H-d-Phe-d-Pro-Gly methyl ester hydro-chloride monohydrate

Area of Science:

• Biochemistry
• Structural Biology
• Crystallography

Background:

• Peptide conformation dictates biological function.
• Understanding peptide secondary structures is key to drug design.
• Previous studies on related analogues provide context.

Purpose of the Study:

• To determine the molecular conformation of the title tripeptide methyl ester hydrochloride monohydrate.
• To investigate the stabilizing interactions within the crystal structure.
• To compare the conformation with related analogues and understand structure-inducing factors.

Main Methods:

• X-ray crystallography was used to determine the three-dimensional structure.
• Analysis of intermolecular interactions, including hydrogen bonds and solvent interactions.
• Comparison of the determined structure with previously reported structures of similar compounds.

Main Results:

• The title tripeptide methyl ester hydrochloride monohydrate adopts an extended conformation.
• The structure does not conform to typical secondary structure classifications.
• Stabilizing interactions involve water molecules, chloride ions, and peptide-peptide hydrogen bonds.
• A comparison with a Phe-d-Pro-Gly analogue suggests chirality influences beta-turn formation.

Conclusions:

• The specific arrangement of amino acid residues, particularly chirality, is critical for inducing specific peptide conformations like beta-turns.
• The observed extended structure is stabilized by a network of intermolecular interactions.
• Further research into structure-activity relationships of peptides is warranted.