porphyrin ligand in biological example

[Kaylee Nezwek 1D]

from dr. lavelles lecture on 11/30, he explained how Fe bound to a porphyrin ligand creates a heme complex and how a heme complex plus a protein makes myoglobin, which transports O2 in muscle cells. however, I'm still having a bit of trouble understanding the process, specifically what exactly the heme complex is, how the protein comes into play, and iron's role in helping to transport O2. would anyone be able to explain this process in simpler terms? (sorry if this is a vague question, since I don't really understand its hard for me to know what to ask lol)

[KatarinaReid_3H]

Porphyrin is a tetradentate ligand. This binds to the central Fe transition metal. This whole complex/coordination compound is called a heme complex. The Fe can have a coordination up to 6 and right now only 2 are left unfilled. Thus, histidine an amino acid can bind to the central Fe and an O2 can also bind to the Fe. The Fe takes on an octahedral structure. This whole thing is called myoglobin and it transports oxygen to the muscle tissues inside your body. When 4 myoglobins attach together, this is called hemoglobin and it carries 4O2 or 8 oxygen atoms altogether. The hemoglobin travels in your blood stream delivering oxygen.

[Kaylee Nezwek 1D]

omg thank you so much this was extremely helpful

[Karen Elrayes 1L]

I was literally about to come and ask that exact question. Thank you for the explanation!