Devan M L, Orlova T I, Silaev A B
Antibiotiki. 1975 Mar;20(3):243-8.
Actinomycin D0 differing from actinomycin D in replacement of I residue of sarcosine by glycine in one of the peptide chains was found to have a lower inhibitory effect on RNA synthesis in various biological systems. On interaction of E. coli with DNA actinomycin D0 formed a complex with DNA having the binding constant K=1.6 with 10-5 which was 100 times lower than the binding constant of actinomycin D. Therefore, actinomycin D0 formed a complex with DNA which was 100 times less stable than actinomycin D. Actinomycins D0, D and II having different conformations in buffer on interaction with DNA formed complexes having similar conformations. The conformational change from free actinomycin to bound actinomycin was found difficult in case of actinomycin D0 because of its slow rate of complex formation with DNA as compared to that of other actinomycins complex formation with DNA.
发现肽链之一中甘氨酸取代肌氨酸的I残基的放线菌素D0，在各种生物系统中对RNA合成的抑制作用较低。在大肠杆菌与DNA相互作用时，放线菌素D0与DNA形成复合物，其结合常数K = 1.6×10⁻⁵，比放线菌素D的结合常数低100倍。因此，放线菌素D0与DNA形成的复合物比放线菌素D稳定100倍。在缓冲液中具有不同构象的放线菌素D0、D和II与DNA相互作用时形成具有相似构象的复合物。由于与其他放线菌素与DNA形成复合物的速率相比，放线菌素D0与DNA形成复合物的速率较慢，因此在放线菌素D0的情况下，从游离放线菌素到结合型放线菌素的构象变化很难发生。
