2014 Results for: "Immunology"

Supplier: IMMUNOLOGY CONSULTANTS LAB MS

KIT ELISA HAMSTER CHO PLBL2 1PLATE

Supplier: IMMUNOLOGY CONSULTANTS LAB MS

ANTIBODY IGE MONOCNL HU 4F7 IGG2A 0.1MG

Supplier: IMMUNOLOGY CONSULTANTS LAB MS

PROTEIN RECOM PLBL2 HAM CHO ELISA LQ 1MG

Supplier: List Biological Laboratories, Inc.

The potent toxicity of both the botulinum neurotoxins and anthrax lethal toxin is due to a zinc-dependent proteolytic activity associated with the toxins.  Measurement of this enzymatic activity provides for both a potentially sensitive and direct means for detection of the toxin, and a method for identifying potential toxin inhibitors using high throughput screening. A highly efficient approach for monitoring enzymatic activity is based on the use of fluorescence resonance energy transfer (FRET) substrates. These fluorogenic peptides contain a donor fluorescent group at one end and a suitable chromogenic acceptor group at the other.  The fluorescence is quenched initially by intramolecular energy transfer between the donor/acceptor pair.  Cleavage of the FRET substrate by the appropriate enzyme releases the fluorophore and full fluorescence is restored.  The increase in fluorescence intensity is directly proportional to the amount of enzyme present.  Enzymatic activity can be monitored continuously by recording the increase in fluorescence intensity with time.  The change in the relative fluorescence units (RFU) as cleavage occurs can be converted to nmoles of cleaved substrate from a standard curve generated using a Calibration Peptide which is the cleaved substrate containing only the N-terminally attached fluorophore.  For Botulinum neurotoxin type A, a Control FRET peptide substrate that is not cleaved by the neurotoxin but contains all remaining non-specific sites in the sequence can be used to screen background cleavage of the substrate that can occur in complex matrices.