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1i2v
From Proteopedia
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NMR SOLUTION STRUCTURES OF AN ANTIFUNGAL AND ANTIBACTERIAL MUTANT OF HELIOMICIN
Overview
In response to an experimental infection, the lepidopteran Heliothis, virescens produces an antifungal protein named heliomicin. Heliomicin, displays sequence similarities with antifungal plant defensins and, antibacterial or antifungal insect defensins. To gain information about, the structural elements required for either antifungal or antibacterial, activity, heliomicin and selected point-mutated variants were expressed in, yeast as fusion proteins. The effects of mutations, defined by comparing, the primary structure of heliomicin with the sequences of members of the, insect defensin family, were analyzed using antibacterial and antifungal, assays. One of the variants shows significant activity against, Gram-positive bacteria while remaining efficient against fungi. The, three-dimensional structures of this variant and of the wild-type protein, were determined by two-dimensional (1)H NMR to establish a correlation, between structure and antibacterial or antifungal activity. Wild-type and, mutated heliomicins adopt a similar scaffold, including the so-called, cysteine-stabilized alphabeta motif. A comparison of their structures with, other defensin-type molecules indicates that common hydrophobic, characteristics can be assigned to all the antifungal proteins. A, comparative analysis of various structural features of heliomicin mutant, and of antibacterial defensins enables common properties to be assessed, which will help to design new mutants with increased antibacterial, activity.
About this Structure
1I2V is a Single protein structure of sequence from Heliothis virescens. Full crystallographic information is available from OCA.
Reference
Solution structures of the antifungal heliomicin and a selected variant with both antibacterial and antifungal activities., Lamberty M, Caille A, Landon C, Tassin-Moindrot S, Hetru C, Bulet P, Vovelle F, Biochemistry. 2001 Oct 9;40(40):11995-2003. PMID:11580275
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