Native α-Chymotrypsin, Mass Spec Grade

• Cat.No.: α-Chymotrypsin-43

Specification

• Description: Chymotrypsin is a serine endoprotease that specifically cleaves the C-terminal peptide bonds of Tyr, Phe, Trp, and Leu. It also cleaves some C-terminal peptide bonds of Met, Ala, Asp, and Glu. The residual trypsin can be inactivated by TLCK and purified. The protease can be activated and stabilized by Ca2+ ions.
• Form: Lyophilized powder
• Bio-activity: 70 U/mg
• Molecular Mass: 25 kDa
• Purity: > 99.0 % peak area analyzed by HPLC at 280 nm.
• Applications: Chymotrypsin specifically hydrolyzes and denatures protein Y, F, W, and L positions.
• Storage: Store freeze-dried powder at -20 centigrade refrigerator; store dissolved enzyme at -20 centigrade, valid for 3 months.
• EC No.: EC 3.421.1
• Shelf life: Lyophilized powder 24 months at -20 centigrade.
• Usage Notes: In-Solution Protein Digestion Protocol: Use α-chymotrypsin at a protease to protein ratio of 1: 50 (w/w), and perform digestion in 100 mM Tris-HCl (pH 7.8) containing 10 mM CaCl2 at 30 centigrade for 2-12 hours. Tips: 1. The protease will self-hydrolyze if the water bath temperature is higher than 37 centigrade. 2. Preferably < 1M urea or guanidine hydrochloride concentration during the sample digestion.
• Specificity: For human serum albumin samples, > 95.0 % specificity of ESI-MS/MS for Y, F, W and L terminus.
• Unit Definition: The amount of 1.0 μmol BTEE protein hydrolyzed by chymotrypsin per minute at pH 7.8 at 25 centigrade.
• Resuspension Buffer: Reconstitute lyophilized powder in 100 μL 1 mM hydrochloric acid containing 2 μM CaCl2 (recommended).
• MALDI-TOF Analysis: No impurity protein peaks were found in the purified protease using matrix laser desorption mass spectrometry.
• pH Range: Maximally active in the pH range of 7.8.