1. TB Center, Public Health Research Institute,1 and
2. UFR de Biochimie, Université Paris 7, 75251 Paris Cedex 05, France2;
3. Department of Microbiology, New York University Medical Center,3 New York, New York 10016;
4. Department of Microbiology and Immunology, Howard Hughes Medical Institute, Albert Einstein College of Medicine, Bronx, New York 104614;
5. Section of Gene Structure and Regulation, Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 208925; and
6. Department of Microbiology, University of Colorado Health Sciences Center, Denver, Colorado 802626