Q2) The αβα sandwich are tightly packed together and are separated by a large interface from another subunit. Each domain contains several beta sheets in between anywhere between two to four alpha helices.
Q3) Most of the β sheets are parallel, although there are a few antiparallel beta stands in the large domains. The α helices are located on either side of the beta sheets and are fairly close together on either site.
Q4) The α helices and the β strands are connected by loops made of amino acids.
Q5) There is a significant amount of space, and thus a large interface between the subunits that form dimers. The interface consists of a few loops and a few protruding amino acid side chains.
Q6) The interface between subunits probably contains the binding site for activators and inhibitors.
Q7) Since most of the effector molecules have negatively charged atoms (such as ADP with the negatively charged oxygen atoms on the phosphate groups), it is likely that positively charged residues will need to bind to them. Since many basic amino acids have side chains that are positive under cellular conditions, it is likely that basic amino acids will bind to these …show more content…
In addition, both proteins have one large interface between subunits and one smaller interface between them. The subunits of both proteins are in fact made of domains, however, the types of domain differ. Furthermore, the secondary structure of hemoglobin consists of only alpha helices, while that of phosphofructokinase consists of both alpha helices and beta sheets. Furthermore, these two proteins also share their ability for allosteric binding and cooperativity in the protein caused by the binding of the