Structural features of MU1140 and select lead compounds.

<p>Panel (A) depicts the primary amino acid sequence of MU1140. The second generation of MU1140 variants designed in the current study focused on the residues highlighted in gray. Panel (B) depicts the structure of unusual amino acids. Panel (C) tabulates the substitutions of lead compounds carried through <i>in vivo</i> efficacy studies. Legend: amino acids, AA.</p>