HOMEWORK 3
BIOL/CHEM 5310
due Tuesday, September 17, 2002

1. VVP text, Chapter 5, page 122, problems 1, 6, 8, 9, 12.

2. Calculate the pI of Arg

3. Calculate the net charge of cysteine at pH 8.0

4. Determine which of the following polypeptides would best be purified at neutral pH using DEAE ion exchange chromatography:

a) A-D-L-T-Y-K-E-V-N-R-W-H-F-S-G-T-S

b) L-S-F-Y-D-H-M-P-E-N-T-D-F-M-E-C-Q

c) G-M-K-K-A-G-N-P-Q-W-R-H-F-M-R-S

5. Calculate the ionic strength of the following buffers:

a) .1 M Tris-Cl, pH 7.5

b) .1 M Na-phosphate, pH 7.5

Last updated Tuesday, September 10, 2002

Comments/questions: svik@mail.smu.edu

Copyright 2002, Steven B. Vik, Southern Methodist University