1nar
From Proteopedia
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CRYSTAL STRUCTURE OF NARBONIN REFINED AT 1.8 ANGSTROMS RESOLUTION
Overview
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 Structure
1NAR is a Single protein structure of sequence from Vicia narbonensis. Full crystallographic information is available from OCA.
Reference
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 Sat Nov 24 22:51:19 2007
