This Diphtheria toxin was highly purified from the growth media of Corynebacterium diphtheriae strain PW8 as mostly unnicked form.
Diphtheria toxin is a single polypeptide chain of 535 amino acids (58 kD) and nicked by cellular protease like furin to give fragments A (N-terminal, 21 kDa) and B (C-terminal, 37 kDa) which are linked by disulfide bridges. Binding to the cell surface of frgment B allows fragment A to penetrate the host cell. Fragment A catalyzes the ADP-ribosylation of eucaryotic elongation factor-2 (eEF2) by using NAD as a substrate, thus inactivating eEF2 and inhibiting protein synthesis.
2`5 mg/ml (depending on lot) in 20 mM Tris-HCl (pH 7.2), 150 mM NaCl
Addition of 20 ~30 pg/ml of Diphtheria toxin in growth medium caused 50% lethality after 43 h in Vero cells. Nicking of Diphtheria toxin by trypsin by trypsin and reduction by dithiothreitol further increase the activity.
More than 95% purity by SDS-PAGE
1) Inhibition of protein synthesis in eucaryotic cells
2) Negative selection agent for ES cells in construction of transgenic mouse
3) Putative drug for treatment of malignant tumors such as leukemia
4) Antigen for Western blotting and ELISA
5) As a marker of Diphtheria toxin in SDS-PAGE
The toxin can be inactivated by exposing acids below pH 1 or pH above 12, followed by boiling for 30 min.
Ship with dry ice and store at -80centigrade.
It should be handled carefully by persons with expertise in knowledge and techniques for the safe handling of Diphtheria toxin. Avoid mouth pipetting. Wear protective gloves when handling the toxin. Avoid contact with open wounds. Wash thoroughly any area of the body that makes contact with the toxin. It is recommended that persons who handle the toxin are immunized by diphtheria vaccine.