Recombinant Glu-C, Mass Spec Grade

• Cat.No.: Glu-C-42

Specification

• Description: Endoproteinase rGlu-C, Mass Spec Grade, is a serine proteinase that specifically cleaves peptide bonds at C-terminal to glutamic acid residues. Enzyme specificity to glutamic acid is high in ammonium bicarbonate and ammonium acetate. In phosphate buffers, cleavage occurs at both aspartic and glutamic residues. rGlu-C activity is optimal in the pH range of 4.0-9.0. This mass spec grade enzyme can be used alone or in combination with other proteases to generate protein digests.
• Form: Lyophilized in the presence of trehalose (1.65 mg/vial)
• Bio-activity: 800 U/min/mg
• Molecular Mass: 24 kDa
• Purity: > 99.5 % peak area of rGlu-C, analyzed by HPLC at 280 nm.
• Storage: Store the lyophilized powder at -4 or 20 centigrade, store reconstituted enzyme solution at -20 centigrade for up to 8 weeks.
• CAS No.: 66676-43-5
• Shelf life: 36 months at -20 centigrade
• Stability: Maximally active in the pH range of 4-9
• Usage Notes: In-Solution Protein Digestion Protocol (recommended): 1. For maximum activity, resuspend Mass Spectrum Grade rGlu-C with the double-distilled from user. 2. Dissolve protein samples with Tris-HCl (pH 8) buffer to a final protein concentration of 50 mM prior to digestion. 3. Add rGlu-C proteinase to a protein : proteinase ratio of 20: 1(w/w). Mix well and incubate at 37 centigrade for 4 h.
• Specificity: No prominent nonspecific peaks are observed by HPLC analysis after 16 hours of incubation of HSA with Glu-C compared to the 1-hour digestion
• Unit Definition: One unit is the amount of Mass spectrum Grade rGlu-C will hydrolyze 1.0 μmol of N-t-Boc--L-glutamic acid a-phenyl easter per minute at pH 7.8 at 37 centigrade, A270, and Light path=1 cm
• LC-MS/MS Analysis: Human Serum Albumin (HSA) was dissolved, denatured at 37 centigrade for 1 h, diluted at pH 8.0, and incubated with rGlu-C for 4 h. The digest was analyzed by LC-MS/MS, and peptide results matched the peptides generated in a theoretical digests of HSA by rGlu-C.
• Resuspension Buffer: Resuspend rGlu-C powder in double-distilled water from user.
• MALDI-TOF Analysis: Impurity is not found in rGlu-C proteinase analyzed by MALDI-TOF.