Protein structure perfect paragraph

Protein structure and folding plays a large role in protein function. There are four levels of protein structure: primary, secondary, tertiary, and quarternary. All proteins have primary structure, which is the sequence of amino acids. The amino acids of a protein are kept together with covalent, peptide bonds. After primary structure comes the secondary structure, which are structures amino acid sequences organize into. Secondary structure involves alpha helices and beta sheets. The alpha helix is similar to the structure of DNA while beta sheets that look like flat sheets. The bonds that are prominent in secondary structure are hydrogen bonds between the backbone atoms of the protein. The overall folding of a single polypeptide chain is call its tertiary structure. If there are more than one polypeptide chains coming together to function, it is referred to as quarternary structure. Not all proteins have quarternary structure, but all proteins have up to tertiary structure. Hydrogen bondng, Van der waals interactions, disulfide bonding, and ionic bonding occurs tertiarty and quarternary bonding. Understanding the levels of protein folding allows us to understand how these proteins function and interact with one another.