1NAR

CRYSTAL STRUCTURE OF NARBONIN REFINED AT 1.8 ANGSTROMS RESOLUTION

Summary for 1NAR

• Entry DOI: 10.2210/pdb1nar/pdb
• Descriptor: NARBONIN (2 entities in total)
• Functional Keywords: plant seed protein
• Biological source: Vicia narbonensis
• Total number of polymer chains: 1
• Total formula weight: 33140.18

Authors

Hennig, M.,Schlesier, B.,Wilson, K.S. (deposition date: 1993-09-10, release date: 1994-01-31, Last modification date: 2024-02-14)

Primary citation

Hennig, M.,Pfeffer-Hennig, S.,Dauter, Z.,Wilson, K.S.,Schlesier, B.,Nong, V.H.
Crystal structure of narbonin at 1.8 A resolution.
Acta Crystallogr.,Sect.D, 51:177-189, 1995

PubMed Abstract: 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.

PubMed: 15299319
DOI: 10.1107/S0907444994009807

Experimental method

X-RAY DIFFRACTION (1.8 Å)