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<DIV><SPAN class=471153908-15042008><FONT face=Arial size=2>I am dealing with
antiparallel alpha helices in helix bundles. It would be very useful to be able
to show the polarity of each helix in ribbon display by adding an arrowhead to
the C-terminal end. This is the default for beta strands. Is it possible to
add such an arrowhead in Chimera?</FONT></SPAN></DIV>
<DIV><SPAN class=471153908-15042008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=471153908-15042008><FONT face=Arial size=2>A clunky workaround
that occurs to me is to designate the last residue of each helix as beta
structure. Has anyone tried this: does it work?</FONT></SPAN></DIV>
<DIV><SPAN class=471153908-15042008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=471153908-15042008><FONT face=Arial
size=2>Thanks,</FONT></SPAN></DIV>
<DIV><SPAN class=471153908-15042008><FONT face=Arial size=2>Peter
Knight</FONT></SPAN></DIV>
<DIV><SPAN class=471153908-15042008><FONT face=Arial size=2>University of Leeds,
UK</FONT></SPAN></DIV></BODY></HTML>