1gxo
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Enzyme-catalyzed beta-elimination of sugar uronic acids, exemplified by | + | Enzyme-catalyzed beta-elimination of sugar uronic acids, exemplified by the degradation of plant cell wall pectins, plays an important role in a wide spectrum of biological processes ranging from the recycling of plant biomass through to pathogen virulence. The three-dimensional crystal structure of the catalytic module of a "family PL-10" polysaccharide lyase, Pel10Acm from Cellvibrio japonicus, solved at a resolution of 1.3 A, reveals a new polysaccharide lyase fold and is the first example of a polygalacturonic acid lyase that does not exhibit the "parallel beta-helix" topology. The "Michaelis" complex of an inactive mutant in association with the substrate trigalacturonate/Ca2+ reveals the catalytic machinery harnessed by this polygalacturonate lyase, which displays a stunning resemblance, presumably through convergent evolution, to the tetragalacturonic acid complex observed for a structurally unrelated polygalacturonate lyase from family PL-1. Common coordination of the -1 and +1 subsite saccharide carboxylate groups by a protein-liganded Ca2+ ion, the positioning of an arginine catalytic base in close proximity to the alpha-carbon hydrogen and numerous other conserved enzyme-substrate interactions, considered in light of mutagenesis data for both families, suggest a generic polysaccharide anti-beta-elimination mechanism. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Pectate lyase]] | [[Category: Pectate lyase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Black, G | + | [[Category: Black, G W.]] |
| - | [[Category: Brown, I | + | [[Category: Brown, I E.]] |
| - | [[Category: Charnock, S | + | [[Category: Charnock, S J.]] |
| - | [[Category: Davies, G | + | [[Category: Davies, G J.]] |
| - | [[Category: Turkenburg, J | + | [[Category: Turkenburg, J P.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: elimination]] | [[Category: elimination]] | ||
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[[Category: pectate]] | [[Category: pectate]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:55:08 2008'' |
Revision as of 10:55, 21 February 2008
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MUTANT D189A OF FAMILY 10 POLYSACCHARIDE LYASE FROM CELLVIBRIO CELLULOSA IN COMPLEX WITH TRIGALATURONIC ACID
Overview
Enzyme-catalyzed beta-elimination of sugar uronic acids, exemplified by the degradation of plant cell wall pectins, plays an important role in a wide spectrum of biological processes ranging from the recycling of plant biomass through to pathogen virulence. The three-dimensional crystal structure of the catalytic module of a "family PL-10" polysaccharide lyase, Pel10Acm from Cellvibrio japonicus, solved at a resolution of 1.3 A, reveals a new polysaccharide lyase fold and is the first example of a polygalacturonic acid lyase that does not exhibit the "parallel beta-helix" topology. The "Michaelis" complex of an inactive mutant in association with the substrate trigalacturonate/Ca2+ reveals the catalytic machinery harnessed by this polygalacturonate lyase, which displays a stunning resemblance, presumably through convergent evolution, to the tetragalacturonic acid complex observed for a structurally unrelated polygalacturonate lyase from family PL-1. Common coordination of the -1 and +1 subsite saccharide carboxylate groups by a protein-liganded Ca2+ ion, the positioning of an arginine catalytic base in close proximity to the alpha-carbon hydrogen and numerous other conserved enzyme-substrate interactions, considered in light of mutagenesis data for both families, suggest a generic polysaccharide anti-beta-elimination mechanism.
About this Structure
1GXO is a Single protein structure of sequence from Cellvibrio japonicus with as ligand. Active as Pectate lyase, with EC number 4.2.2.2 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Convergent evolution sheds light on the anti-beta -elimination mechanism common to family 1 and 10 polysaccharide lyases., Charnock SJ, Brown IE, Turkenburg JP, Black GW, Davies GJ, Proc Natl Acad Sci U S A. 2002 Sep 17;99(19):12067-72. Epub 2002 Sep 9. PMID:12221284
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