EI (P00050) Protein Card

General Information

Name	EI
Organism	Conus ermineus (Atlantic fish-hunting cone)
Organism region	Eastern Atlantic and Mediterranean,Western Atlantic and Caribbean
Organism diet	piscivorous
Protein Type	Wild type
Protein precursor	EI precursor (3000)

Classification

Sequence

RDOCCYHPTCNMSNPQIC(nh2)

Modified residues

position	symbol	name
3	O	4-Hydroxyproline
19	nh2	C-term amidation

Sequence evidence

protein level

Average Mass

2093.36

Monoisotopic Mass

2091.78

Isoelectric Point

7.98

Extinction Coefficient [280nm]

1490.00

Activity

IC50: Nicotinic acetylcholine receptors

Target	Organism	IC50		n_hill	Agonist	Ref
α1β1δε	M. musculus	65.9 nM	[58.5-74.2]	1.3	ACh(10 uM)	Ning,J. et al. (2019)
α1β1γδ	Unknown	0.37nM	+/-0.23	0.46	50uM nicotine	López-Vera,E. et al. (2007)
α3β2	R. norvegicus	7297 nM	[3748-14200]	0.8	ACh(100 uM)	Ning,J. et al. (2019)
α3β4	R. norvegicus	6444 nM	[5443-7628]	1.4	ACh(100 uM)	Ning,J. et al. (2019)

Percentage inhibition: Nicotinic acetylcholine receptors

Target	Organism	% inhibition	Concentration	Agonist	Ref
α1β1γδ	Unknown	40	10uM	50uM nicotine	López-Vera,E. et al. (2007)
α3β4	Unknown	0	10uM	50uM nicotine	López-Vera,E. et al. (2007)
α4β2	Unknown	55	10uM	50uM nicotine	López-Vera,E. et al. (2007)

Synthetic variants

References

Martinez,J.S., Olivera,B.M., Gray,W.R., Craig,A.G., Groebe,D.R., Abramson,S.N. and McIntosh,J.M. (1995) alpha-Conotoxin EI, a new nicotinic acetylcholine receptor antagonist with novel selectivity Biochemistry 34:14519-14526

Park,K.H., Suk,J.E., Jacobsen,R., Gray,W.R., McIntosh,J.M. and Han,K.H. (2001) Solution conformation of alpha-conotoxin EI, a neuromuscular toxin specific for the alpha 1/delta subunit interface of torpedo nicotinic acetylcholine receptor J. Biol. Chem. 276:49028-49033

López-Vera,E., Aguilar,M.B., Schiavon,E., Marinzi,C., Ortiz,E., Restano Cassulini,R., Batista,C.V., Possani,L.D., Heimer de la Cotera,E.P., Peri,F., Becerril,B. and Wanke,E. (2007) Novel alpha-conotoxins from Conus spurius and the alpha-conotoxin EI share high-affinity potentiation and low-affinity inhibition of nicotinic acetylcholine receptors. FEBS J. 274:3972-3985

Ning,J., Ren,J., Xiong,Y., Wu,Y., Zhangsun,M., Zhangsun,D., Zhu,X. and Luo,S. (2019) Identification of Crucial Residues in α-Conotoxin EI Inhibiting Muscle Nicotinic Acetylcholine Receptor Toxins (Basel) 11:603

Internal links

Protein Precursor	EI precursor (3000)
Nucleic acids
Structure	NMR STRUCTUE OF ALPHA-CONOTOXIN EI

External links

UniProtKB/Swiss-Prot	P50982
Ncbi	1K64_A, P50982

Tools