Search results
Results from the WOW.Com Content Network
Diphtheria toxin is a single polypeptide chain of 535 amino acids consisting of two subunits linked by disulfide bridges, known as an A-B toxin.Binding to the cell surface of the B subunit (the less stable of the two subunits) allows the A subunit (the more stable part of the protein) to penetrate the host cell.
The diphtheria toxin precursor is a protein of molecular weight 60 kDa. Certain proteases, such as trypsin, selectively cleave DT to generate two peptide chains, amino-terminal fragment A (DT-A) and carboxyl-terminal fragment B (DT-B), which are held together by a disulfide bond . [ 23 ]
Diphtheria vaccine is a toxoid vaccine against diphtheria, an illness caused by Corynebacterium diphtheriae. [2] Its use has resulted in a more than 90% decrease in number of cases globally between 1980 and 2000. [ 3 ]
The diphtheria toxin gene is encoded by the bacteriophage found in toxigenic strains, integrated into the bacterial chromosome. [13] The diphtheria toxin repressor is mainly controlled by iron. It serves as the essential cofactor for the activation of target DNA binding. A low concentration of iron is required in the medium for toxin production.
Map of the historical and current Iditarod trails; the route taken during the 1925 serum run is shown in green.. The 1925 serum run to Nome, also known as the Great Race of Mercy and The Serum Run, was a transport of diphtheria antitoxin by dog sled relay across the US territory of Alaska by 20 mushers and about 150 sled dogs across 674 miles (1,085 km) in 5 + 1 ⁄ 2 days, saving the small ...
The vaccine components include diphtheria and tetanus toxoids, and either killed whole cells of the bacterium that causes pertussis or pertussis antigens. The term toxoid refers to vaccines which use an inactivated toxin produced by the pathogen which they are targeted against to generate an immune response.
CRM197 is a genetically detoxified form of diphtheria toxin. A single mutation at position 52, substituting glutamic acid for glycine, causes the ADP-ribosyltransferase activity of the native toxin to be lost. The structural basis for the lack of CRM197 toxicity has recently been elucidated. [4]
Diphtheria antitoxin (DAT) is a medication made up of antibodies used in the treatment of diphtheria. [1] [2] It is no longer recommended for prevention of diphtheria. [2] [3] It is administered through injection into a vein or muscle. [2] Side effects are common. [3] They include serum sickness and allergic reactions including anaphylaxis. [2]