What level of protein structure is determined by the following:
b. Hydrogen bonds between backbone carbonyl oxygen atoms and hydrogen atoms attached to backbone nitrogen atoms?

Verified step by step guidance

1. Understand the levels of protein structure: Proteins have four levels of structure—primary, secondary, tertiary, and quaternary. Each level describes a different aspect of the protein's organization.
2. Recall the definition of secondary structure: The secondary structure of a protein is determined by hydrogen bonding between the backbone carbonyl oxygen atoms (C=O) and the hydrogen atoms attached to the backbone nitrogen atoms (N-H). These interactions form specific patterns such as alpha-helices and beta-pleated sheets.
3. Identify the type of bonding described in the problem: The problem specifies hydrogen bonds between the backbone carbonyl oxygen and backbone nitrogen hydrogen atoms, which is characteristic of secondary structure.
4. Relate the bonding to the structural patterns: These hydrogen bonds stabilize the alpha-helices and beta-sheets, which are the two main types of secondary structure in proteins.
5. Conclude that the level of protein structure described in the problem is the secondary structure, as it is defined by these specific hydrogen bonding interactions.

Key Concepts

Protein Structure Levels

Proteins have four levels of structure: primary, secondary, tertiary, and quaternary. Each level represents a different aspect of protein organization, from the sequence of amino acids (primary) to the overall three-dimensional shape (tertiary) and the assembly of multiple polypeptide chains (quaternary). Understanding these levels is crucial for grasping how proteins function.

Secondary Structure

Secondary structure refers to the local folding of the polypeptide chain into specific shapes, primarily alpha helices and beta sheets. These structures are stabilized by hydrogen bonds between the backbone atoms, specifically between carbonyl oxygen atoms and hydrogen atoms attached to nitrogen atoms in the peptide bonds. This level of structure is essential for the overall stability and function of proteins.

Hydrogen Bonds in Proteins

Hydrogen bonds are weak interactions that occur between a hydrogen atom covalently bonded to an electronegative atom and another electronegative atom. In proteins, these bonds play a critical role in stabilizing secondary structures by forming between the backbone atoms, influencing the protein's shape and functionality. Understanding these interactions is key to studying protein dynamics.