haemoglobin and myoglobin

8 posts / 0 new
Last post
michaelsportscience's picture
haemoglobin and myoglobin

hello everyone,
It is my first time on this site after hearing such fantastic things about it and the people.
I am hoping there is someone who could explain, the difference between haemoglobin and moglobin, i understand that they our a protein, and that they bond to oxygen and this bond can be broken when needed by the muscle tissue. however i am desperate to find out why there is a diffence between, and what is it and how does it work.
anything will be greatly appreciated, thank you so much.
michael waterhouse

R Bishop
R Bishop's picture

Welcome to SSI.  Hope we can help.  I assume you are talking myoglobin vs hemoglobin? 
Here are the basics as far as I remember (with a little help from Google, wikipedia, and my BioChemistry book).
Hemoglobin functions in the transport of oxygen in the blood only. One hemoglobin can bind 4 O2 making it a pretty effective transport molecule. It does this by binding O2 to a 'heme' group which contains iron that likes to bind O2.
Myoglobin on the otherhand is actually found inside the tissues itself (think the red in red meat, that is oxygen bound myoglobin, you are seeing).  Myoglobin can only bind one O2, but it has a much greater affinity for that O2. It also binds O2 via a heme group, though beyond that the two proteins are unrelated at the amino acid level.
What is the function of myoglobin? Im pretty sure nobody knows oddly enough.  A transgenic mouse lacking the myoglobin gene was generated and it had no problems at all.  Bet they were shocked at that result.
If you have deeper or more specific questions, keep 'em coming.  Im sure some others will take a crack at answering your post soon as well.

shzad's picture

as grp admin mentioned both have O2 binding capacity
diffrences are
   hb has less binding affinity 4 O2 as cmpared to myoglobin
   myoglobin can be fully saturated means to 100% while Hb is saturated to max 80%
    structural diffrence is also there which causes 4 O2 molecules binding toHb and 1 O2 molecule with Mb
function can easily read frm book for HB 
whle myoglon act as storin for O2 in exercise and delivers O2 to the cell when its needed.
in this way it also unload the HB which is now free to more O2 entrapment
        need more help cn cntact me

varsha's picture
You may also like to look at

You may also like to look at more information on myoglobin and hemoglobin at protein databases. The following entries are for human genes from one of my favorite site, Expasy.
You can expolre protein sequence, motifs, polymorphisms, cellular localization  and links to original references among other things.
human myoglobin
human hemoglobin beta
If you have specific questions, go right on.
I am also moving this post to "Biochemistry" forum.

Arvind Singh Pundir
Arvind Singh Pundir's picture
Any discussion of protein

Any discussion of protein structure begins with myoglobin, because myoglobin is where the science of protein structure really began. After years of arduous work, John Kendrew and his coworkers determined the atomic structure of myoglobin, laying the foundation for an era of biological understanding, Our blood stream contains about 150 g/L of the protein known as hemoglobin (Hb), which is so effective as an oxygen-carrier that the concentration of O2 in the blood stream reaches 0.01 M   the same concentration as air. Once the Hb-O2 complex reaches the tissue that consumes oxygen, the O2 molecules are transferred to another protein  myoglobin (Mb)  which transports oxygen through the muscle tissue it is a small, bright red protein and is very common in muscle cells, and gives much of its red color. Its job is to store oxygen, for use when muscles are hard at work 
The Chemistry of Hemoglobin and Myoglobin : →  chemed.chem.purdue.edu/genchem/topicreview/bp/1biochem/blood3.html
 A nice PPT  briefing haemoglobin and Myoglobin : →  www.rpahsoc.org/HbMb03a_MGuss.ppt
 A resource for studying Biological macromolecules like hemoglobin , Myoglobin etc.→  www.rcsb.org/pdb/home/home.do

tazuk's picture
 why don't you use wikipedia

 why don't you use wikipedia and google to find answers of these simple questions

varsha's picture
Hello Tazuk.

Hello Tazuk.
I agree that you can find out most of the info yourself, it might take a while. I would not trust Wikipedia much except for quick info.
A discussion on SSI brings out diffrent views which is very  informative and often comes with references and links. Besides, many of the SSI members are students who may need understanding of basic things and we encourage such discussion.

tazuk's picture
 fair enough :)

 fair enough :)