Controlled proteolysis of mouse epidermal growth factor. An RP-HPLC and 1H-n.m.r. study.
Tryptic digestion of the mouse epidermal growth factor (mEGF) and the chromatographic separation of its proteolytic fragments by RP-HPLC affords the isolation of the pure hormone, of its 1-48 (Des(49-53)mEGF) and 1-45 (Des(46-53)mEGF) derivatives, and of the carboxyl-terminal pentapeptide W49-W50-E51-L52-R53. Kinetics of mEGF proteolytic degradation follows a two-state time-course: native mEGF being converted into Des(49-53)mEGF with an apparent half-time of 10 min; and Des(49-53)mEGF subsequently hydrolyzed to Des(46-53)mEGF with an apparent half-time of 7 h. Native mEGF and its proteolytic fragments have been characterized by 1H-n.m.r. spectroscopy. In the aromatic and aliphatic regions, the 1H-n.m.r. spectrum proved to be a sufficiently sensitive probe for following controlled proteolysis, and for analyzing the influence of the carboxyl-terminal sequence on the hormone conformation and stability.
Menegatti
E
E
Department of Pharmaceutical Sciences, University of Ferrara, Italy.
Scalia
S
S
Bortolotti
F
F
Ascenzi
P
P
De Marco
A
A
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004815:Epidermal Growth Factor / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D010446:Peptide Fragments / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism
D010446:Peptide Fragments; D004815:Epidermal Growth Factor; D010447:Peptide Hydrolases; D014357:Trypsin