John Sjöquist

Determination of amino acids as phenyl thiohydantoin derivatives. III. Quantitative determination of 3-phenyl-2-thiohydantoins from paper chromatograms.

Abstract A method for quantitative determination of the 3-phenyl- 2 -thiohydantoin derivatives (PTH) from the naturally occuring amino acids is described. The PTHs are synthesized by a micro synthetic procedure from protein hydrolysates (0.5-1 mg protein) and separated on paper chromatograms. The spots are located with the aid of fluorescent screen and eluted from the paper with ethanol. The quantitative calculations are based on the optical density at 269 and 320 mμ of the ethanolic eluates.

Quantitative determination of N-terminal amino acids in some serum proteins.

Abstract A method for quantitative determination of N-terminal amino acids of proteins is described. Results obtained from different serum protein fractions are given and compared with published data.

SEPARATION OF NORMAL HUMAN TRANSFERRIN INTO TWO FRACTIONS.

Abstract Ethanol-fractionated human transferrin (transferrin CC) separates into two fractions when subjected to chromatography on anion-exchange cellulose (CM-cellulose). The two fractions show similarities in their immunological, biological and physical properties. Some differences in their carbohydrate composition are demonstrated. The same separation pattern of transferrin is found if whole serum from individual donors is subjected to the same chromatographic procedure.