Talk:Hemoglobin

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is it better to have structure and synthesis together? The edit about chemical formula of Hb is not accurate. Does it refer to HbA, HbA2, HbF which have varying numbers of amino acids? " Hemoglobin is chemically represented by (C₂₉₅₂H₄₆₆₄N₈₁₂O₈₃₂S₈Fe₄). "

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Paragraph four wants attention: it's a pointless distinction between "broken down" and "broken up." But the paragraph makes it sound as if the hemoglobin and a red blood cell are always recycled at the same time. So it would seem that each red blood cell has a certain amount of hemoglobin that stays with it for the duration of that cell's life? Is that the case? (interesting, but not as cute as monogamous ducks.) :-D

Point taken. I hope it's a bit clearer now. On your other point, human red blood cells I believe are pretty much stuck with their initial load of hemoglobin. Mammalian red blood cells don't have cell nuclei, so they can't be doing much de novo synthesis of any protein. Reptile blood cells do have nuclei (or Jurassic Park would have lost its major plot premise), so they might do synthesis. I'm not a herpetologist so I don't know.

Just a side note: The classification of Dinosaurs is a hotly debated topic. They are not what we would call reptiles because of their activity levels and other physio/morpho-logical differences that can be inferred/ascertained from the fossil record. In fact they are closer to birds in many respects. So we can not say whether or not the RBCs of of dinos had nuclei or not. However, all blood from almost every animal has white blood cells in it, that almost without expection all have nuclei with at least some DNA. maveric149

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The paragraph recently moved to the bottom probably should be used as the introduction to a new topic called oxygen transport. - Dwmyers

I just added the part about carbon dioxide. I know that it is not constructed very well but I thought it was an important point. Do you think the bohr effect deserves a page of it own? or should it just be defined in this article? DiJay

Question: Since heme is formed in the mitochondria, and mammalian erythrocytes do not have mitochondria in order to provide more space for hemoglobin, how exactly is hemoglobin made for the red blood cell? Especially without a nucleus to create any mRNA.

Immature mammalian erythrocytes have both nuclei and mitochondria: the hemoglobin carried in the mature cell is made in the immature cell, before it loses them. - Nunh-huh 04:07, 22 Oct 2004 (UTC)

Contents 1 4 chains vs. 2 chains 2 Human Hemoglobin Levels 3 Salt bridges 4 hemoglobin and aging 5 Consistency 6 Feature article anyone? 7 Question 8 What?

[edit] 4 chains vs. 2 chains

I read some time ago that while in "higher" animals including humans, 2 strands of alpha-hemoglobin combine with 2 strands of beta-hemoglobin, in "lesser" animals, the hemoglobin consists only of 2 alpha-strands (enclosing, as usual, an iron atom). Unfortunately, I had no luck finding more info on the Internet - could somebody who knows about this please elaborate? Aragorn2 11:50, 23 Oct 2004 (UTC)

If you go "low" enough, hemoglobin acts on nitrous oxide rather than oxygen [1]. A little "higher" and animals have large molecular weight hemoglobins that are carried in the plasma. Move on up to birds and mammals, and there's small molecular weight hemoglobins that are packaged in red blood cells [2]. The respiratory protein of "lower" animals certainly isn't always simpler (snail hemocyanin, for example, has 10 subunits). I don't know of any animals that have only two alpha-strands as a functional hemoglobin, and alpha-beta dimers are ineffective oxygen carriers, so something's been lost since your read it, or the missing info is in a veterinary source somewhere. - Nunh-huh 14:08, 23 Oct 2004 (UTC)

Thanks for the links. I had read about the worm before, but from this text, it's not obvious whether the worm has dimer or tetramer (or even monomer?) hemoglobin. After another Google search, I found this:

http://www.aw-bc.com/mathews/ch07/c07emhp.htm

and a possible scenario for hemoglobin evolution on this page:

http://www.asa3.org/evolution/irred_compl.html

So the lamprey has alpha-alpha-dimer hemoglobin which splits apart when oxygenated, which is what I was referring to.

