KIDGYPVDYWNCKRICWYNNKYCNDLCKGLKADSGYCWGWTLSCYCQGLPDNARIKRSGRCRA
Kurtoxin
Tx3-1 _____AECAAVYERCGKGYKRCCEERPCKCNIVMDNCTCKKFISE O76200
Tx3-2 _____ ACAGLYKKCGKGASPCCEDRPCKCDLAMGNCICK O76201
Tx3-3 _____GCANAYKSCNGPHTCCWGYNGYKKACICSGXNWK P81789
Tx3-4 _____SCINVGDFCDGKKDDCQCCRDNAFCSCSVIFGYKTNCR P81790
__________CEVGTTATSYGICMAKHKCGRQTTCTKPCLSKRCKKNH
Tx3-6 _____ACIPRGEICTDDCECCGCDNQCYCPPGSSLGIFKCSCAHANKYFCNRKKEKCKKA P81792
PRTx3-7 ___ACAGLYKKCGKGVNTCCENRPCKCDLAMGNCICKKKFVEFFGG P83911
Tx3-2 _____ ACAGLYKKCGKGASPCCEDRPCKCDLAMGNCICK O76201
Tx3-3 _____GCANAYKSCNGPHTCCWGYNGYKKACICSGXNWK P81789
Tx3-4 _____SCINVGDFCDGKKDDCQCCRDNAFCSCSVIFGYKTNCR P81790
__________CEVGTTATSYGICMAKHKCGRQTTCTKPCLSKRCKKNH
Tx3-6 _____ACIPRGEICTDDCECCGCDNQCYCPPGSSLGIFKCSCAHANKYFCNRKKEKCKKA P81792
PRTx3-7 ___ACAGLYKKCGKGVNTCCENRPCKCDLAMGNCICKKKFVEFFGG P83911
ω−Conotoxins CVID, GVIA, MVIIA, MVIIC and SVIB.
Tx3-3 (also named ω-PnTx3-3) revealed that its effect on blocking glutamate and acetylcholine release is additive to that of ω-agatoxin IVA. In brain cortical synaptosomes, Tx3-3 blocks P/Q-type calcium channels with an IC50 of 0.9 nM
electrophysiology experiments show that Tx3-3 also blocks P/Q- and R-type currents in cerebellar granule cells with an IC50 of 12 nM
Another sub-fraction of PhTx3 called Tx3-4 or ω-Phonetoxin IIA also blocks P/Q-type calcium channels in brain synaptosomes with an IC50 of 7.9 nM
electrophysiology experiments show that Tx3-3 also blocks P/Q- and R-type currents in cerebellar granule cells with an IC50 of 12 nM
Another sub-fraction of PhTx3 called Tx3-4 or ω-Phonetoxin IIA also blocks P/Q-type calcium channels in brain synaptosomes with an IC50 of 7.9 nM
Tx3-4 inhibits calcium channels coupled to KCl-induced exocytosis of synaptic vesicles with an IC50 of 1.1 nM and that the P/Q-type calcium channels are the main target of the toxin
is not a very selective toxin. It is a 74 amino acid peptide toxin with a sequence containing 12 cysteines isolated from the venom of Filista hibernalis
IC50s of 50 nM and 150 nM were recorded for ProTx-I and II, respectively. To summarize, it seems that the toxin-channel interaction surface should be similar in these sodium and calcium channel subtypes.
Filistatoxin peptidic sequence.
ProTx-I__________ECRYWLGGCSAGQTCCKHLVCSRRHGWCVWDGTFS
ProTx-II___________YCQKWMWTCDSERKCCEGMVCRLWCKKKLW
ProTx-II___________YCQKWMWTCDSERKCCEGMVCRLWCKKKLW
ω-FLTX-Kh1a _____AECLMIGDTSCVPRLGRRCCYGAWCYCDQQLSCRRVGRKRECGWVEVNCKCGWSWSQRIDDWRADYSCKCPEDQ P60979
Two peptides, ProTx-I and ProTx-II, from the venom of the green velvet tarantula Thrixopelma pruniens, have been isolated and characterized
[Peptide Neurotoxins that Affect Voltage-Gated Calcium Channels: A Close-Up on ω-Agatoxins]
Selection 1
Selection 2
Selection 3
Stability lg(cond(W))
lg[Kd]
(delta)G
T(delta)S
