#1) a) The pK1, pK2, and pKR for the amino acid histidine are 1.8, 9.3, and…

Homework Help Question & Answers

#1) a) The pK1, pK2, and pKR for the amino acid histidine are 1.8, 9.3, and…

#1)

a) The pK1, pK2, and pKR for the amino acid histidine are 1.8, 9.3, and 6.0, respectively. At pH 4.0 would be charged predominantly as follows:

A

a-carboxylate 0, a-amino +1, imidazole +1, net charge +2

B

a-carboxylate +1, a-amino +1, imidazole −1, net charge +1

C

a-carboxylate −1, a-amino +1, imidazole 0, net charge 0

D

a-carboxylate +1, a-amino 0, imidazole −1, net charge 0

E

a-carboxylate −1, a-amino +1, imidazole +1, net charge +1

b) The pK1, pK2, and pKR for the amino acid arginine are 1.8, 9.0, and 12.5, respectively. At pH 7.0 arginine would be charged predominantly as follows:

A

a-carboxylate +1, a-amino 0, guanidino -1, net charge 0

B

a-carboxylate 0, a-amino 0, guanidino +1, net charge +1

C

a-carboxylate −1, a-amino +1, guanidino +1, net charge +1

D

a-carboxylate −1, a-amino 0, guanidino +1, net charge 0

E

a-carboxylate +1, a-amino −1, guanidino −1, net charge −1

c) The pK1, pK2, and pKR for the amino acid aspartic acid are 2.0, 9.9, and 3.9, respectively. At pH 7.0, aspartic acid would be charged predominantly as follows:

A

a-carboxylate +1, a-amino +1, b-carboxylate +1, net charge +3

B

a-carboxylate 0, a-amino +1, b-carboxylate 0, net charge +1

C

a-carboxylate 0, a-amino −1, b-carboxylate 0, net charge −1

D

a-carboxylate +1, a-amino −1, b-carboxylate +1, net charge +1

E

a-carboxylate −1, a-amino +1, b-carboxylate −1, net charge −1

0 0
Add a comment

GET HELP WITH YOUR PAPERS

GET THIS ANSWER FROM EXPERTS NOW

WhatsApp
Hello! Need help with your assignments? We are here
Don`t copy text!