4q0v

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 9: Line 9:
<div style="background-color:#fffaf0;">
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
== Publication Abstract from PubMed ==
-
Acinetobacter sp. L-ribose isomerase (L-RI) catalyzes a reversible isomerization reaction between L-ribose and L-ribulose. To date, information on L-RI remains limited and its amino-acid sequence shows no similarity to those of any known enzymes. Here, recombinant His-tagged L-RI was successfully overexpressed, purified and crystallized. Crystals of His-tagged L-RI were obtained by the hanging-drop vapour-diffusion method at room temperature as two crystal forms which belonged to the monoclinic space group C2, with unit-cell parameters a = 96.60, b = 105.89, c = 71.83 A, beta = 118.16 degrees , and the orthorhombic space group F222, with unit-cell parameters a = 96.44, b = 106.26, c = 117.83 A. Diffraction data were collected to 3.1 and 2.2 A resolution, respectively.
+
l-Ribose, a pentose, is not known to exist in nature. Although organisms typically do not have a metabolic pathway that uses l-ribose as a carbon source, prokaryotes use various sugars as carbon sources for survival. Acinetobacter sp. DL-28 has been shown to express the novel enzyme, l-ribose isomerase (AcL-RbI), which catalyzes reversible isomerization between l-ribose and l-ribulose. AcL-RbI showed the highest activity to l-ribose, followed by d-lyxose with 47% activity, and had no significant amino acid sequence similarity to structure-known proteins, except for weak homology with the d-lyxose isomerases from Escherichia coli O157 : H7 (18%) and Bacillus subtilis strain (19%). Thus, AcL-RbI is expected to have the unique three-dimensional structure to recognize l-ribose as its ideal substrate. The X-ray structures of AcL-RbI in complexes with substrates were determined. AcL-RbI had a cupin-type beta-barrel structure, and the catalytic site was found between two large beta-sheets with a bound metal ion. The catalytic site structures clearly showed that AcL-RbI adopted a cis-enediol intermediate mechanism for the isomerization reaction using two glutamate residues (Glu113 and Glu204) as acid/base catalysts. In its crystal form, AcL-RbI formed a unique homotetramer with many substrate sub-binding sites, which likely facilitated capture of the substrate. DATABASE: The atomic coordinates and structure factors of AcL-RbI/l-ribose, AcL-RbI/l-ribulose, AcL-RbI/ribitol, E204Q/l-ribose and E204Q/l-ribulose have been deposited in the Protein Data Bank under accession codes, 4Q0P, 4Q0Q, 4Q0S, 4Q0U and 4Q0V. STRUCTURED DIGITAL ABSTRACT: * AcL-RbI and AcL-RbI bind by x-ray crystallography (View interaction).
-
Overexpression, crystallization and preliminary X-ray diffraction analysis of L-ribose isomerase from Acinetobacter sp. strain DL-28.,Yoshida H, Teraoka M, Yoshihara A, Izumori K, Kamitori S Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Oct 1;67(Pt 10):1281-4., doi: 10.1107/S1744309111030351. Epub 2011 Sep 30. PMID:22102048<ref>PMID:22102048</ref>
+
X-ray structure of a novel l-ribose isomerase acting on a non-natural sugar l-ribose as its ideal substrate.,Yoshida H, Yoshihara A, Teraoka M, Terami Y, Takata G, Izumori K, Kamitori S FEBS J. 2014 May 20. doi: 10.1111/febs.12850. PMID:24846739<ref>PMID:24846739</ref>
-
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
+
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
</div>
== References ==
== References ==

Revision as of 07:00, 11 June 2014

Crystal structure of Acinetobacter sp. DL28 L-ribose isomerase mutant E204Q in complex with L-ribulose

4q0v, resolution 1.98Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4q0v"
Views
Personal tools
Navigation
Toolbox