Fig. 5.

Hypothetical models of interactions of WT and E540V GyrB with quinolones with substituents at R-7 and R-8. The models show the hydrogen bonding network relationship between residues of the WT and E540V gyrases and the R-7 and R-8 groups of CIP (A). Panels B and C show the relationships of MXF and SIX with the QBP of the DNA GyrB subunit of M. tuberculosis. The left and right panels show the WT and GyrB-E540V gyrase activities for hydrogen interaction with quinolones. Position 540 is indicated by bold type.