemical assays. We assessed the effect of M184V on the development of resistance to the nonnucleoside RT inhibitors efavirenz (EFV) and nevirapine, and to the protease inhibitor amprenavir (APV) in tissue culture. Genotypic analysis revealed differences in EFV resistance-conferring mutations in subtype B (K103N) versus subtype C (V106 M), and the appearance of both was significantly delayed in the M184V-containing variants compared with the wild type (WT). Similarly, there was a marked delay in the emergence of mutations associated with APV resistance (I54 M/L/V) in subtype B viruses harboring M184V compared with paired WT viral isolates.


arrow
TEXT
 
The YMDD catalytic domain of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is highly conserved among polymerase enzymes, and mutations within this region have a significant effect on RT catalytic activity (23). The M184V mutation results in high-level resistance to the (-) enantiomer of 2',3'-dideoxy-3'-thiacytidine (3TC) as well as low-level resistance to other nucleoside RT inhibitors (NRTIs), including 2',3'-dideoxycytidine, 2',3'-dideoxyinosine (ddI), and abacavir (2, 6, 8, 20). M184V is also associated with diminished RT processivity and viral replication fitness in primary cells (1, 3, 12, 13, 21) as well as increased RT fidelity, as assessed by deoxynucleotide misincorporation and misinsertion experiments (9, 16, 21).

Interestingly, in vivo studies have revealed that 3TC can continue to exert virological benefit in spite of the M184V mutation (5). The presence of M184V can also result in increased susceptibility to zidovudine (ZDV) and other drugs in vitro (13, 22). In addition, a residual antiviral activity of 3TC may sometimes still be detected in spite of M184V (17), and M184V RT can impair the rescue of ZDV-terminated primers during synthesis of viral DNA (7).

However, other work has shown that exposure of HIV-IIIB-containing M184V to nine different non-NRTIs (NNRTIs) resulted in the rapid emergence of NNRTI-resistant virus and that this occurred at a rate similar to that seen with wild-type (WT) HIV-IIIB (10, 13). We have monitored the evolutionary potential and resistance patterns of M184V-containing versus parental WT variants when grown in the presence of efavirenz (EFV) for both subtypes B and C and amprenavir (APV) for subtype B viruses and found that the variants containing M184V required a longer period of selection (i.e., delays of 10 and 29 weeks, respectively) to develop phenotypic resistance to EFV and APV under conditions in which the genotypic patterns of the WT and M184V-containing variants were similar.

Selection of resistance to EFV by using subtype B and C clinical isolates. HIV-infected subtype B clinical isolates were obtained with informed consent from drug-naïve individuals at our clinics in Montreal, Canada, and subtype C clinical isolates were obtained from treatment-naïve subjects from Ethiopia and Botswana (14). Viral strains were amplified as described by coculture of peripheral blood mononuclear cells from infected patients with uninfected cord blood mononuclear cells (11). Cord blood mononuclear cells were also used to generate 3TC-resistant variants of both of the subtype HIV-1 isolates as described by using a multiplicity of infection of 0.01 (6). Drug susceptibility assays and 50% inhibitory concentrations (IC50) of 3TC were determined by RT assay as described (6, 14); at each passage, cells were collected and kept at -80°C for sequencing. Insofar as drug selections with EFV and APV required 30 to 52 weeks for development of resistance, viruses were maintained in the presence of low concentrations of 3TC (i.e., 0.1 µM) to prevent back-mutation of M184V and overgrowth with WT variants. In the absence of 3TC, M184V-containing viruses reverted to WT within 20 weeks (data not shown). Samples were genotyped by using the Open Gene automated DNA system (Visible Genetics Inc., Toronto, Ontario, Canada). We received 3TC, EFV, and APV as gifts from Shire Biochem. Inc. (Montreal, Canada), Bristol-Myers-Squibb Pharmaceuticals (Montreal, Quebec, Canada), and GlaxoSmithKline (Research Triangle Park, N.C.), respectively.

For all EFV selections, the starting and endpoint concentrations were 0.001 µM and 1 µM, respectively (Fig. 1A). EFV concentrations had to be increased slowly due to marked decreases in RT activity of treated cultures compared with parallel cultures grown in the absence of drug (Fig. 1A), and a WT virus required 30 weeks to become fully resistant to EFV through the acquisition of the K103N mutation compared with 40 weeks in the case of a matched virus containing the M184V substitution (Table 1). In contrast, resistance to NVP (K103N) arose within 10 weeks for both M184V-containing and WT viruses, and the appearance of K103N was necessary for high-level phenotypic resistance to EFV to occur (Table 1). There was a significant delay in time to the first appearance of a mixture of K103N and WT viruses in studies performed with M184V-containing viruses compared with WT (Tables 1 and 2).




