CH 13: Translation of mRNA

These flashcards cover key vocabulary and concepts related to the translation of mRNA and protein structure.

Methionine

An amino acid that is the only start codon, coded by AUG.

Wobble

A phenomenon where one tRNA can recognize more than one codon.

Polypeptide

A single chain of amino acids held together by peptide bonds.

Primary structure

The order of amino acids in a polypeptide chain determining its folding.

Secondary structure

Unique structures formed in proteins due to hydrogen bonding between amino acids.

Tertiary structure

The overall 3D structure of a protein determined by interactions between amino acids.

Quaternary structure

The arrangement and interaction of multiple polypeptide chains.

Dimer

A protein structure consisting of two polypeptide chains.

Cysteine

An amino acid with a side chain that can form disulfide bonds.

Hydrophobic

Refers to non-polar amino acids that are typically buried within the protein structure.

Polar amino acids

Amino acids that are hydrophilic and likely to be on the surface of proteins.

Histidine

An amino acid that can be phosphorylated and is often targeted by prokaryotic kinases.

Amino acids

Building blocks of proteins, each having a unique side chain (R group).

Stop codon

Codons that terminate translation, including UAG, UAA, and UGA.

Anticodon

A sequence of three nucleotides in tRNA that is complementary to the codon in mRNA.

Protein kinase

An enzyme that adds a phosphate group to specific amino acids in proteins.

Peptide bond

The covalent bond formed between amino acids in a protein.

C terminus

The end of a polypeptide chain that has a free carboxyl group.

Wobble

A phenomenon where one tRNA can recognize more than one codon.

Polypeptide

A single chain of amino acids held together by peptide bonds.

Primary structure

The order of amino acids in a polypeptide chain determining its folding.

Secondary structure

Unique structures formed in proteins due to hydrogen bonding between amino acids.

Tertiary structure

The overall 3D structure of a protein determined by interactions between amino acids.

Quaternary structure

The arrangement and interaction of multiple polypeptide chains.

Dimer

A protein structure consisting of two polypeptide chains.

Cysteine

An amino acid with a side chain that can form disulfide bonds.

Hydrophobic

Refers to non-polar amino acids that are typically buried within the protein structure.

Polar amino acids

Amino acids that are hydrophilic and likely to be on the surface of proteins.

Histidine

An amino acid that can be phosphorylated and is often targeted by prokaryotic kinases.

Amino acids

Building blocks of proteins, each having a unique side chain (R group).

Stop codon

Codons that terminate translation, including UAG, UAA, and UGA.

Anticodon

A sequence of three nucleotides in tRNA that is complementary to the codon in mRNA.

Protein kinase

An enzyme that adds a phosphate group to specific amino acids in proteins.

Peptide bond

The covalent bond formed between amino acids in a protein.

C terminus

The end of a polypeptide chain that has a free carboxyl group.

N-terminus

The end of a polypeptide chain that has a free amino group.

Alpha-helix

A common protein secondary structure characterized by a tightly coiled spiral shape stabilized by hydrogen bonds.

Beta-sheet

A common protein secondary structure formed by extended polypeptide strands arranged side-by-side, stabilized by hydrogen bonds, creating a pleated appearance.

Disulfide bond

A strong covalent bond formed between two cysteine residues, critical for stabilizing tertiary and quaternary protein structures.

Molecular chaperone

Proteins that assist in the proper folding of newly synthesized or denatured proteins, preventing aggregation.

Post-translational modification

Covalent modifications to proteins after their synthesis, such as phosphorylation or glycosylation, which can alter function or stability.

Hydrophilic

Refers to polar or charged amino

Wobble

A phenomenon where one tRNA can recognize more than one codon.

Polypeptide

A single chain of amino acids held together by peptide bonds.

Primary structure

The order of amino acids in a polypeptide chain determining its folding.

Secondary structure

Unique structures formed in proteins due to hydrogen bonding between amino acids.

Tertiary structure

The overall 3D structure of a protein determined by interactions between amino acids.

Quaternary structure

The arrangement and interaction of multiple polypeptide chains.

Dimer

A protein structure consisting of two polypeptide chains.

Cysteine

An amino acid with a side chain that can form disulfide bonds.

Hydrophobic

Refers to non-polar amino acids that are typically buried within the protein structure.

Polar amino acids

Amino acids that are hydrophilic and likely to be on the surface of proteins.

Histidine

An amino acid that can be phosphorylated and is often targeted by prokaryotic kinases.

Amino acids

Building blocks of proteins, each having a unique side chain (R group).

Stop codon

Codons that terminate translation, including UAG, UAA, and UGA.

Anticodon

A sequence of three nucleotides in tRNA that is complementary to the codon in mRNA.

Protein kinase

An enzyme that adds a phosphate group to specific amino acids in proteins.

Peptide bond

The covalent bond formed between amino acids in a protein.

C terminus

The end of a polypeptide chain that has a free carboxyl group.

N-terminus

The end of a polypeptide chain that has a free amino group.

Alpha-helix

A common protein secondary structure characterized by a tightly coiled spiral shape stabilized by hydrogen bonds.

Beta-sheet

A common protein secondary structure formed by extended polypeptide strands arranged side-by-side, stabilized by hydrogen bonds, creating a pleated appearance.

Disulfide bond

A strong covalent bond formed between two cysteine residues, critical for stabilizing tertiary and quaternary protein structures.

Molecular chaperone

Proteins that assist in the proper folding of newly synthesized or denatured proteins, preventing aggregation.

Post-translational modification

Covalent modifications to proteins after their synthesis, such as phosphorylation or glycosylation, which can alter function or stability.

Hydrophilic

Refers to polar or charged amino acids that readily interact with water and are often found on the surface of proteins.

What are the four main components attached to the central alpha-carbon of every amino acid?

1. An amino group ( -NH_2 ), 2. A carboxyl group ( -COOH ), 3. A hydrogen atom, 4. A unique side chain (R group).

By what type of chemical reaction are peptide bonds formed between amino acids?

A dehydration reaction (also known as a condensation reaction), where a water molecule is removed.

What characteristic of the peptide bond rigidifies the polypeptide backbone?

Its partial double-bond character, which limits rotation around the C-N bond.

Where do the hydrogen bonds form that stabilize alpha-helices and beta-sheets in proteins?

Between the carbonyl oxygen ( C=O ) of one peptide bond and the amino hydrogen ( N-H ) of another peptide bond in the polypeptide backbone.

Name the primary types of interactions that determine and stabilize a protein's tertiary structure.

1. Hydrophobic interactions, 2. Ionic bonds (salt bridges), 3. Hydrogen bonds, 4. Disulfide bonds, 5. Van der Waals interactions.