Question

4. A certain protein is known to be embedded within a cell membrane. What type of amino acids would you expect this protein to contain on its surface and why? 5. Structural proteins form the basis for hair and nails and have a high cysteine content. Cysteine side groups (-CH2SH) can react with each other to form disulfide bridge. What type of bonding holds the bridge together? Why is this interaction important for the function of structural proteins? Hemoglobin is the protein that transports O2 through the blood. The mutated Hammersmith haemoglobin protein has a phenylalanine monomer (amino acid) where a serine monomer should be. How would this change affect the protein function? 6.

Answer 1

6.

mutated hammersmith hemoglobin is an unstable hemoglobin with low oxygen affinity. it is caused by the single nucleotide substitution. in this condition there is formation of altered heme pockets thereby it decreases the oxygen binding capacity of hemoglobin, and there is also decreased cooperativity( cooperativity means , as oxygen is bound to one subunit , the binding to other subunits is facilitated), as the oxygen affinity of hemoglobin decreases the oxygen binding curve of hemoglobin shifts to the right. there is no conversion of tensed form(T- less oxygen binding affinity) into relaxed form(R- more oxygen binding affinity) .