Tertiary structure: The overall shape of a protein molecule; and the spatial relationship of the secondary structures to one another; is called the tertiary structure of the protein. In other words, the various folds which give three-dimensional appearances to protein form its tertiary structure. This structure is stabilised by the various bonds like hydrogen bond, disulphide bond, electrostatic bond, hydrophobic bonds, Van der Waals forces and peptide bond.
An ester bond is formed between sugar and phosphate in a nucleotide. DNA and RNA are composed of nucleotides that are linked to one another in a chain by chemical bonds, called ester bonds, between the sugar base of one nucleotide and the phosphate group of the adjacent nucleotide. This bond is least likely to be involved in stabilizing of the protein.