View larger version (25K):
[in this window]
[in a new window]
  		FIG. 1. Selection of resistance to drugs in tissue culture. (A) Stepwise progression of EFV concentrations and development of resistance in a paired experiment involving the WT and M184V-containing 4246 clinical isolates of subtype B origin. (B) Selection of resistance to EFV in WT and M184V-containing clinical isolates of subtype C origin. Concentrations of EFV are expressed as changes in mean IC50 values (n-fold). Arrows indicate time to first appearance of V106 M. Values represent the mean ± standard error of the mean (n = 6 and 2 for WT and M184V isolates, respectively). (C) Selection of resistance to APV in WT and M184V-containing clinical isolates of subtype C origin. Concentrations of APV are expressed as changes in mean IC50 values (n-fold). Arrows indicate time to first appearance of the I54L mutation.


View this table:
[in this window]
[in a new window]
  		TABLE 1. Time to development of major and minor mutations associated with resistance to EFV in WT and M184V subtype B isolatesa


View this table:
[in this window]
[in a new window]
  		TABLE 2. Time to selection of phenotypic resistance to APV and EFV using WT versus M184V subtype B and C isolatesa

Subtype C clinical isolates. Resistance to EFV in subtype C viruses arises through the acquisition of a V106 M mutation that also yields high-level cross-resistance to all currently approved NNRTIs (7). EFV resistance through the acquisition of V106 M arose more rapidly in subtype C viruses than in subtype B viruses that acquired the K103N substitution. In addition, the time to appearance of V106 M was delayed by approximately 10 weeks in viruses that also contained M184V compared to WT (Fig. 1B, Table 2). Phenotypic assays showed >50-fold cross-resistance to NNRTIs upon acquisition of V106 M or K103N (4).

Selection of resistance to APV by using subtype B clinical isolates. The B-3350-WT virus and its M184V-containing counterpart were selected for resistance to APV as described above, with RT assays performed on a weekly basis (Fig. 1C). APV concentrations were increased slowly, and no increases in drug concentrations were applied when levels of RT activity were <10% of those of control cultures grown in the absence of drug, since a too-rapid increase in protease inhibitor concentration caused complete viral suppression. A period of >6 months was required for the acquisition of mutations in the viral protease (PR) associated with high-level phenotypic resistance to APV, i.e., I54L/M/V (Fig. 1C, Table 3).


View this table:
[in this window]
[in a new window]
  		TABLE 3. Development of resistance to APV in WT and M184V clade B isolatesa

Genotypic results comparing paired WT and M184V viruses show that 24 weeks were required for an initial emergence of phenotypic resistance to APV in WT viruses (Tables 2 and 3). This was delayed by >19 weeks for the M184V variants compared to WT, under conditions in which only very low concentrations of APV, i.e., <0.1 µM, were present for over 22 weeks (Fig. 1C, Table 3).

There was also a lag in regard to appearance of the major I54 M/V/L mutations associated with resistance to APV (Table 3) in the M184V variants versus WT. Phenotypic analysis revealed that acquisition of the I54V/L/M mutations conferred >50-fold resistance to APV as well as cross-resistance to indinavir and nelfinavir (data not shown). In addition to I54 M/V/L, other accessory mutations, i.e., V32I and M46I, were also present. Selections of subtype C viruses with APV have been in progress for over 1 year. We have not yet succeeded in documenting resistance to APV using either WT subtype C viruses or subtype C viruses containing the M184V substitution in RT.

Our study was designed to determine the impact of the M184V mutation in RT on the development of resistance to EFV and APV as drugs representative of NNRTIs and protease inhibitors, respectively. Overall, our data are in agreement with previously published data on the evolutionary potential of viruses harboring the M184V mutation (12), i.e., M184V attenuated the emergence of resistance to EFV in subtype B and C infections as well as resistance to APV in subtype B viruses. While these data appear to conflict with earlier findings that M184V viruses were not delayed in the development of resistance to NNRTIs (10), it is noteworthy that EFV resistance develops more slowly than that to NVP and delavirdine (DLV), and it was only NVP and not EFV that had previously been assessed (18, 19). Moreover, our study employed clinical isolates and primary cells compared with recombinant viruses and cell lines. In this regard, it should be noted that the lower fitness of M184V-containing viruses is more pronounced in primary cells than in cell lines (1, 13). Similar results were obtained in regard to the slower appearance of the I54L/M/V mutations in M184V variants of subtype B viruses that were selected with APV.

