Question

If you could briefly answer these questions so I can understand. I seem to be stuck on 8-10. But if you could still provide an answer for 6-7 so i can check my answers. Thankyou.

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Answer 1

Q 6 ans:

A plot of the amount of HPRG bound at equilibrium versus pH resembles an acid-base titration curve with human HPRG having a pK _a of 6.8, near that of histidine. An increase in signal due to the specific binding of IgG to HPRG already bound to heparin is observed at pH 6.7 and to a limited extent at, but not above, pH 7.0, in good agreement with the results obtained with the purified system.

Q9 ans:

HPRG treated with excess diethylpyrocarbonate (DEPC) to chemically modify histidine residues does not bind, supporting the importance of histidine in the interaction with heparin.