Got it now.. looks like:

• hagfish: monomeric hemoglobin in most species, some have hgb that is dimeric when deoxygenated and monomeric when oxygenated
• lamprey: monomeric when oxygenated, dimeric or tetrameric when deoxygenated
• sharks: dimeric when oxygenated (α₁β₁); tetrameric when deoxygenated
• vertebrates: α₂β₂ dimers

That was a very interesting question! we ought to put a chart or a synopsis in the article. - Nunh-huh 03:52, 24 Oct 2004 (UTC)

There are variety of hemoglobin predecessors, many of which have different names. Such as Erythrocruorin in worms and myoglobin which is a monomer and has no arrogating ability. Erythrocruorin should get an article for it self, I can easily scrounge up enough information and generate image of the protein from pubmed, but I lack the time.--BerserkerBen 22:58, 31 Jan 2005 (UTC)

[edit] Human Hemoglobin Levels

I don't know much about the chemistry of hemoglobin and the like, but a section detailing how and why hemoglobin levels are measured in humans. A table or something illustrating the distribution and ideal hemoglobin level would also be great. My doctor just called me and all he said was "14,7" and I have absolutly no clue what that means. Google will answer me in minutes, but still, I was hoping Wikipedia would have it. --Crucible Guardian 6 July 2005 01:29 (UTC)

[edit] Salt bridges

What does salt bridges mean in this context? Not the same as the linked article, anyhow. / Habj 18:28, 20 October 2005 (UTC)

I suspect it means ionic bonds but since I don't know, I just remove it and rephrase the sentence. / Habj 19:07, 21 October 2005 (UTC)

That's correct. See here / Djdaedalus 14:50, 24 October 2005 (UTC)

[edit] hemoglobin and aging

Sometime in the past I read that in humans, oxygen transport decreases by 1% per year after the age of 20, which I can believe, being now 65. Is there information on the aging process and oxygen transport that could be summarized in a short paragraph?

If someone supplies the references, yes (see WP:CITE). A quick Google will probably yield some results. JFW | T@lk 08:51, 2 December 2005 (UTC)

[edit] Consistency

This article goes back and forth between hemoglobin and haemoglobin. Pick one and stick with it, but mention both in the first sentence. I believe the hemoglobin spelling is more universal throughout medical literature, but I don't know about common usage outside the US. Hichris 17:39, 16 December 2005 (UTC)

It was pretty uniform at "hemoglobin" until this was changed [3]. My literature might have been american, but I think hemoglobin is the one to choose. / Habj 03:46, 17 December 2005 (UTC)

I would prefer hæmoglobin! That is the traditional spelling. Failing that, then haemoglobin. It's only in North America that the "simplified" version is used. EuroSong ^talk 09:30, 2 November 2006 (UTC)

[edit] Feature article anyone?

Anyone think this artilce shoukld be nominated as a feature article? If not why?--BerserkerBen 07:31, 31 December 2005 (UTC)

It is not ready. Saravask 20:01, 31 December 2005 (UTC)

What needs to be done to make it ready? --BerserkerBen 20:06, 17 January 2006 (UTC)

I can think of some points. Firstly, the spelling is inconsistent (BE/AE). There is no history section; we don't learn who discovered it, when it was first sentenced, linked and cloned, why Linus Pauling won the Nobel Prize in relation to it, why the Bohr effect is called like that, etc etc. In short, more context. Classic references are very useful. JFW | T@lk 21:28, 17 January 2006 (UTC)

Great can we list those things up on top of the discussion board as things needed for improvemnt?--BerserkerBen 23:59, 17 January 2006 (UTC)

[edit] Question

So pretty much hemoglobin is a key to a healthy heartbeat.

Uhh, that is only partially true. For a healthy heartbeat the hemoglobin-containing blood also needs to be delivered to the myocardium, which requires a functioning coronary circulation unimpaired by atherosclerosis, as well as a myocardium that is not remodelled as a result of excessive strain, poor metabolism or hereditary muscle abnormalities. There is really quite a lot to a healthy heartbeat... JFW | T@lk 17:17, 8 February 2006 (UTC)

[edit] What?

This process also produces one molecule of carbon monoxide for every molecule of heme degraded [4]; this is one of the few natural sources of carbon monoxide production in the human body, and is responsible for the normal blood levels of carbon monoxide even in people breathing pure air.

Am I the only one that finds this a bit wierd, saying, "Pure" air. What exactly is "unpure" air. I think this should be reworded but I'm not sure how. --RobertDahlstrom 18:32, 9 November 2006 (UTC)

That's a good question. I can only guess that "pure air" refers to the "normal" atmospheric mix of gasses, of which carbon monoxide composes only trace amounts. – ClockworkSoul 19:04, 9 November 2006 (UTC)