Discovery and Characterisation of Novel Poly-Histidine-Poly-Glycine Peptides as Matrix Metalloproteinase Inhibitors.

For the first time, two poly-histidine-poly-glycine peptides (pHpG-H5 and pHpG-H7) were identified as promising candidates for matrix metalloproteinase inhibitors. cDNAs encoding pHpG-H5 and pHpG-H7 peptides were isolated from the Atheris squamigera cDNA library constructed using oligo(dT)-primed reverse transcription. Deduced sequences of pHpG peptides were systematically organised and utilised as templates for synthesising chemical replicates. All synthetic pHpG peptides exhibited inhibitory effects on human matrix metalloproteinase-1 (MMP-1). Spectroscopic analyses and molecular modelling demonstrated that pHpG peptides disrupt zinc ion coordination within the central catalytic domain of MMP-1, thereby inhibiting its enzymatic activity. As a novel peptide inhibitor of matrix metalloproteinase, pHpG-H7 modulates multiple biological processes, such as cell migration and angiogenesis, suggesting significant therapeutic potential.