Tertiary and Quaternary structure

• The tertiary structure is the third level of organization, with alpha helices and beta pleated sheets as the secondary structures.
• Alpha helices and beta sheets integrate with each other to form a protein with a unique 3D structure.
• The tertiary structure is held in place by bonds between the r groups of the amino acids.
• The secondary structure is held by hydrogen bonds between cos and nh groups of every amino acid.
• The overall folding up between alpha helices and beta sheets etc will be held up by bonds between r groups.
• Hydrogen bonds can form between any delta and minus and delta plus, as long as the r groups are polar.
• Ionic bonds involve ionic charges and form between any positive and negatively charged r groups.
• Disulfide links or bridges form between any r groups that have sulfur atoms in them.
• The specific 3D structure of a protein is also determined by hydrophilic and hydrophobic r groups.
• The amino acids with the hydrophobic r groups tend to be found in the center of the protein.
• The overall 3D structure of a protein is determined by the properties and interactions of the amino acids' r groups.
• The primary structure determines the tertiary structure of a protein.
• The tertiary structure is the specific interaction and folding of all 3D shapes into a unique shape, driven by bonds of the amino acids' r groups.
• The quaternary structure of a protein is the structure formed by multiple polypeptide chains interacting together.
• Proteins in cells are often composed of multiple polypeptide chains interacting together.
• Hydrophobic amino acids point into the interior of a protein, while hydrophilic amino acids face outwards, attracting water.
• Some proteins are composed of one polypeptide chain, while others are composed of multiple polypeptide chains interacting together.
• The tertiary structure of a protein is the overall specific 3D shape of a protein, determined by interactions between r groups and the properties of those r groups.
• Proteins can have non-protein groups, known as prosthetic groups, added in, forming conjugated proteins.
• Hemoglobin is composed of four polypeptides interacting together.
• The overall mix of the prosthetic groups and the polypeptides makes a conjugated protein.
• Some proteins stop at the third level but some carry on to the fourth level if they have another chain or more than one chains or they have prosthetic groups or both.
• Protein structure is crucial as it determines the unique shapes and functions of proteins.
• The bonding of the different chains and these prosthetic groups results in the formation of proteins with very complex and unique quaternary structures.
• The bonds that maintain the structure of proteins can be broken if the temperature or the pH is altered, causing the protein to become denatured and lose its shape, preventing it from carrying out its function.
• The quaternary structure of a protein is the specific 3D shape of a protein determined by the multiple polypeptide chains and or prosthetic groups bonded together.
• The primary structure, which is the order of amino acids, determines the secondary and the tertiary and the quaternary structures of a protein.
• Hemoglobin interacts with two blue polypeptides and cannot function without these prosthetic groups associated with the protein.
• The secondary structure of a protein is determined by the hydrogen bonds that form structures like the alpha helix and the beta sheets.
• The quaternary structure of a protein is determined by the bonding of the different chains and these prosthetic groups.
• The tertiary structure of a protein is determined by the positions and parts along the polypeptide chain.