relationship between proteins and polypeptides (1 Viewer)

[Rowena]

i dont get this dotpoint, arent polypeptides and proteins practically the same thing?

 

[babydoll_]

a gene codes for a polypeptide

and then many polypeptides make up proteins

therefore, one gene does not code for one protein

 

[Misturi]

I hate this dotpoint, l can't do anything with polypeptides - l don't get them at all.

Thanks babydoll for making it clearer

Oh babydoll - do we need to know any more of them or any more detail?

 

[withoutaface]

Proteins are a subset of polypeptides. While they are both chains of amino acids, they have to be in a certain order to be a protein (there are many different kinds of proteins, and as such a number of these sequences that exist), while a polypeptide can be any chain of amino acids.

EDIT: Read what babydoll_ said, she knows what she's talking about

 

[babydoll_]

that's about it for proteins and polypeptides i think; you don't need to know any more details unless youre doing 'genetics' for your option topic.

 

[Misturi]

I'm doing communication so thats fine.

So (without looking) genes code for polypeptides

Polypeptides make proteins

 

[Tommy_Lamp]

Yeah you need to know this for the Beadle and Tatum thing, how the hypothesis was changed from One Gene - One Protein to One Gene - One Polypeptide

 

[lukebennett]

dont forget the polypeptide synthesis bit though.

 

[neo o]

Polypetides are chains of amino acids joined by peptide bonds.

Proteins are polypeptides that have been folded into a specific shape

 

[lukebennett]

but arent proteins often severl polypeptides though? so does that mean that two genes may code for a protein?

 

[malkin86]

Yes, luke, that's why the onegene-oneprotein hypothesis was changed to one gene - one polypeptide. How was it proven to be wrong?

 

[lukebennett]

its just what neo said. proteins were polypeptides folded into a specific shape. or should he have said polypeptides folded into different shapes are proteins?

 

[Bjmoore93]

I really need help with this .. I am doing an assignment on explaining the relationship between polypeptide and proteins.... HELP please!!!!!!!!!!!!

 

[thongetsu]

lol thread revive!

 

[sinophile]

Let me get this clear.

A bunch of amino acids join together. This is called a polypeptide.

A few polypeptides join together. The thing is STILL called a POLYPEPTIDE. (Like lego: several lego bricks make a lego block. When you stick two lego blocks together, its still called a lego block.)

When you FOLD the polypeptide, it becomes a PROTEIN.

In other words, a protein refers to a certain way of folding a polypeptide.

 

[_blank]

From HSC Biology: HSC Online

A protein is made up of one or more polypeptides. A polypeptide is made up of a chain of many amino acids.

chain of AA --> polypeptide

1+ polypeptide --> protein

 

[Slidey]

Let me get this clear.

A bunch of amino acids join together. This is called a polypeptide.

A few polypeptides join together. The thing is STILL called a POLYPEPTIDE. (Like lego: several lego bricks make a lego block. When you stick two lego blocks together, its still called a lego block.)

When you FOLD the polypeptide, it becomes a PROTEIN.

In other words, a protein refers to a certain way of folding a polypeptide.

You're not far wrong. The definition of the terms is slightly organic, however (haha!)

Here's a good explanation:

The words protein, polypeptide, and peptide are a little ambiguous and can overlap in meaning. Protein is generally used to refer to the complete biological molecule in a stable conformation, whereas peptide is generally reserved for a short amino acid oligomers often lacking a stable three-dimensional structure. However, the boundary between the two is not well defined and usually lies near 20–30 residues.[10] Polypeptide can refer to any single linear chain of amino acids, usually regardless of length, but often implies an absence of a defined conformation.

Remember that both proteins and polypeptides are polymers of amino acids and you can't go wrong.