ABSTRACT
Cellular proteins from different domains of life are operating in their respective ecosystems. Weak forces form the tertiary structure. Is there a modulation of these interactions for different domains of life? Using a large database of X-ray structures of protein, we demonstrate that unlike eukarya and bacteria, archaeal proteins show an increase in salt-bridge, a decrease in π-π (hydrophobic) and the maintained level of cation-π (also anion-π) types of interactions. These observations clearly suggest environment specific modulation of weak forces. It, thus, seems that the intrinsic composition of amino acid in archaeal proteins and the extreme environment together maintain the stability of these proteins.
