1zrv
From Proteopedia
(New page: 200px<br /><applet load="1zrv" size="450" color="white" frame="true" align="right" spinBox="true" caption="1zrv" /> '''solution structure of spinigerin in H20/TFE ...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1zrv.gif|left|200px]]<br /><applet load="1zrv" size=" | + | [[Image:1zrv.gif|left|200px]]<br /><applet load="1zrv" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1zrv" /> | caption="1zrv" /> | ||
'''solution structure of spinigerin in H20/TFE 50%'''<br /> | '''solution structure of spinigerin in H20/TFE 50%'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Stomoxyn and spinigerin belong to the class of linear cysteine-free insect | + | Stomoxyn and spinigerin belong to the class of linear cysteine-free insect antimicrobial peptides that kill a range of microorganisms, parasites, and some viruses but without any lytic activity against mammalian erythrocytes. Stomoxyn is localized in the gut epithelium of the nonvector stable fly that is sympatric with the trypanosome vector tsetse fly. Spinigerin is stored and secreted by hemocytes from the fungus-growing termite. The structure of synthetic stomoxyn and spinigerin in aqueous solution and in TFE/water mixtures was analyzed by CD and NMR spectroscopy combined with molecular modeling calculations. Stomoxyn and spinigerin adopt a flexible random coil structure in water while both assume a stable helical structure in the presence of TFE. In 50% TFE, the structure of stomoxyn is typical of cecropins, including an amphipathic helix at the N-terminus and a hydrophobic C-terminus with helical features that probably fold in a helical conformation at higher TFE concentration. In contrast to stomoxyn, spinigerin acquires very rapidly a helical conformation. In 10% TFE the helix is highly bent and the structure is poorly defined. In 50% TFE, the helical structure is well defined all along its sequence, and the slightly bent alpha-helix displays an amphiphilic character, as observed for magainin 2. The structural similarities between stomoxyn and cecropin A from Hyalophora cecropia and between spinigerin and magainin 2 suggest a similar mode of action on the bacterial membranes of both pairs of peptides. Our results also confirm that TFE induces helix formation and propagation for amino acids showing helical propensity in water but also enhances the helix propagation propensity of nonpolar beta-branched residues. |
==About this Structure== | ==About this Structure== | ||
| - | 1ZRV is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http:// | + | 1ZRV is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ZRV OCA]. |
==Reference== | ==Reference== | ||
| Line 19: | Line 19: | ||
[[Category: helical peptide in tfe]] | [[Category: helical peptide in tfe]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:18:29 2008'' |
Revision as of 14:18, 21 February 2008
|
solution structure of spinigerin in H20/TFE 50%
Overview
Stomoxyn and spinigerin belong to the class of linear cysteine-free insect antimicrobial peptides that kill a range of microorganisms, parasites, and some viruses but without any lytic activity against mammalian erythrocytes. Stomoxyn is localized in the gut epithelium of the nonvector stable fly that is sympatric with the trypanosome vector tsetse fly. Spinigerin is stored and secreted by hemocytes from the fungus-growing termite. The structure of synthetic stomoxyn and spinigerin in aqueous solution and in TFE/water mixtures was analyzed by CD and NMR spectroscopy combined with molecular modeling calculations. Stomoxyn and spinigerin adopt a flexible random coil structure in water while both assume a stable helical structure in the presence of TFE. In 50% TFE, the structure of stomoxyn is typical of cecropins, including an amphipathic helix at the N-terminus and a hydrophobic C-terminus with helical features that probably fold in a helical conformation at higher TFE concentration. In contrast to stomoxyn, spinigerin acquires very rapidly a helical conformation. In 10% TFE the helix is highly bent and the structure is poorly defined. In 50% TFE, the helical structure is well defined all along its sequence, and the slightly bent alpha-helix displays an amphiphilic character, as observed for magainin 2. The structural similarities between stomoxyn and cecropin A from Hyalophora cecropia and between spinigerin and magainin 2 suggest a similar mode of action on the bacterial membranes of both pairs of peptides. Our results also confirm that TFE induces helix formation and propagation for amino acids showing helical propensity in water but also enhances the helix propagation propensity of nonpolar beta-branched residues.
About this Structure
1ZRV is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.
Reference
Solution structures of stomoxyn and spinigerin, two insect antimicrobial peptides with an alpha-helical conformation., Landon C, Meudal H, Boulanger N, Bulet P, Vovelle F, Biopolymers. 2006 Feb 5;81(2):92-103. PMID:16170803
Page seeded by OCA on Thu Feb 21 16:18:29 2008
