Protein Conformation

[mjl1717]

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Can anyone give the definiitons and give examples of secondary, tertiary, quarternary structures of proteins??

 

[lasek]

Can anyone give the definiitons and give examples of secondary, tertiary, quarternary structures of proteins??

Secondary structure is the alpha helix and beta sheath (or beta pleats). If I remember correctly they are formed by hydrogen bonding within an amino acid. Alpha helix looks like a spring. beta sheath is just folds (think of a strip of paper slightly bent). I cant really describe what they look like any better than that, just google for an image of it. Once you'll see it, you'll know what I mean
Tertiary structure is how the whole protein folds to have function. The exact process of how proteins fold is unknown. It is held together with hydrogen bonding between the different amino acids, disulfide bridges, and hydrophobic-hydrophilic interactions. There are similar folds in proteins that have similar function. So for example most rtansmebrane receptors have 7 transmebrane domains with a similar structure, but differ in the ligand binding domain.
Quarternary structure is when several protein chains are attached to each other. Think of normal hemoglobin which has two alpha and two beta units, (dont confuse with alpha an beta folds) which form the actual hemoglobin molecule.

Hope this helps somewhat. If you need more detailed explanation, you can ask me further.

 

[Ramoray]

for f sakes, ill be damned if im goign to memorize 1, 2 and tertiary structures of protiens again.. what is this HS bio, college bio, biochem, mcat.. **** i have memorized that so many times, sure i konw the basics but i never rmemeber which bonds exactly are in which one and when you denature a protien does it leave its 2, or 3 or what.. **** that hsit

 

[Pox in a box]

for f sakes, ill be damned if im goign to memorize 1, 2 and tertiary structures of protiens again.. what is this HS bio, college bio, biochem, mcat.. **** i have memorized that so many times, sure i konw the basics but i never rmemeber which bonds exactly are in which one and when you denature a protien does it leave its 2, or 3 or what.. **** that hsit

Ramoray, do you curse like that in front of patients and your classmates?

 

[mjl1717]

Thx for the quick response, this type of q was on my exam.
Does anyone have ANY other examples??

 

[Ramoray]

Ramoray, do you curse like that in front of patients and your classmates?

classmates-yes
patients- nooo oh oh no

 

[Pox in a box]

classmates-yes
patients- nooo oh oh no

What's the difference? I don't want to preach but don't assume that just because many of your peers might say, do, or approve of all the things you say or do. The same goes with your patients. Same goes with SDN. 😍

 

[Wrigleyville]

I can't believe they asked a question like that... Ramoray is right-- that is a 10th grade biology question.

 

[Ramoray]

revised
patients- no oh hhh nooo
sdn- nooooo hohoh nooo
friends- um still yes
classmates-most are tools so -- yessss eeee dee dee
pox-.. Noooooo never!

peace!

 

[hdu]

Secondary structure:
It’s the conformation present in a local region of the polypeptide, stabilized through hydrogen bonds between the elements of the peptide bond.
(Interactions of neighboring amino acids)
Types:
• Random disposition
• a-helix
Right handed
Left handed
• b-pleated sheet
Parallel
Antiparallel
• b-turn

Tertiary structure:
• It’s the spatial conformation of protein stabilized through several interactions between the R side chain of distant amino acids residues.
Maintained by:
• Hydrogen bonds between the R side chain of distant amino acids
• Ionic interactions
• Ester linkages
• Disulfide bridges
• Hydrophobic interactions

Quaternary Structure:
It’s the assembly of several polypeptide to make an unique functional protein stabilized through several noncovalent interactions between the R side chain of amino acids from different peptide chains. It describes the three dimensional relation among the different polypeptide chains

 

[mjl1717]

Secondary structure:
It’s the conformation present in a local region of the polypeptide, stabilized through hydrogen bonds between the elements of the peptide bond.
(Interactions of neighboring amino acids)
Types:
• Random disposition
• a-helix
Right handed
Left handed
• b-pleated sheet
Parallel
Antiparallel
• b-turn

Tertiary structure:
• It’s the spatial conformation of protein stabilized through several interactions between the R side chain of distant amino acids residues.
Maintained by:
• Hydrogen bonds between the R side chain of distant amino acids
• Ionic interactions
• Ester linkages
• Disulfide bridges
• Hydrophobic interactions

Quaternary Structure:
It’s the assembly of several polypeptide to make an unique functional protein stabilized through several noncovalent interactions between the R side chain of amino acids from different peptide chains. It describes the three dimensional relation among the different polypeptide chains

Thx guys esp hdu and lasek(everyone else was crying)
For quarternary structure:
Protein can exist as subunits which bind with other subunits ( that can also exist as independent globular proetins.) The cell can control the binding of these subunits which can eventually form a multiunit protein. Example of this would be flagella and spindle formation. [Hemoglobin is the only example I know of with 4 subunits]
Primary structure is basically sequencing in relation to what kind of side group the amino acidic has aliphatic, imino, acidic ,hydroxyl, aromatic, imadazole group, hydrogen group, or friendly sulphur groups etc.
So the most difficult would be the difference between secondary and tertiary
protein structure