Here is a figure that takes advantage of the vertex distruction in Povscript+ (version 2.1.2_1.61)

So here is the script that generates this

     plot
       window 30;
     background white; 
     
     read mol "synt.pdb";
     macro todraw
         either in from A189 to A201
             or in from B189 to B201
     end_macro;

     !For some reason this has to be after the macro
     readmap mymap synt.dn6 covering $todraw plus 2;
     
     transform atom *
         by centre position atom *
         by [snipped rotation and translations]
     ;
     
     set bsurf 0;
     set maptype 0;
     set mapthresh 0.5;
     set linecolour deepskyblue;
     set linewidth .1;
     set mapradius 1.5;
     contour mymap at 1.0 covering $todraw;
     
     set segments 12;
     set atomcolour atom N* mediumblue,
         atomcolour atom O* crimson,
         atomcolour atom S* forestgreen,
         atomcolour atom P* purple,
         atomcolour atom C* gold,
         atomradius atom * .75,
         colourparts on;
     
     ball-and-stick $todraw;
     
     set colourparts off;
     set linecolour black;
     set labeloffset -3 .8 0;
     label require atom NE and in residue A193 "%r";
     [snipped other labels] 
     end_plot

Here is the same figure with mapthresh 1.0 (the default is 0.8).

Here is the equivalent Bobscript Image and Bobscript input file.