Biomaterial Database

Noncompetitive inhibition by aluminum, scandium and yttrium of acetylcholinesterase from Electrophorus electricus. 1982

J K Marquis, and A J Lerrick

Measurements of altered activity of soluble acetylcholinesterase from E. electricus electric organ by the inorganic cations aluminum, scandium and yttrium demonstrate that these ions are noncompetitive enzyme inhibitors. Al3+ inhibited enzyme activity at all substrate and inhibitor concentrations studied. Inhibition by Al3+ did not appear to be sensitive to the active site-specific, competitive ligand physostigmine or to calcium, a peripheral site-binding activator cation. Inhibition by another peripheral site-binding noncompetitive inhibitor, decamethonium, was not altered by Al3+. Al3+ appears thus to have interacted with a class of peripheral anionic sites on AChE distinct from the beta- or P1 peripheral anionic sites that bind Ca2+ and C-10 and may be a useful probe of a subclass of gamma- or P2-4 peripheral anionic sites. A possible mechanism for Al3+ neurotoxicity, via alterations of the enzymes of cholinergic neurotransmission, is also suggested.

UI	MeSH Term	Description	Entries
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D002800	Cholinesterase Inhibitors	Drugs that inhibit cholinesterases. The neurotransmitter ACETYLCHOLINE is rapidly hydrolyzed, and thereby inactivated, by cholinesterases. When cholinesterases are inhibited, the action of endogenously released acetylcholine at cholinergic synapses is potentiated. Cholinesterase inhibitors are widely used clinically for their potentiation of cholinergic inputs to the gastrointestinal tract and urinary bladder, the eye, and skeletal muscles; they are also used for their effects on the heart and the central nervous system.	Acetylcholinesterase Inhibitor,Acetylcholinesterase Inhibitors,Anti-Cholinesterase,Anticholinesterase,Anticholinesterase Agent,Anticholinesterase Agents,Anticholinesterase Drug,Cholinesterase Inhibitor,Anti-Cholinesterases,Anticholinesterase Drugs,Anticholinesterases,Cholinesterase Inhibitors, Irreversible,Cholinesterase Inhibitors, Reversible,Agent, Anticholinesterase,Agents, Anticholinesterase,Anti Cholinesterase,Anti Cholinesterases,Drug, Anticholinesterase,Drugs, Anticholinesterase,Inhibitor, Acetylcholinesterase,Inhibitor, Cholinesterase,Inhibitors, Acetylcholinesterase,Inhibitors, Cholinesterase,Inhibitors, Irreversible Cholinesterase,Inhibitors, Reversible Cholinesterase,Irreversible Cholinesterase Inhibitors,Reversible Cholinesterase Inhibitors
D004553	Electric Conductivity	The ability of a substrate to allow the passage of ELECTRONS.	Electrical Conductivity,Conductivity, Electric,Conductivity, Electrical
D004557	Electric Organ	In about 250 species of electric fishes, modified muscle fibers forming disklike multinucleate plates arranged in stacks like batteries in series and embedded in a gelatinous matrix. A large torpedo ray may have half a million plates. Muscles in different parts of the body may be modified, i.e., the trunk and tail in the electric eel, the hyobranchial apparatus in the electric ray, and extrinsic eye muscles in the stargazers. Powerful electric organs emit pulses in brief bursts several times a second. They serve to stun prey and ward off predators. A large torpedo ray can produce of shock of more than 200 volts, capable of stunning a human. (Storer et al., General Zoology, 6th ed, p672)	Electric Organs,Organ, Electric,Organs, Electric
D004593	Electrophorus	A genus of fish, in the family GYMNOTIFORMES, capable of producing an electric shock that immobilizes fish and other prey. The species Electrophorus electricus is also known as the electric eel, though it is not a true eel.	Eel, Electric,Electric Eel,Electrophorus electricus
D000535	Aluminum	A metallic element that has the atomic number 13, atomic symbol Al, and atomic weight 26.98.	Aluminium,Aluminium-27,Aluminum-27,Aluminium 27,Aluminum 27
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D012538	Scandium	An element of the rare earth family of metals. It has the atomic symbol Sc, atomic number 21, and atomic weight 45.
D015019	Yttrium	An element of the rare earth family of metals. It has the atomic symbol Y, atomic number 39, and atomic weight 88.91. In conjunction with other rare earths, yttrium is used as a phosphor in television receivers and is a component of the yttrium-aluminum garnet (YAG) lasers.