1. Mycobacteriology Research Laboratory, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA, Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA, Forschungsinstitut Borstel, Borstel, Germany, Department of Pharmacology and Experimental Therapeutics, The Johns Hopkins University School of Medicine, Baltimore, MD, USA, Department of Chemistry and Biochemistry, University of Maryland, Baltimore, MD, USA