2crd: Difference between revisions
New page: left|200px<br /> <applet load="2crd" size="450" color="white" frame="true" align="right" spinBox="true" caption="2crd" /> '''ANALYSIS OF SIDE-CHAIN ORGANIZATION ON A RE... |
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'''ANALYSIS OF SIDE-CHAIN ORGANIZATION ON A REFINED MODEL OF CHARYBDOTOXIN: STRUCTURAL AND FUNCTIONAL IMPLICATIONS'''<br /> | '''ANALYSIS OF SIDE-CHAIN ORGANIZATION ON A REFINED MODEL OF CHARYBDOTOXIN: STRUCTURAL AND FUNCTIONAL IMPLICATIONS'''<br /> | ||
==Overview== | ==Overview== | ||
The spatial organization of side chains on a refined model of | The spatial organization of side chains on a refined model of charybdotoxin is presented. First, the structural role of two groups of well-defined, low-accessible side chains (Thr3, Val5, Val16, Leu20, Cys33 and Leu20, His21, Thr23, Cys17, Cys35) is discussed. These side chains are conserved in three out of the five known scorpion toxins acting on K+ channels. Interestingly, they are not conserved in scyllatoxin which presents a slightly different secondary structure organization. Second, the spatial organization of all positively charged residues is analyzed. Comparison with the results presented by Park and Miller [(1992) Biochemistry (preceding paper in this issue)] shows that all functionally important positive residues are located on the beta-sheet side of the toxin. These results are different from those obtained by Auguste et al. [(1992) Biochemistry 31, 648-654] on scyllatoxin, which blocks a different type of K+ channel. This study shows, in fact, that functionally important positive residues are located on the helix side of the toxin. Thus, charybdotoxin and scyllatoxin, which present the same global fold, interact with two different classes of K+ channels by two different parts of the motif. | ||
==About this Structure== | ==About this Structure== | ||
2CRD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Leiurus_quinquestriatus_hebraeus Leiurus quinquestriatus hebraeus]. The following page contains interesting information on the relation of 2CRD with [[http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb38_1.html Potassium Channels]]. Full crystallographic information is available from [http:// | 2CRD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Leiurus_quinquestriatus_hebraeus Leiurus quinquestriatus hebraeus]. The following page contains interesting information on the relation of 2CRD with [[http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb38_1.html Potassium Channels]]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2CRD OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: neurotoxin]] | [[Category: neurotoxin]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:51:38 2008'' | ||
Revision as of 17:51, 21 February 2008
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ANALYSIS OF SIDE-CHAIN ORGANIZATION ON A REFINED MODEL OF CHARYBDOTOXIN: STRUCTURAL AND FUNCTIONAL IMPLICATIONS
OverviewOverview
The spatial organization of side chains on a refined model of charybdotoxin is presented. First, the structural role of two groups of well-defined, low-accessible side chains (Thr3, Val5, Val16, Leu20, Cys33 and Leu20, His21, Thr23, Cys17, Cys35) is discussed. These side chains are conserved in three out of the five known scorpion toxins acting on K+ channels. Interestingly, they are not conserved in scyllatoxin which presents a slightly different secondary structure organization. Second, the spatial organization of all positively charged residues is analyzed. Comparison with the results presented by Park and Miller [(1992) Biochemistry (preceding paper in this issue)] shows that all functionally important positive residues are located on the beta-sheet side of the toxin. These results are different from those obtained by Auguste et al. [(1992) Biochemistry 31, 648-654] on scyllatoxin, which blocks a different type of K+ channel. This study shows, in fact, that functionally important positive residues are located on the helix side of the toxin. Thus, charybdotoxin and scyllatoxin, which present the same global fold, interact with two different classes of K+ channels by two different parts of the motif.
About this StructureAbout this Structure
2CRD is a Single protein structure of sequence from Leiurus quinquestriatus hebraeus. The following page contains interesting information on the relation of 2CRD with [Potassium Channels]. Full crystallographic information is available from OCA.
ReferenceReference
Analysis of side-chain organization on a refined model of charybdotoxin: structural and functional implications., Bontems F, Gilquin B, Roumestand C, Menez A, Toma F, Biochemistry. 1992 Sep 1;31(34):7756-64. PMID:1380828
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