proteins & polypeptides (1 Viewer)

[MiSSi]

hey i cant find this anywhere!
explain the relationship between proteins and polypeptides. thanks

 

[xiao1985]

polypeptide is just more than 1 amino acid joint together...... while protein is a definite sequence of specific amino acids joint together....... hence, a protein is a polypeptide but a polypeptide is not necessary a protein.......

an analogy would be: an amino acid is a letter, a polypeptide can be just some random letters while a protein is sort of like a word......

uhm, dont use that analogy in exam, cuz... i dunt fink the hsc mark would accept it.....

 

[jims]

maybe thats right n im wrong but isnt a polypetide chain a sequence of amino acids? so the gene codes for a polypeptide, which may be a protein. however, some proteins are made up of several polypeptide chains. i can think of haemoglobin which has 4 polypetide chains. so basically, proteins are made up of polypetide chains which are made up of amino acids.

 

[ballerinabarbie]

Originally posted by jims
maybe thats right n im wrong but isnt a polypetide chain a sequence of amino acids? so the gene codes for a polypeptide, which may be a protein. however, some proteins are made up of several polypeptide chains. i can think of haemoglobin which has 4 polypetide chains. so basically, proteins are made up of polypetide chains which are made up of amino acids.

you are right...

 

[iambored]

from a chem perspective..
i understand it by that amino acids join, to make polypeptides. when you have over i think it was 200/400 it can be classed as a protein. although, jims, i didn't know the bit about several chains, thanks for that

 

[arls]

amino acids are linked by peptide bonds to make polypeptides. Several polypeptides linked together = protein.