You sequence a new protein that forms strong junctions between brain blood-vessel cells and discover that sulphur containing cysteine amino acids occur at regular intervals. What is the significance of this finding?Select one alternative:These cysteine amino acids will cause bends to occur in the tertiary structure of this junction protein.These cysteine amino acids will form disulphide bridges that will help stabilise the tertiary structure of this junction protein.These cysteine amino acids will form ionic bonds that will help stabilise the tertiary structure of this junction protein.The side chains of the cysteine amino acids will form the bonds that stabilise the α-helices and β-pleated sheets in this junction protein.
Question
You sequence a new protein that forms strong junctions between brain blood-vessel cells and discover that sulphur containing cysteine amino acids occur at regular intervals. What is the significance of this finding?Select one alternative:These cysteine amino acids will cause bends to occur in the tertiary structure of this junction protein.These cysteine amino acids will form disulphide bridges that will help stabilise the tertiary structure of this junction protein.These cysteine amino acids will form ionic bonds that will help stabilise the tertiary structure of this junction protein.The side chains of the cysteine amino acids will form the bonds that stabilise the α-helices and β-pleated sheets in this junction protein.
Solution
The correct answer is: These cysteine amino acids will form disulphide bridges that will help stabilise the tertiary structure of this junction protein.
Here's why:
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Proteins are made up of amino acids, and their structure is determined by the sequence of these amino acids.
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Cysteine is a unique amino acid because it contains a sulfur atom. This sulfur atom can form a covalent bond with another sulfur atom from another cysteine residue. This bond is called a disulfide bridge or disulfide bond.
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Disulfide bridges are important for the stability of a protein's structure, particularly its tertiary structure. The tertiary structure of a protein is its overall three-dimensional shape, which is crucial for its function.
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Therefore, the regular occurrence of cysteine amino acids in this new protein suggests that these cysteine residues are forming disulfide bridges, which are helping to stabilise the protein's tertiary structure. This could be particularly important for a protein that forms strong junctions between cells, as it would need to have a stable structure to function effectively.
Similar Questions
The amino acid cysteine has a sulfhydryl (-SH) group that can participate in the formation of a(n) bond, linking the sulfur atoms of two cysteine molecules.
Whilst sequencing this new brain blood-vessel junction protein you also discover that two variants exist, each with a different amino acid at position 79. Position 79 is in a region that spans the core of the plasma membrane. You conduct additional studies that demonstrate there is no difference in how these junction variant’s function. From these observations alone you can conclude that it is likely that the amino acids at position 79 in each variant have similar properties.only the primary structures of the two variants differ. the primary structure of the two variants differs, however the secondary, tertiary, and quaternary levels of structure may or may not differ.there is no difference between the primary, secondary, tertiary, or quaternary levels of structure between the variants.
What level of protein structure is stabilized by disulfide bonds between two adjacent cysteine residues?Group of answer choicesPrimarySecondaryTertiaryQuaternary
The amino acids in polypeptide chains which contain sulfur (S) areAnswers: A. Asparagine & glutamineB. Aspartic acid and Glutamic acidC. Proline and glycineD. Cysteine and methionineE. Tyrosine and tryptophan
The most common covalent cross-links in proteins are sulfur-sulfur bonds that form between two amino acids with -SH (thiol) groups as side chains. Which amino acid has this side chain?Question 14Select one:a.tryptophanb.methioninec.cysteined.proline
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