Ionic bonds-salt bridges
These are created when amino acids with opposing negative charges are next to each other in the hydrophobic core of a protein. This type of bond within the interior of a protein is rare as most of the charged amino acids are on the surface of a protein. Even though ionic bonds are rare they are important to protein structure as they are powerful electrostatic attractions that can achieve a strength close to that of a covalent bond. David Marcey. (2010). Bonding and Protein structure2
Water shells and charged surface residues
Amino acids that are electrically charged and mainly found on the surface of proteins promote the protein to fold appropriately by interacting with the water solvent. Polar water molecules can form shells around a residue side chains charged surface which helps to make the protein soluble and stabilise it. David Marcey. (2010). Bonding and Protein structure3
A hydrogen bond is formed when two atoms with partial negative charges share a partly positively charged hydrogen, these atoms are engaged in a hydrogen bond (H-bond). A proteins correct structure often depends on a complex network of this type of bond. These bonds can happen between a variety of atoms and involve:
• Atoms that are on two differing amino acid side chains
• Water molecules at the surface of a protein and atoms on an amino acid side chain.
• Protein backbone atoms and atoms on an amino acid side chain.
• Water atoms on a proteins surface and backbone atoms
• Two differing amino acids backbone atoms
Most H-bonds are found in a protein backbone between N-H and C=O groups and in either alpha helices or beta sheets. David Marcey. (2010). Bonding and Protein structure4
Hydrophobic bonds are a major force in correct protein folding....