It has been demonstrated that a single-cycle recombinant assay can yield increased mutational rates of RTs resistant to ZDV in the presence of each of ZDV and 3TC (15). However, recombinant single-cycle assays do not take into account the cumulative effects of M184V on HIV-1 replicative rates, the ability of HIV-1 to initiate new rounds of infection, or the accumulation of mutations that may require months or even years to develop either in vivo or in cell culture.

Overall, our results demonstrate that the low replicative fitness of HIV-1 variants that contain M184V can delay the occurrence of resistance to at least some antiviral drugs, notably APV and EFV, in primary cells.

Nucleotide accession numbers. Accession numbers for the clinical isolates used in this study are as follows: 3350 (PR-AY236362; RT AY236363), 5346 (PR-AY236360; RT-AY236361), 4246 (PR-AY213138; RT-AY213139). Accession numbers for the subtype C isolates have already been designated (21).

(This work was performed by Karidia Diallo in partial fulfillment of the requirements for a Ph.D. degree, faculty of Graduate Studies and Research, McGill University, Montreal, Quebec, Canada.)


arrow
ACKNOWLEDGMENTS
 
This work was supported by grants from the Canadian Institutes of Health Research and by a donation from Aldo and Diane Bensadoun.


arrow
FOOTNOTES
 
* Corresponding author. Mailing address: McGill AIDS Centre, Lady Davis Institute-Jewish General Hospital, 3755 Cote Ste-Catherine Rd., Montréal, Québec, Canada, H3T 1E2. Phone: (514) 340-8260. Fax: (514) 340-7537. E-mail: mark.wainberg{at}mcgill.ca. Back

