TY - JOUR A1 - Dietz, Gerhard A1 - Woenckhaus, Christoph A1 - Jaenicke, Rainer A1 - Schuster, Inge T1 - Modifizierung von Glycerinaldehyd-3-phosphat-Dehydrogenase aus Kaninchen-Skelettmuskel mit dem Coenzymanalogen [3-(3-Bromacetylpyridinio)-propyl]-adenosin-pyrophosphat T1 - Modification of glyceraldehyde-3-phosphate dehydrogenase from rabbit skeletal muscle by [3-(3-Bromoacetylpyridinio)-propyl]-adenosine pyrophosphate T2 - Zeitschrift für Naturforschung, C N2 - The NAD analogue [3-(3-acetylpyridinio)-propyl] adenosine pyrophosphate forms enzymically inactive complexes with glyceraldehyde-3-phosphate dehydrogenase from yeast and rabbit skeletal muscle. In the latter enzyme four mol of the analogue are bound with equal affinity inhibiting the enzyme in a competitive way: KI = 0.3 mM as compared to the dissociation constant KD=O.6 mм. The brominated derivative [3- (3-bromoacetylpyridinio) -propyl] adenosine pyrophosphate is co­valently bound to both enzymes causing irreversible loss of enzymic activity. Complete inactivation of the enzyme from muscle requires two moles of the analogue per mol of tetramer. The remaining two sites are still able to bind two mol of NAD+ without regain of enzymic activity. In the case of the yeast enzyme four mol of the analogue are bound. Inactivation of the rabbit muscle enzyme is accompanied by the disappearance of two out of four highly reactive sulfhydryl groups; in the yeast enzyme the four active site cysteine residues are still able to react with DTNB1 the reactivity being diminished significantly. Hybrid formation between the native enzymes from yeast and skeletal muscle is not affected by the modification of the enzyme. Similarly the sedimentation properties of the covalently modi­fied enzyme are indistinguishable from those of the native molecule. This indicates that both the native and the irreversibly inhibited enzyme are identical regarding their quaternary structure. KW - Affinity Labeling KW - Glyceraldehyde-3-phosphate Dehydrogenase KW - Hybrid Formation Y1 - 2014 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/72034 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-720347 SN - 0939-5075 SN - 1865-7125 VL - 32.1977 IS - 1-2 SP - 85 EP - 92 PB - Verlag der Zeitschrift für Naturforschung CY - Tübingen ER -