Developing a peptide-based near-infrared molecular probe for protease sensing

Bioconjug Chem. 2004 Nov-Dec;15(6):1403-7. doi: 10.1021/bc049924s.

Abstract

Recently near-infrared (NIR) molecular probes have become important reporter molecules for a number of types of in vivo biomedical imaging. A peptide-based NIR fluorescence probe consisting of a NIR fluorescence emitter (Cy5.5), a NIR fluorescence absorber (NIRQ820), and a protease selective peptide sequence was designed to sense protease activity. Using a MMP-7 model, we showed that NIRQ820 efficiently absorbs the emission energy of Cy5.5 resulting in a low initial signal. Upon reacting with its target, MMP-7, the fluorescence signal of the designed probe was increased by 7-fold with a K(cat)/K(m) of 100 000 M(-)(1) s(-)(1). The described synthetic strategy should have wide application for other NIR probe preparations.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Humans
  • Matrix Metalloproteinase 7
  • Metalloendopeptidases / metabolism*
  • Mice
  • Mice, Nude
  • Molecular Probes / metabolism*
  • Peptide Fragments / chemistry
  • Peptide Fragments / metabolism*
  • Peptide Hydrolases / metabolism
  • Spectroscopy, Near-Infrared / methods*

Substances

  • Molecular Probes
  • Peptide Fragments
  • Peptide Hydrolases
  • Metalloendopeptidases
  • MMP7 protein, human
  • Matrix Metalloproteinase 7