Abstract
An improved freeze-drying method for the study of hydrogen exchange of proteins and polypeptides has been developed. Tritiated water is added to a solution of the exchanging substance to start exchange. Samples are taken at various times and frozen at a low temperature followed by freeze-drying and high-vacuum drying. The tritium-containing dry substance is then dissolved in water and liquid scintillation counted.
Experimental artifacts due to exchange between the substance and ice or the substance and water vapor have been eliminated. Absence of artifacts was demonstrated by control experiments. The exchange curve of poly-dl-alanine at 0° and pH 3.50 was studied. All of the peptide hydrogens exchange at the same rate, in agreement with previous infrared and gel filtration studies.
Original language | American English |
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Journal | Analytical Biochemistry |
Volume | 33 |
DOIs | |
State | Published - Jan 1 1970 |
Externally published | Yes |
Disciplines
- Life Sciences