(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Metazoa: NE > Eumetazoa: NE > Bilateria: NE > Deuterostomia: NE > Chordata: NE > Craniata: NE > Vertebrata: NE > Gnathostomata: NE > Teleostomi: NE > Euteleostomi: NE > Sarcopterygii: NE > Dipnotetrapodomorpha: NE > Tetrapoda: NE > Amniota: NE > Sauropsida: NE > Sauria: NE > Lepidosauria: NE > Squamata: NE > Bifurcata: NE > Unidentata: NE > Episquamata: NE > Toxicofera: NE > Serpentes: NE > Colubroidea: NE > Elapidae: NE > Bungarinae: NE > Bungarus: NE > Bungarus fasciatus: NE
G122H/Y124Q/S125T : Mutant of Bungarus fasciatus acetylcholinesterase with low affinity and low hydrolase activity toward organophosphorus esters K285D : Cloning and expression of acetylcholinesterase from Bungarus fasciatus venom. A new type of cooh-terminal domain; involvement of a positively charged residue in the peripheral site M70Y/K285D : Cloning and expression of acetylcholinesterase from Bungarus fasciatus venom. A new type of cooh-terminal domain; involvement of a positively charged residue in the peripheral site M70Y : Cloning and expression of acetylcholinesterase from Bungarus fasciatus venom. A new type of cooh-terminal domain; involvement of a positively charged residue in the peripheral site Y330A : Substrate activation in acetylcholinesterase induced by low pH or mutation in the pi-cation subsite Y330G : Substrate activation in acetylcholinesterase induced by low pH or mutation in the pi-cation subsite Y330W : Substrate activation in acetylcholinesterase induced by low pH or mutation in the pi-cation subsite
1 structure: 4QWW: Crystal structure of snake venom acetylcholinesterase in complex with inhibitory antibody fragment Fab410 bound at the peripheral site Kinetic: bunfa-ACHE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MPSCQPGKMPAPWPWWLQLLLCIPSCVAVLPGRAGELKVSTQTGSVRGLS LPVLDGHVSAFLGIPFAEPPLGRMRFLRPEPVKPWQHVLDATSYKPACYQ MVDTSYPGFQGTEMWNPNRGMSEDCLYLNIWVPSPRPKDAPVLVWIYGGG FYSGAASLDVYDGRFLTYTQNVILVSLSYRVGAFGFLGLPGSPEAPGNMG LLDQRLALQWIQNNIHPFGGNPRAVTVFGESAGAASVGMHLLSTQSRTLF QRAILQSGGPNAPWATVTPAESRGRAALLGKQLGCHFNNDSELVSCLRSK NPQELIDEEWSVLPYKSIFRFPFVPVIDGDFFPDTPEAMLSSGNFKETQV LLGVVKDEGSYFLIYGLPGFSKDNESLISRADFLEGVRMSVPHANDIATD AVVLQYTDWQDQDNREKNREALDDIVGDHNVICPVVQFANDYAKRNSKVY AYLFDHRASNLLWPPWMGVPHGYEIEFVFGLPLNDSLNYTPQEKELSRRM MRYWANFARTGNPTDPADKSGAWPTYTASQPQYVQLNTQPLATQPSLRAQ ICAFWNHFLPKLLNATVDPPRADRRRRSARA
References
Title: Crystal Structure of Snake Venom Acetylcholinesterase in Complex with Inhibitory Antibody Fragment Fab410 Bound at the Peripheral Site: EVIDENCE FOR OPEN AND CLOSED STATES OF A BACK DOOR CHANNEL Bourne Y, Renault L, Marchot P Ref: Journal of Biological Chemistry, 290:1522, 2015 : PubMed
The acetylcholinesterase found in the venom of Bungarus fasciatus (BfAChE) is produced as a soluble, non-amphiphilic monomer with a canonical catalytic domain but a distinct C terminus compared with the other vertebrate enzymes. Moreover, the peripheral anionic site of BfAChE, a surface site located at the active site gorge entrance, bears two substitutions altering sensitivity to cationic inhibitors. Antibody Elec410, generated against Electrophorus electricus acetylcholinesterase (EeAChE), inhibits EeAChE and BfAChE by binding to their peripheral sites. However, both complexes retain significant residual catalytic activity, suggesting incomplete gorge occlusion by bound antibody and/or high frequency back door opening. To explore a novel acetylcholinesterase species, ascertain the molecular bases of inhibition by Elec410, and document the determinants and mechanisms for back door opening, we solved a 2.7-A resolution crystal structure of natural BfAChE in complex with antibody fragment Fab410. Crystalline BfAChE forms the canonical dimer found in all acetylcholinesterase structures. Equally represented open and closed states of a back door channel, associated with alternate positions of a tyrosine phenol ring at the active site base, coexist in each subunit. At the BfAChE molecular surface, Fab410 is seated on the long Omega-loop between two N-glycan chains and partially occludes the gorge entrance, a position that fully reflects the available mutagenesis and biochemical data. Experimentally based flexible molecular docking supports a similar Fab410 binding mode onto the EeAChE antigen. These data document the molecular and dynamic peculiarities of BfAChE with high frequency back door opening, and the mode of action of Elec410 as one of the largest peptidic inhibitors targeting the acetylcholinesterase peripheral site.
Title: Cloning and expression of acetylcholinesterase from Bungarus fasciatus venom. A new type of cooh-terminal domain; involvement of a positively charged residue in the peripheral site Cousin X, Bon S, Duval N, Massoulie J, Bon C Ref: Journal of Biological Chemistry, 271:15099, 1996 : PubMed
As deduced from cDNA clones, the catalytic domain of Bungarus fasciatus venom acetylcholinesterase (AChE) is highly homologous to those of other AChEs. It is, however, associated with a short hydrophilic carboxyl-terminal region, containing no cysteine, that bears no resemblance to the alternative COOH-terminal peptides of the GPI-anchored molecules (H) or of other homomeric or heteromeric tailed molecules (T). Expression of complete and truncated AChE in COS cells showed that active hydrophilic monomers are produced and secreted in all cases, and that cleavage of a very basic 8-residue carboxyl-terminal fragment occurs upon secretion. The COS cells produced Bungarus AChE about 30 times more efficiently than an equivalent secreted monomeric rat AChE. The recombinant Bungarus AChE, like the natural venom enzyme, showed a distinctive ladder pattern in nondenaturing electrophoresis, probably reflecting a variation in the number of sialic acids. By mutagenesis, we showed that two differences (methionine instead of tyrosine at position 70; lysine instead of aspartate or glutamate at position 285) explain the low sensitivity of Bungarus AChE to peripheral site inhibitors, compared to the Torpedo or mammalian AChEs. These results illustrate the importance of both the aromatic and the charged residues, and the fact that peripheral site ligands (propidium, gallamine, D-tubocurarine, and fasciculin 2) interact with diverse subsets of residues.
Bungarus fasciatus (Banded krait) (Pseudoboa fasciata) acetylcholinesterase
