Bacillus anthracis is the etiological agent of anthrax. Major virulence factors produced by Bacillus anthracis are the gamma-linked, poly-D-glutamic acid capsule and an exotoxin composed of three components, protective antigen (PA), lethal factor (LF), and edema factor (EF). These proteins are not toxic separately but act in binary combinations. The complex of PA, the cell binding component, with LF, one of the enzymatic moieties, is termed “lethal toxin” and can cause death. PA and the enzymatic EF together cause skin edema. After secretion, PA is cleaved by membrane peptidases, allowing the 63kD carboxy terminal fragment to oligomerize to a heptamer. Cleavage is an essential step in exposing the binding sites for EF and LF. The assembled PA complex and associated LF or EF enters the cell through endocytosis. PA mediates the transfer of LF and EF to the cytoplasm where these enzymes recognize and proteolyze their targets. The LF component, a zinc-dependent metalloprotease, cleaves the mitogen-activated protein kinase kinase (MAPKK), impairing its function and thereby blocking the MAPK signaling pathway. EF is a calmodulin-dependent adenylate cyclase which creates in the cell excess amounts of cyclic-AMP, resulting in edema. Current research is focused on the development of an effective vaccine as well as screening for potent inhibitors of the LF enzymatic activity.
Source:Recombinant protein corresponding to Bacillus anthracis Edema Factor.
Molecular Weight:~89kD
Biological Activity:The enzymatic activity of edema factor is assessed in a cell free system by measuring cAMP formation from ATP. The activity of this EF lot is ~1150uM cAMP/min/mg protein. The potency of EF to raise cAMP levels in Chinese hamster ovary (CHO) cells is tested in the presence of 1ug/ml PA by the method of Kumar, et al. The effective concentration 50% (EC50) of this EF lot meets specifications.
Endotoxin:≤0.1EU/mg (LAL)
Recommended Dilutions:For tissue culture applications, medium containing glutamine must be fresh. Ammonium ion released when glutamine breaks down may prevent acidification of the endosome thereby inhibiting translocation of LF or EF into the cytosol. A stable form of glutamine may be used
Optimal dilutions to be determined by the researcher.
Storage and Stability:Lyophilized and reconstituted products are stable for 6 months after receipt at -20°C. Reconstitute with sterile ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
仕様
Size：100ug
Source Antigen：Recombinant
Grade：Highly Purified
Purity：≥95% (SDS-PAGE)
Form：Supplied as a lyophilized powder in 5mM HEPES, 50mM sodium chloride, pH 7.5. Reconstitute with 100ul sterile ddH2O. Handle gently. Do not vortex.
