L (leucine), an amino acid residue, is consist of mainly H (hydrogen) atoms and 1 N (nitrogen) atom.

H is an important component for L as H has no doubt made up the bulk of L. H is also involved in linking of L with other amino acid residues, through the formation of H bonds within the amino acid residues. Thus, it maintains a stable secondary and tertiary structure for the protein. However, H is always the side chain atoms for L and often a leaving atom that leaves L easily.

N, on the other hand, exists as an unique single atom in L. It is never a leaving atom for L, as L can never be an amino acid without the presence of N. However, N is positively charged and binds with other atom when there's a change in the condition of the environment.

So which is more important to L? H or N?

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