Reaction of beta-propiolactone with amino acids and its specificity for methionine.
1. The reactions of beta-propiolactone with amino acids were investigated under various conditions of pH and temperature to find those under which the reagent acted with specificity. 2. At pH9.0 and 22 degrees , after 15min. of reaction, at least 85% of each amino acid had reacted, methionine and cystine being the most reactive. 3. At pH7.0 and 22 degrees most amino acids reacted; methionine, cystine and histidine reacted almost entirely, and proline and lysine to a significantly smaller extent. 4. At pH3.0 and 22 degrees further specificity was obtained; methionine and cystine were the only reactive amino acids. 5. Reaction at pH3.0 and 0 degrees was specific for methionine; it was the only amino acid modified even after 145hr. of reaction.
D000596:Amino Acids; D001322:Autoanalysis; D055598:Chemical Phenomena; D002621:Chemistry; D003080:Cold Temperature; D003553:Cystine; D006639:Histidine; D006863:Hydrogen-Ion Concentration; D007532:Isoleucine; D007783:Lactones; D007930:Leucine; D008239:Lysine; D008715:Methionine; D010649:Phenylalanine; D011392:Proline; D014443:Tyrosine
D000596:Amino Acids; D007783:Lactones; D007532:Isoleucine; D014443:Tyrosine; D010649:Phenylalanine; D003553:Cystine; D006639:Histidine; D011392:Proline; D008715:Methionine; D007930:Leucine; D008239:Lysine