Polypeptide folding Poly

Homology to immunoglobulin units is often weak whilst /3-strand patterns are suggestive of V units, only Thy-1. the membrane-distal unit of MRC OX-2 and the poly-immunoglobulin receptor units possess the extra hairpin loop (C /C") which is characteristic of V units (Fig. 11). Thus, the polypeptide chain may fold in a similar way to C units. Although all these molecules are believed to exist as monomers, in most cases the possibility of homodimeric associations has not been ex-... 

Shifts and certain splitting by resonance interactions of amide I and amide II bands in polypeptides in folded and extended conformation are discussed in Ref. 22 and in the early investigations of Miyazawa and of Elkan R. Blout [23], who used IR spectra for the characterization of the conformation of poly-amino acids. 

The number of folds of the polypeptide chains depends upon the nature of the polypeptide block the polyCe-carbobenzoxy-L-lysine) chains are less folded than the poly(y-benzyl-L-glutamate) chains. ... 

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