"Back door" opening implied by the crystal structure of a carbamoylated acetylcholinesterase.Bartolucci, C., Perola, E., Cellai, L., Brufani, M., Lamba, D.
(1999) Biochemistry 38: 5714-5719
- PubMed: 10231521
- DOI: 10.1021/bi982723p
- Also Cited By: 2BAG
- PubMed Abstract:
- Synthesis and Structure-Activity Relationships of New Acetylcholinesterase Inhibitors: Morpholinoalkylcarbamoyloxyeseroline Derivatives
Alisi, M.A.,Brufani, M.,Filocamo, L.,Gostoli, G.,Licandro, E.,Cesta, M.C.,Lappa, S.,Marchesini, D.,Pagella, P.
(1995) Bioorg.Med.Chem.Lett. 5: 2077
- Effects of Mf-268, a New Cholinesterase Inhibitor, on Acetylcholine and Biogenic Amines in Rat Cortex
Zhu, X.D.,Cuadra, G.,Brufani, M.,Maggi, T.,Pagella, P.G.,Williams, E.,Giacobini, E.
(1996) J.Neurosci.Res. 43: 120
- Long Chain Analogs of Physostigmine as Potential Drugs for Alzheimer'S Disease: New Insights Into the Mechanism of Action in the Inhibition of Acetylcholinesterase
Perola, E.,Cellai, L.,Lamba, D.,Filocamo, L.,Brufani, M.
(1997) Biochim.Biophys.Acta 1343: 41
- Atomic Structure of Acetylcholinesterase from Torpedo Californica: A Prototypic Acetylcholine-Binding Protein
Sussman, J.L.,Harel, M.,Frolow, F.,Oefner, C.,Goldman, A.,Toker, L.,Silman, I.
(1991) Science 253: 872
The crystal structure of Torpedo californica (Tc) acetylcholinesterase (AChE) carbamoylated by the physostigmine analogue 8-(cis-2,6-dimethylmorpholino)octylcarbamoyleseroline (MF268) is reported at 2.7 A resolution. In the X-ray structure, the dimet ...
The crystal structure of Torpedo californica (Tc) acetylcholinesterase (AChE) carbamoylated by the physostigmine analogue 8-(cis-2,6-dimethylmorpholino)octylcarbamoyleseroline (MF268) is reported at 2.7 A resolution. In the X-ray structure, the dimethylmorpholinooctylcarbamic moiety of MF268 is covalently bound to the catalytic serine, which is located at the bottom of a long and narrow gorge. The alkyl chain of the inhibitor fills the upper part of the gorge, blocking the entrance of the active site. This prevents eseroline, the leaving group of the carbamoylation process, from exiting through this path. Surprisingly, the relatively bulky eseroline is not found in the crystal structure, thus implying the existence of an alternative route for its clearance. This represents indirect evidence that a "back door" opening may occur and shows that the release of products via a "back door" is a likely alternative for this enzyme. However, its relevance as far as the mechanism of substrate hydrolysis is concerned needs to be established. This study suggests that the use of properly designed acylating inhibitors, which can block the entrance of catalytic sites, may be exploited as a general approach for investigating the existence of "back doors" for the clearance of products.
Istituto di Strutturistica Chimica "G. Giacomello", CNR, Rome, Italy.