1nar
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| , resolution 1.8Å | |||||||
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| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF NARBONIN REFINED AT 1.8 ANGSTROMS RESOLUTION
OverviewOverview
The three-dimensional structure of narbonin, a seed protein from Vicia narbonensis L, has been determined at 1.8 A resolution. Phase information was obtained by multiple isomorphous replacement and optimized anomalous dispersion. The narbonin structure was initially traced with only 17% amino-acid sequence information and preliminarily refined to a crystallographic R-factor of 16.5%. It is now refined to 15.9% using full sequence information derived from cDNA and after the addition of more solvent molecules. The monomeric molecule of narbonin is an eight-stranded parallel beta-barrel surrounded by alpha-helices in a beta/alpha-topology similar to that first observed in triose phosphate isomerase. Differences exist in the N-terminal part of the polypeptide chain, where the first helix is replaced by a loop and the second beta-strand is followed by an additional antiparallel alpha-sheet placed parallel on top of alpha-helices alpha3 and alpha4. Two short additional secondary structures are present. The first, an alpha-helix, is situated between the seventh beta-strand and the following helix, and the second, which is a 3(10) helix, between the eighth strand and the C-terminal helix. The most striking observation is the lack of a known enzymatic function for narbonin, because all TIM-like structures known so far are enzymes.
About this StructureAbout this Structure
1NAR is a Single protein structure of sequence from Vicia narbonensis. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of narbonin at 1.8 A resolution., Hennig M, Pfeffer-Hennig S, Dauter Z, Wilson KS, Schlesier B, Nong VH, Acta Crystallogr D Biol Crystallogr. 1995 Mar 1;51(Pt 2):177-89. PMID:15299319
Page seeded by OCA on Thu Mar 20 12:54:23 2008