Simulated effect of <i>PP</i>_<i>II</i> propensities on coil <i>R</i>_<i>h</i>.

<p>Each circle and square represents a simulated disordered polypeptide. Squares are from ensembles simulated with position-specific <i>PP</i>_<i>II</i> propensities assigned randomly; circles had <i>PP</i>_<i>II</i> propensity assignments that followed the sequence patterns described in the text. In panel <b>A</b>, <i>f</i>_{<i>PPII</i>,<i>chain</i>} was calculated as <<i>N</i>_<i>PPII</i>>/<i>N</i>, where <<i>N</i>_<i>PPII</i>> was the ensemble averaged number of residues with (Φ,Ψ) in the <i>PP</i>_<i>II</i> region (-75±10, 145±10), and <i>v</i> was calculated as ln(<i>R</i>_<i>h</i>/<i>R</i>_<i>o</i>)/ln(<i>N</i>) using <<i>L</i>>/2 for <i>R</i>_<i>h</i> and 2.16 Å for <i>R</i>_<i>o</i>. These data were fit to <i>v</i> = <i>v</i>_<i>o</i> + <i>β</i>∙ln(1-<i>f</i>_{<i>PPII</i>,<i>chain</i>}), with <i>v</i>_<i>o</i> and <i>β</i> as fit parameters, producing the solid line. In panel <b>B</b>, <i>R</i>_{<i>h</i>,<i>HSC</i>} was calculated as <<i>L</i>>/2. <i>R</i>_{<i>h</i>,<i>fit</i>} was determined from <i>f</i>_{<i>PPII</i>,<i>chain</i>} using <i>R</i>_{<i>h</i>,<i>fit</i>} = (2.16 Å)∙<i>N</i>^<i>v</i> and the panel A fit for <i>v</i>. <i>R</i>_{<i>h</i>,<i>HSC</i>} and <i>R</i>_{<i>h</i>,<i>fit</i>} correlation (R²) is provided in the figure.