1cnv

</td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1cnv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cnv OCA], [https://pdbe.org/1cnv PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1cnv RCSB], [https://www.ebi.ac.uk/pdbsum/1cnv PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1cnv ProSAT]</span></td></tr>

[[https://www.uniprot.org/uniprot/CONB_CANEN CONB_CANEN]] May act as a carbohydrate-binding protein.

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== Publication Abstract from PubMed ==

Seeds of Canavalia ensiformis (jack bean) contain besides large amounts of canavalin and concanavalin A, a protein with a molecular mass of 33,800 which has been named concanavalin B. Although concanavalin B shares about 40% sequence identity with plant chitinases belonging to glycosyl hydrolase family 18, no chitinase activity could be detected for this protein. To resolve this incongruity concanavalin B was crystallised and its three-dimensional structure determined at 1.65 A (1 A = 0.1 nm) resolution. The structure consists of a single domain with a (beta/alpha)8 topology. A 30 amino acid residue long loop occurs between the second beta-strand of the barrel and the second alpha-helix. This extended loop is unusual for the (beta/alpha)8 topology, but appears in a similar conformation in the structures of the seed protein narbonin and several chitinases as well. Two non-proline cis-peptide bonds are present in the structure of concanavalin B: Ser34-Phe, and Trp265-Asn. This structural feature is rarely observed in proteins, but could also be identified in the three-dimensional structures of family 18 chitinases and narbonin in coincident positions. In the chitinases the aromatic residues of the non-proline cis-peptides have been proposed to have a function in the binding of the substrate. The region in concanavalin B, where in chitinases the active site is located, shows two significant differences. First, the catalytic glutamic acid is a glutamine in concanavalin B. Second, although part of the substrate binding cleft of the chitinases is present in concanavalin B, it is much shorter. From this we conclude that concanavalin B and family 18 chitinases are closely related, but that concanavalin B has lost its enzymatic function. It still may act as a carbohydrate binding protein, however.

Crystal structure of concanavalin B at 1.65 A resolution. An "inactivated" chitinase from seeds of Canavalia ensiformis.,Hennig M, Jansonius JN, Terwisscha van Scheltinga AC, Dijkstra BW, Schlesier B J Mol Biol. 1995 Nov 24;254(2):237-46. PMID:7490746<ref>PMID:7490746</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Hennig, M]]

[[Category: Seed protein]]