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    what is the importance of hydrogen bonding and disulfide bridges in maintaining the 3d structure of protein?
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    (Original post by Reann01)
    what is the importance of hydrogen bonding and disulfide bridges in maintaining the 3d structure of protein?
    Well, if you think of a protein at the very basic level, it is essentially a string of amino acids and each protein has a unique order of amino acids. The string (aka the primary structure) then forms the tertiary structure by forming various bonds between other amino acids in this string. Because of the unique order of amino acids in the primary structure, the tertiary structure is also highly unique because there are tonnes of combinations of bonds that can form between different amino acids in different locations in the primary structure. These bonds are also strong, but they can be broken by high temperatures, which is known as denaturing.

    I hope that helps
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    (Original post by Reann01)
    what is the importance of hydrogen bonding and disulfide bridges in maintaining the 3d structure of protein?
    First, let's go over the different levels of protein structure. The primary structure of a protein is simply the sequence of amino acids in the polypeptide chain. The secondary structure is the folding of a polypeptide chain in local segments to produce 3D shapes such as alpha helices and beta-pleated sheets due to hydrogen bonding between amino and carboxyl groups on amino acid residues. The tertiary structure of a protein is the overall 3D geometric shape of the polypeptide chain due to interactions between R groups. Quaternary structure is the overall 3D geometric shape involving proteins with multiple polypeptide chains - the best example of this is haemoglobin.

    There are four main types of interactions between R groups which maintain the tertiary structure: hydrogen bonds (between partially charged/polar hydrogen and oxygen atoms), ionic bonds/salt bridges (between oppositely charged R groups), Van der Waals' forces (between non-polar R groups) and disulphide bonds (covalent bonds between two cysteine residues. There are also interactions between hydrophilic/polar R groups and water - this allows globular proteins such as enzymes to be soluble.

    With the exception of disulphide bridges (covalent bonds), these forces are quite weak individually, however, collectively the forces can add up which helps stabilise the tertiary structure. Disulphide bridges do not form in the cytoplasm of cells as it is a reducing environment; therefore, disulphide bridges are only important in stabilising proteins that are secreted into the extracellular environment.
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    (Original post by Jpw1097)
    First, let's go over the different levels of protein structure. The primary structure of a protein is simply the sequence of amino acids in the polypeptide chain. The secondary structure is the folding of a polypeptide chain in local segments to produce 3D shapes such as alpha helices and beta-pleated sheets due to hydrogen bonding between amino and carboxyl groups on amino acid residues. The tertiary structure of a protein is the overall 3D geometric shape of the polypeptide chain due to interactions between R groups. Quaternary structure is the overall 3D geometric shape involving proteins with multiple polypeptide chains - the best example of this is haemoglobin.

    There are four main types of interactions between R groups which maintain the tertiary structure: hydrogen bonds (between partially charged/polar hydrogen and oxygen atoms), ionic bonds/salt bridges (between oppositely charged R groups), Van der Waals' forces (between non-polar R groups) and disulphide bonds (covalent bonds between two cysteine residues. There are also interactions between hydrophilic/polar R groups and water - this allows globular proteins such as enzymes to be soluble.

    With the exception of disulphide bridges (covalent bonds), these forces are quite weak individually, however, collectively the forces can add up which helps stabilise the tertiary structure. Disulphide bridges do not form in the cytoplasm of cells as it is a reducing environment; therefore, disulphide bridges are only important in stabilising proteins that are secreted into the extracellular environment.
    Thank you this helped alot !
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    (Original post by AortaStudyMore)
    Well, if you think of a protein at the very basic level, it is essentially a string of amino acids and each protein has a unique order of amino acids. The string (aka the primary structure) then forms the tertiary structure by forming various bonds between other amino acids in this string. Because of the unique order of amino acids in the primary structure, the tertiary structure is also highly unique because there are tonnes of combinations of bonds that can form between different amino acids in different locations in the primary structure. These bonds are also strong, but they can be broken by high temperatures, which is known as denaturing.

    I hope that helps
    Thanks it did ☺
 
 
 
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