{dagger} Dedicated to the memory of James-Paul Marois. Back


arrow
REFERENCES
 
    1
  1. Back, N. K. T., M. Nijhuis, W. Keulen, C. A. B. Boucher, B. B. O. Essnik, A. B. P. van Kuilenburg, A. H. van Gennip, and B. Berkhout. 1996. Reduced replication of 3TC-resistant HIV-l variants in primary cells due to a processivity defect of the reverse transcriptase enzyme. EMBO J. 15:4040-4049.[Medline]
    2. 2
  2. Boucher, C. A. B., N. Cammack, P. Schipper, R. Schuurman, P. L. Rouse, and J. M. Cameron. 1993. High level resistance to (-) enantiomeric 2'-deoxy-3'-thiacytidine (3TC) in vitro is due to one amino acid substitution in the catalytic site of human immunodeficiency virus type 1 reverse transcriptase. Antimicrob. Agents Chemother. 37:2231-2234.[Abstract/Free Full Text]
    3. 3
  3. Brenner, B. G., J. P. Routy, M. Petrella, D. Moisi, M. Oliveira, M. Deterio, B. Spira, V. Essabag, B. Conway, R. Lalonde, R. P. Sekaly, and M. A. Wainberg. 2002. Persistence and fitness of multidrug-resistant human immunodeficiency virus type 1 acquired in primary infection. J. Virol. 76:1753-1761.[Abstract/Free Full Text]
    4. 4
  4. Brenner, B. G., D. Turner, M. Oliveira., D. Moisi, M. Detorio, M. Carobene, R. G. Marlink, J. Schapiro, M. Roger, and M. A. Wainberg. 2003. A V106M mutation in HIV-1 clade C viruses exposed to efavirenz confers cross-resistance to non-nucleoside reverse transcriptase inhibitors. AIDS 17:F1-F5.[CrossRef][Medline]
    5. 5
  5. Eron, J. J., S. L. Benoit, J. Jemsek, R. D. MacArthur, J. Santana, J. B. Quinn, D. R. Kuritzkes, M. A. Fallon, and M. Rubin. 1995. Treatment with lamivudine, zidovudine, or both in HIV-positive patients with 200 to 500 CD4+ cells per cubic millimeter. North American HIV Working Party. N. Engl. J. Med. 333:1662-1669.[Abstract/Free Full Text]
    6. 6
  6. Gao, Q., Z. Gu, M. A. Paniak, J. Cameron, N. Cammack, C. Boucher, and M. A. Wainberg. 1993. The same mutation that encodes low-level human immunodeficiency virus type 1 resistance to 2',3'-dideoxyinosine and 2',3'-dideoxycytidine confers high-level resistance to the (-) enantiomer of 2',3'-dideoxy-3'-thiacytidine. Antimicrob. Agents Chemother. 37:1390-1392.[Abstract/Free Full Text]
    7. 7
  7. Götte, M., D. Arion, M. A. Parniak, and M. A. Wainberg. 2000. The M184V mutation in the reverse transcriptase of human immunodeficiency virus type 1 impairs rescue of chain-terminated DNA synthesis J. Virol. 74:3579-3585.[Abstract/Free Full Text]
    8. 8
  8. Gu, Z., Q. Gao, X. Li, M. A. Parniak, and M. A. Wainberg. 1992. Novel mutation in the human immunodeficiency virus type 1 reverse transcriptase gene that encodes cross-resistance to 2',3'-dideoxyinosine and 2',3'-dideoxycytidine. J. Virol. 66:7128-7135.[Abstract/Free Full Text]
    9. 9
  9. Hsu, M., P. Inouye, L. Rezende, N. Richard, Z. Li, V. R. Prasad, and M. A. Wainberg. 1997. Higher fidelity of RNA-dependent DNA mispair extension by M184V drug-resistant than wild-type reverse transcriptase of human immunodeficiency virus type 1. Nucleic Acids Res. 25:4532-4536.[Abstract/Free Full Text]
    10. 10
  10. Jonckheere, H., M. Witvrouw, E. De Clercq, and J. Anné. 1998. Lamivudine resistance of HIV type 1 does not delay development of resistance to nonnucleoside HIV type 1-specific reverse transcriptase inhibitors as compared with wild-type HIV type 1. AIDS Res. Hum. Retrovir. 14:249-253.[Medline]
    11. 11
  11. Keulen, W., N. K. Back, A. van Wijk, C. A. Boucher, and B. Berkhout. 1997. Initial appearance of the 184Ile variant in lamivudine-treated patients is caused by the mutational bias of human immunodeficiency virus type l reverse transcriptase J. Virol. 71:3346-3350.[Abstract]
    12. 12
  12. Keulen, W., A. van Wijk, R. Schuurman, B. Berkhout, and C. A. B. Boucher. 1999. Increased polymerase fidelity of lamivudine-resistant HIV-1 variants does not limit their evolutionary potential. AIDS 13:1343-1349.[CrossRef][Medline]
    13. 13
  13. Larder, B. A., S. D. Kemp, and P. R. Harrigan. 1995. Potential mechanism for sustained antiretroviral efficacy of AZT-3TC combination therapy. Science 269:696-699.[Abstract/Free Full Text]
    14. 14
  14. Loemba, H., B. Brenner, M. A. Parniak, S. Ma'ayan, S. B. Spira, D. Moisi, M. Oliveira, M. Deterio, and M. A. Wainberg. 2002. Genetic divergence of human immunodeficiency virus type 1 Ethiopian clade C reverse transcriptase (RT) and rapid development of resistance against nonnucleoside inhibitors of RT. Antimicrob. Agents Chemother. 46:2087-2094.[Abstract/Free Full Text]
    15. 15
  15. Mansky, L. M., D. K. Pearl, and L. C. Gajary. 2002. Combination of drugs and drug-resistant reverse transcriptase results in a multiplicative increase of human immunodeficiency virus type 1 mutant frequencies. J. Virol. 76:9253-9259.[Abstract/Free Full Text]
    16. 16
  16. Pandey, V., N. Kaushik, N. Rege, S. G. Sarafianos, P. N. S. Yadav, and M. J. Modal. 1996. Role of methionine 184 of human immunodeficiency virus type-1 reverse transcriptase in the polymerase function and fidelity of DNA synthesis. Biochemistry 35:2168-2179.[CrossRef][Medline]
    17. 17
  17. Quan, Y., B. G. Brenner, M. Oliveira, and M. A. Wainberg 2003. Lamivudine can exert a modest antiviral effect against human immunodeficiency virus type 1 containing the M184V mutation. Antimicrobial Agents Chemother. 47:747-754.[Abstract/Free Full Text]
    18. 18
  18. Richman, D. D., C. K. Shih, I. Lowy, J. Rose, P. Prodanovich, S. Goff, and J. Griffin. 1991. Human immunodeficiency virus type 1 mutants resistant to non-nucleoside inhibitors of reverse transcriptase arise in cell culture. Proc. Natl. Acad. Sci. USA 88:11241-11245.[Abstract/Free Full Text]
    19. 19
  19. Shulman, N., A. R. Zolopa, D. Passaro, R. W. Shafer, W. Huang, D. Katzenstein, D. M. Israelski, N. Hellman, C. Petropoulos, and J. Witcomb. 2001. Phenotypic hypersusceptibility to non-nucleoside reverse transcriptase inhibitors in treatment-experienced HIV-infected patients: impact on virological response to efavirenz-based therapy. AIDS 15:1125-1132.[CrossRef][Medline]
    20. 20
  20. Tisdale, M., S. D. Kemp, N. R. Parry, and B. A. Larder. 1993. Rapid in vitro selection of human immunodeficiency virus type 1 resistant to 3'-thiacytidine inhibitors due to a mutation in the YMDD region of reverse transcriptase. Proc. Natl. Acad. Sci. USA 90:5653-5656.[Abstract/Free Full Text]
    21. 21
  21. Wainberg, M. A., W. C. Drosopoulos, H. Salomon, M. Hsu, G. Borkow, M. A. Parniak, Z. Gu., Q. Song, J. Manne, S. Islam, G. Castriota, and V. R. Prasad. 1996. Enhanced fidelity of 3TC-selected mutant HIV-1 reverse transcriptase. Science 217:1282-1285.[CrossRef]
    22. 22
  22. Wainberg, M. A., D. M. Miller, Y. Quan, H. Salomon, A. S. Mulato, P. D. Lamy, N. A. Margot, K. E. Anton, and J. M. Cherrington. 1999. In vitro selection and characterization of HIV-1 with reduced susceptibility to PMPA. Antiviral Ther. 4:87-94.[Medline]
    23. 23
  23. Wakefield, J. K., S. A. Jablonski, and C. D. Morrow. 1992. In vitro enzymatic activity of human immunodeficiency virus type 1 reverse transcriptase mutants in the highly conserved YMDD amino acid motif correlates with the infectious potential of the proviral genome. J. Virol. 66:6806-6812.[Abstract/Free Full Text]

