Proteolytic stability of beta-peptide bonds probed using quenched fluorescent substrates incorporating a hemoglobin cleavage site.

FEBS letters

PubMedID: 12560099

Gopi HN, Ravindra G, Pal PP, Pattanaik P, Balaram H, Balaram P. Proteolytic stability of beta-peptide bonds probed using quenched fluorescent substrates incorporating a hemoglobin cleavage site. FEBS Lett. 2003;535(1-3):175-8.
A set of designed internally quenched fluorescence peptide substrates has been used to probe the effects of insertion of beta-peptide bonds into peptide sequences. The test sequence chosen corresponds to a proteolytically susceptible site in hemoglobin alpha-chain, residues 32-37. Fluorescence and mass spectral measurements demonstrate that the insertion of an beta-residues at the potential cleavage sites completely abolishes the action of proteases; in addition, the rate of cleavage of the peptide bond preceding the site of modification is also considerably reduced.