Identification of the Free Carboxyl Groups in Peptides


THE Schlack and Kumpf procedure1 for identifying the amino-acids which provide terminal carboxyl groups in peptides has been made the basis of a micro method which works well with simple peptides and may be of use in studying the free α-carboxyl groups in proteins. In the case of glycylleucine and glycylvaline, the method has been used successfully, although preliminary experiments with insulin and wool keratin have indicated that some modification of the procedure may be necessary before it can be used with proteins.


  1. 1

    Schlack, P., and Kumpf, W., Z. physiol. Chem., 154, 125 (1926).

  2. 2

    Edman, P. (private communication, 1949).

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TIBBS, J. Identification of the Free Carboxyl Groups in Peptides. Nature 168, 910 (1951).

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