Antimicrobial Agents and Chemotherapy, July 2003, p. 2376-2379, Vol. 47, No. 7
0066-4804/03/$08.00+0     DOI: 10.1128/AAC.47.7.2376-2379.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Ntemgwa, M. L., Toni, T. d., Brenner, B. G., Camacho, R. J., Wainberg, M. A. (2009). Antiretroviral Drug Resistance in Human Immunodeficiency Virus Type 2. Antimicrob. Agents Chemother. 53: 3611-3619 [Full Text]  
  • Knoepfel, S. A., Salisch, N. C., Huelsmann, P. M., Rauch, P., Walter, H., Metzner, K. J. (2008). Comparison of G-to-A Mutation Frequencies Induced by APOBEC3 Proteins in H9 Cells and Peripheral Blood Mononuclear Cells in the Context of Impaired Processivities of Drug-Resistant Human Immunodeficiency Virus Type 1 Reverse Transcriptase Variants. J. Virol. 82: 6536-6545 [Abstract] [Full Text]  
  • Ntemgwa, M., Brenner, B. G., Oliveira, M., Moisi, D., Wainberg, M. A. (2007). Natural Polymorphisms in the Human Immunodeficiency Virus Type 2 Protease Can Accelerate Time to Development of Resistance to Protease Inhibitors. Antimicrob. Agents Chemother. 51: 604-610 [Abstract] [Full Text]  
  • Doualla-Bell, F., Avalos, A., Gaolathe, T., Mine, M., Gaseitsiwe, S., Ndwapi, N., Novitsky, V. A., Brenner, B., Oliveira, M., Moisi, D., Moffat, H., Thior, I., Essex, M., Wainberg, M. A. (2006). Impact of human immunodeficiency virus type 1 subtype C on drug resistance mutations in patients from botswana failing a nelfinavir-containing regimen.. Antimicrob. Agents Chemother. 50: 2210-2213 [Abstract] [Full Text]  
  • Siddappa, N. B., Dash, P. K., Mahadevan, A., Jayasuryan, N., Hu, F., Dice, B., Keefe, R., Satish, K. S., Satish, B., Sreekanthan, K., Chatterjee, R., Venu, K., Satishchandra, P., Ravi, V., Shankar, S. K., Shankarappa, R., Ranga, U. (2004). Identification of Subtype C Human Immunodeficiency Virus Type 1 by Subtype-Specific PCR and Its Use in the Characterization of Viruses Circulating in the Southern Parts of India. J. Clin. Microbiol. 42: 2742-2751 [Abstract] [Full Text]  
  • Turner, D., Brenner, B., Wainberg, M. A. (2003). Multiple Effects of the M184V Resistance Mutation in the Reverse Transcriptase of Human Immunodeficiency Virus Type 1. CVI 10: 979-981 [Full Text]  

This Article
Right arrow Abstract Freely available
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 Diallo, K.
Right arrow Articles by Wainberg, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Diallo, K.
Right arrow Articles by Wainberg, M. A.

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