Alcalase, an endoproteinase
, can hydrolyze proteins to peptides possessing hydrophobic amino acids at the end of their peptide chains.
1 g/L glutamyl endoproteinase
Lethal factor (LF) toxemia was quantified at CDC's Clinical Chemistry Branch, Division of Laboratory Sciences (Atlanta, GA, USA), by using a validated mass spectrometry method that reports specific LF endoproteinase
activity in nanograms per milliliter of serum.
20) Briefly, the protein pellets left after RNA isolation were reconstituted, reduced with Tris(2-carboxyethyl)phosphine, and digested successively with cyanogen bromide, endoproteinase
Lys-C, and trypsin.
5 mg) was reduced by dithiothreitol, S-carbox-amidom ethylated and digested with endoproteinase
C (substrate:enzyme = 50:1, w/w) in 40 [micro]l of 10 mM Tris- HCl (pH 7.
Peptide mapping and evaluation of glycopeptide microheterogeneity derived from endoproteinase
digestion of erythropoietin by affinity high-performance capillary electrophoresis.
Next, the hemolysate is incubated with the endoproteinase
Glu-C for 18 hours at 37[degrees]C to cleave Hb into peptides, whereby the specific glycated and non-glycated N-terminal peptides of the [beta]-chain of Hb are measured by either capillary electrophoresis or electrospray ionization mass spectrometry.
Amin I, Jinap S, Jamilah B (1998) Proteolytic activity (aspartic endoproteinase
and carboxypeptidase) of cocoa bean during fermentation.
4]-labeled sample was then subjected to proteolytic digestion with endoproteinase
Asp-N, which cleaves at aspartic acid residues, or aminopeptidase I, which nonspecifically removes amino acid residues inwards from N-terminus, for I hour at room temperature and followed by immunoprecipitation.
95 units of carboxypeptidase B (Sigma), 2 units of endoproteinase
glu-C (Boehringer-Mannheim), or 1.
In brief, the N-terminal hexapeptide of the hemoglobin [beta] chain is enzymatically cleaved by the proteolytic enzyme endoproteinase
Glu-C before analysis.
activity was quantified by using mass spectrometry (3).