Biological Activity of Heated Diphtheria Toxin
نویسندگان
چکیده
منابع مشابه
Studies of the Activity of Diphtheria Toxin
It has been demonstrated that a saturating dose of diphtheria toxin produced a 90% inhibition of polio-virus replication in HeLa cells. This inhibition was reflected in infectious viral RNA synthesis and in mature virus production. Toxin had no direct effect on virus particles or I-RNA, and poliovirus adsorption and eclipse appeared to be carried out normally in intoxicated cells. When toxin wa...
متن کاملStructure-activity relationships in diphtheria toxin.
The intact diphtheria toxin molecule, a single polypeptide chain of about 62,000 daltons, has no enzymic activity. However, the transfer in uifro of ADP-ribose from NAD to aminoacyltrensferase II can be catalyzed by any of several fragments of toxin. The smallest active fragment (A, 24,000 daltons) is normally connected to the remainder of the molecule (B, 38,000 daltons) by a peptide bond and ...
متن کاملCharacterization of the deoxyribonuclease activity of diphtheria toxin.
Having discovered that the A domain of diphtheria toxin exhibits intrinsic nuclease activity (Chang, M. P., Baldwin, R. L., Bruce, B., and Wisnieski, B. J. (1989) Science 246, 1165-1168), we proceeded to examine the requirements for optimal enzymic expression. In vitro assays with linear double-stranded DNA demonstrated that optimal activity occurs at pH 7.5 and 37 degrees C. A characterization...
متن کاملCharacterization of serum anti-diphtheria antibody activity following administration of equine anti-toxin for suspected diphtheria
There is a global shortage of equine-derived diphtheria anti-toxin (DAT) for diphtheria treatment. There are few existing data on serum antibody concentrations and neutralizing activity post-treatment to support development of new therapeutics. Antibody concentrations were quantified by ELISA and anti-toxin neutralizing activity by cytotoxicity assay in serum from 4 patients receiving DAT for s...
متن کاملDiphtheria Toxin In
Recent studies have demonstrated that diphtheria toxin is an enzyme of unusual type. Small amounts of the toxin, added to nicotinamide adenine dinucleotide (NAD)-containing mammalian cell extracts, block peptide-bond formation by catalyzing inactivation of the translocating enzyme, aminoacyltransferase 2 (T2) (1-3). This highly specific reaction involves the splitting of NAD with liberation of ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Bacteriology
سال: 1973
ISSN: 0021-9193,1098-5530
DOI: 10.1128/jb.115.1.277-283.1973