Is hemoglobin the only oxygen-binding protein in the human body?

Question

Is hemoglobin the only oxygen-binding protein in the human body?

Answer 1

Obviously not.  Hemoglobin carries oxygen for use by other proteins, most critically in cellular respiration.

Oxidases are proteins that require O2.  While they don't carry O2 the way hemoglobin does, they still bind to it, catalyzing a reaction.

Answer 2

No. Myoglobin is in the muscle tissue of many vertebrates, including humans, it gives muscle tissue a distinct red or dark gray color. It is very similar to hemoglobin in structure and sequence, but is not a tetramer; instead, it is a monomer that lacks cooperative binding. It is used to store oxygen rather than transport it.

Answer 3

By oxygen binding I suspect you mean either a transporter like hemoglobin or a reservoir like myoglobin..True, oxidases, peroxidases, etc., can transiently "bind " O2 to allow transfer of electrons ( e.g., cytochrome oxidase )but only Hb and Mb are transport/reservoir proteins for O2..  Myoglobin as explained earlier has one heme  and no cooperativity..( No Bohr Effect) and only releases its oxygen at lower O2 partial pressures ( < 7 mm ) so it is onvolved with supplying O2 under heavy exercise loads.