The gene encoding P27 lipoprotein and a putative antibiotic-resistance gene form an operon in Mycobacterium tuberculosis and Mycobacterium bovis

Instituto de Biotecnología 1 and Instituto de Patobiología 2 , CICV-INTA, PO Box 77, Castelar, Argentina Author for correspondence: A. Cataldi. Tel: +54 11 4621 0199. Fax: +54 11 4481 2975. e-mail: acataldi{at}inta.gov.ar P27 is an antigenic membrane lipoprotein synthesized by members of the Mycobacterium tuberculosis complex. Northern blotting and RT-PCR experiments indicated that the genes encoding P27 and a putative antibiotic transporter (P55) form an operon. A promoter region was identified and characterized by deletion analysis in Mycobacterium smegmatis . Two transcription initiation points were mapped in Mycobacterium bovis BCG by primer extension analysis to 76 bp and 87 bp upstream of the ATG initiation codon. Putative -10 and -35 promoter consensus sequences associated with these showed 66% similarity to previously identified mycobacterial promoters. These results suggest that the P27 / P55 operon is transcribed from two promoters in M. bovis BCG. Keywords: Mycobacterium tuberculosis , Mycobacterium bovis , promoter, operon, lipoprotein