Could an organism have several oxygen transport proteins?
Can an organism have several types of oxygen carriers in its blood?
Note that I am not asking how the creature could have evolved, that is too much sci-fy, genetically engineering or Deus Ex Machina evolution fits fine.
The idea to use several kinds of oxygen carriers is to be able to survive in very different environments (the last substance isn't very important if it causes problems):
- Hemoglobin: Standard carrier. Contains iron. Most efficient for normal purposes.
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Hemerythrin: Contains iron. Can also be made with cadmium.
Usually lacks cooperative binding, which means that it can only carry 1/4 of the O2 carried by haemoglobin (in some brachiopods it does).
Hemerythrin affinity for CO is lower than its affinity for O2, unlike hemoglobin which has a very high affinity for CO, i.e: resistant to CO poisoning.
Recent evidence has revealed hemerythrin to be a multi-functional protein "“ contributing to innate immunity and anterior tissue regeneration in worms. -
Hemocyanin. Contains copper, which means it doesn't need iron.
Lacks of cooperative binding, which means that it only carries 1/4 of the O2 carried by haemoglobin (in some hemocyanins of horseshoe crabs and some other species of arthropods, cooperative binding is observed,). However, it doesn't lose efficiency in cold environments with low oxygen pressure as hemoglobin does. In addition, it can stand elevated temperatures as high as 90 degrees Celsius.
Hemocyanin oxygen-binding profile is also affected by dissolved salt ion levels and pH.
It's believed to reduce cancer effects. - Vanabins: Contain vanadium or other rare minerals. Are very bad for transporting oxygen but are poisonous for many predators, parasites and microorganisms.
The question is if it could be possible to an organism to have all these substances or would them produce problems between them? If that is true, could the same organism has all these substances but not at the same time (i.e: it changes of substance according to the environment)?
This post was sourced from https://worldbuilding.stackexchange.com/q/138695. It is licensed under CC BY-SA 4.0.
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