ISSN:
1573-4935
Keywords:
diphtheria toxin fragment A
;
elongation factor 2
;
Cibacron blue
;
blue Sepharose
;
NAD
;
GTP
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract Diphtheria toxin fragment A interacts with Cibacron blue in solution, although it is not retained by blue Sepharose columns. Difference spectral titration of fragment A with the dye gives a dissociation constant of the order of 10−5 M and a 1∶1 stoichiometry for the complex. In equilibrium dialysis experiments Cibacron blue behaves as a competitive inhibitor of the binding of NAD to diphtheria toxin fragment A. The dye inhibits in a non-competitive way the fragment A-catalysed transfer of ADP-ribose from NAD to elongation factor 2 (EF2). By affinity chromatography on blue Sepharose a binding of EF2 and of ADP-ribosyl-EF2 with the dye is also demonstrated. GDP, GTP and GDP(CH2)P are able to displace EF2 from blue Sepharose.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01116867
