N-terminal peptides fragments

The N-terminal peptide fragment of des-angiotensinogen Val-Ile-His-Asn contains two strongly hydrophobic amino acid residues on the N-terminal site of His-3. The potentiometric data have shown that the NiH.2L complex with this albumin-like sequence is more than two orders of magnitude more stable than the respective complex with Gly-Gly-His.1744 The NMR-based molecular structure has shown that the side chains of Val-1 and lie-2 form a well-ordered hydrophobic fence (Figure 21) shielding one side of the coordination plane from the bulk of... 

The serum proteins C3 and C4, members of the complement system (Chapter 31), are converted into their active forms, C3b and C4b, by proteolytic removal of short N-terminal peptide fragments. 

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