3 DIFFERENT PUTATIVE PHOSPHATE-TRANSPORT RECEPTORS ARE ENCODED BY THEMYCOBACTERIUM-TUBERCULOSIS GENOME AND ARE PRESENT AT THE SURFACE OF MYCOBACTERIUM-BOVIS BCG

LEFEVRE P BRAIBANT M DEWIT L KALAI M ROEPER D GROTZINGER J DELVILLE JP PEIRS P OOMS J HUYGEN K CONTENT J

P. Lefevre et al., 3 DIFFERENT PUTATIVE PHOSPHATE-TRANSPORT RECEPTORS ARE ENCODED BY THEMYCOBACTERIUM-TUBERCULOSIS GENOME AND ARE PRESENT AT THE SURFACE OF MYCOBACTERIUM-BOVIS BCG, Journal of bacteriology, 179(9), 1997, pp. 2900-2906

53

INGLESE

Article

Microbiology

Journal of bacteriology → ACNP

0021-9193

179

9

1997

2900 - 2906

ISI

0021-9193(1997)179:9<2900:3DPPRA>2.0.ZU;2-W

A gene encoding a protein homologous to the periplasmic ARC phosphate binding receptor PstS from Escherichia coli was cloned and sequenced f rom a lambda gt11 library of Mycobacterium tuberculosis by screening w ith monoclonal antibody 2A1-2, Its degree of similarity to the E. coli PstS is comparable to those of the previously described dl, tuberculo sis phosphate binding protein pab (Ag78, Ag5, or 38-kDa protein) and a nother M. tuberculosis protein which we identified recently, We sugges t that the three nl. tuberculosis proteins share a similar function an d could be named PstS-1, PstS-2, and PstS-3, respectively, Molecular m odeling of their three-dimensional structures using the structure of t he E. coli PstS as a template and their inducibility by phosphate star vation support this view., Recombinant PstS-2 and PstS-3 were produced and purified by affinity chromatography. With PstS-1, these proteins were used to demonstrate the specificity of three groups of monoclonal antibodies. Using these antibodies in flow cytometry and immunoblotti ng analyses, me demonstrate that the three genes are expressed and the ir protein products are present and accessible at tile mycobacterial s urface as well as in its culture filtrate, Together with the M. tuberc ulosis genes encoding homologs of the PstA, PstB, and PstC components we cloned before, the present data suggest that at least one, and poss ibly several, related and functional ABC phosphate transporters exist in mycobacteria. It, is hypothesized that the mycobacterial gene dupli cations presented here may be a subtle adaptation of intracellular pat hogens to phosphate starvation in their alternating growth environment s.