Conjugated protein

A conjugated protein is a protein that functions in interaction with other (non-polypeptide) chemical groups attached by covalent bonding or weak interactions.[1]

Conjugated protein - hemoglobin: 4 subunits are in different colours
Heme — prosthetic group of hemoglobin

Many proteins contain only amino acids and no other chemical groups, and they are called simple proteins. However, other kind of proteins yield, on hydrolysis, some other chemical component in addition to amino acids and they are called conjugated proteins. The non-amino part of a conjugated protein is usually called its prosthetic group. Most prosthetic groups are formed from vitamins. Conjugated proteins are classified on the basis of the chemical nature of their prosthetic groups.

Examples

Some examples of conjugated proteins are lipoproteins, glycoproteins, phosphoproteins, hemoproteins, flavoproteins, metalloproteins, phytochromes, cytochromes, opsins and chromoproteins.

Hemoglobin contains the prosthetic group known as heme. Each heme group contains an iron ion (Fe2+) which forms a co-ordinate bond with an oxygen molecule (O2), allowing hemoglobin to transport oxygen through the bloodstream. As each of the four protein subunits of hemoglobin possesses its own prosthetic heme group, each hemoglobin can transport four molecules of oxygen.

Glycoproteins are generally the largest and most abundant group of conjugated proteins. They range from glycoproteins in cell surface membranes that constitute the glycocalyx, to important antibodies produced by leukocytes.

gollark: It's not as if original-me would *suffer* at all if they were instantly disintegrated, so I don't particularly care.
gollark: I think that as long as teleportation was shown to be safe the ethical/philosophical issues would be outweighed by practicality pretty fast. I personally don't care about the continuity thing, however that's meant to work.
gollark: Not really the philosophy side, more "you can duplicate people" and "you can duplicate *things*".
gollark: They never consider the implications of that sort of replicator/teleporter technology.
gollark: Though I might be a bit worried about it since it *might* randomly disintegrate me or something if there's a bug in the reassembly bit.

References
  1. Lehninger: Principles of Biochemistry (4th ed.). New York, New York: W. H. Freeman and Company.
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