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Sandbox UNLPam 7

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== Crystal structure of a novel two domain GH78 family a-rhamnosidase from Klebsiella
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== Crystal structure of a novel two domain GH78 family a-rhamnosidase from Klebsiella oxytoca with rhamnose bound ==
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oxytoca with rhamnose bound ==
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<StructureSection load='1stp' size='340' side='right' caption='Caption for this structure' scene=''>
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== Structure ==
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The crystal structure of the GH78 family a-rhamnosidase from Klebsiella oxytoca (KoRha) has been determined at 2.7 A °
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resolution with rhamnose bound in the active site of the catalytic domain. Curiously, the putative catalytic acid, Asp 222, is
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preceded by an unusual non-proline cis-peptide bond which helps to project the carboxyl group into the active centre. This
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KoRha homodimeric structure is significantly smaller than those of the other previously determined GH78 structures.
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Nevertheless, the enzyme displays a-rhamnosidase activity when assayed in vitro, suggesting that the additional structural
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domains found in the related enzymes are dispensible for function.
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== Function ==
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==Introduction==
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a-L-rhamnose is found in plants and bacteria
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<StructureSection load='4xhc' size='350' side='right' caption='X-ray crystal structure of the a-L-rhamnosidase from K. oxytoca (KoRha).' scene='71/719552/4xhc_1/1'>4xhc structure</scene>'>
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a-L-rhamnosidases (E.C. 3.2.1.40) are found widely distributed
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in nature and have been reported in animals,
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plants, yeast, fungi and bacteria, where they are responsible
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for the cleavage of a-L-rhamnose from a wide range of
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compounds.1 a-L-rhamnose is found in plants and bacteria
as components of polysaccharides, such as pectins,2 and
as components of polysaccharides, such as pectins,2 and
the O antigen polysaccharides, responsible for determining
the O antigen polysaccharides, responsible for determining
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and for the release of flavonoids from rhamnosylated precursors;
and for the release of flavonoids from rhamnosylated precursors;
in wine production they play a role in the hydrolysis
in wine production they play a role in the hydrolysis
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of glycosylated terpene aroma compounds.5 In the
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of glycosylated terpene aroma compounds.
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context of expanding and diversifying the suite of enzymes
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available to us for carbohydrate biotransformations,6–13 we
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were drawn to consider a-rhamnosidases.
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In the CAZy database,14 rhamnosidases are currently
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classified into GH28 pectin hydrolases, GH78 containing
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exclusively rhamnosidases, and GH106 containing a single enzyme from Sphingomonas
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== Disease ==
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== Relevance ==
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== Structural highlights ==
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This is a sample scene created with SAT to <scene name="/12/3456/Sample/1">color</scene> by Group, and another to make <scene name="/12/3456/Sample/2">a transparent representation</scene> of the protein. You can make your own scenes on SAT starting from scratch or loading and editing one of these sample scenes.
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==KoRha structure==
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The crystal structure of KoRha with rhamnose bound was
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determined to 2.7A ° resolution. The final model consisted of
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two KoRha subunits related by a non-crystallographic twofold
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axis (giving a corresponding solvent content of 73%) in
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the asymmetric unit, with each monomer containing a
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bound rhamnose. Dynamic light scattering had suggested
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that KoRha was a homodimer in solution and the structure
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of KoRha confirmed this, giving a dimer interface of 1389.9
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A °
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2 (as calculated using the PISA server (http://www.ebi.ac.
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uk/pdbe/pisa/).
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Each monomer of KoRha is composed of two
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domains. Domain A, the catalytic domain, is mainly ahelical,
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consisting of residues 11–30 and 180–523, and
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contains the bound rhamnose. Domain B, the dimerization
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domain, is a b-sandwich domain consisting of residues
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31–179.
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<scene name='71/719552/4xhc_1/1'>4xhc structure</scene>
</StructureSection>
</StructureSection>
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== References ==
 
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<references/>
 

Current revision

Crystal structure of a novel two domain GH78 family a-rhamnosidase from Klebsiella oxytoca with rhamnose bound

Introduction

X-ray crystal structure of the a-L-rhamnosidase from K. oxytoca (KoRha).

Drag the structure with the mouse to rotate
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