The pK1, pK2, and pKR for the amino acid cysteine are 1.9, 10.7, and 8.4, respectively. At pH 5.0, cysteine would be charged predominantly as follows: alpha-carboxylate –1, alpha-amino +1, sulfhydryl +1, net charge +1 alpha-carboxylate –1, alpha-amino +1, sulfhydryl 0, net charge 0 alpha-carboxylate +1, alpha-amino –1, sulfhydryl –1, net charge -1 alpha-carboxylate 0, alpha-amino 0, sulfhydryl 0, net charge 0 alpha-carboxylate +1, alpha-amino –1, sulfhydryl 0, net charge 0 O O O O O

The pK1, pK2, and pKR for the amino acid cysteine are 1.9, 10.7, and 8.4, respectively. At pH 5.0, cysteine would be charged predominantly as follows: alpha-carboxylate –1, alpha-amino +1, sulfhydryl +1, net charge +1 alpha-carboxylate –1, alpha-amino +1, sulfhydryl 0, net charge 0 alpha-carboxylate +1, alpha-amino –1, sulfhydryl –1, net charge -1 alpha-carboxylate 0, alpha-amino 0, sulfhydryl 0, net charge 0 alpha-carboxylate +1, alpha-amino –1, sulfhydryl 0, net charge 0 O O O O O

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter23: Organic Polymers, Natural And Synthetic

Section: Chapter Questions

Problem 29QAP: For alanine, Ka1=5.1105,Ka2=1.81010 . Calculate the ratios [Z]/[C+] and [Z]/[A+] at pH (a) 2.00. (b)...

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