Understanding enzyme-substrate interactions in Carbohydrate Esterase Family 15
Poster (konferens), 2019

Carbohydrate Esterase Family 15 (CE15) is a rather small family, comprising approximately 200 members, which was established in CAZy (www.cazy.org) in 2006. The family was created following the characterization of a glucuronoyl esterase (GE) from the fungus Schizophyllum commune [1], which was shown to cleave methyl moieties ester-linked to the O6 position of glucuronic acid. CE15 enzymes are proposed to cleave ester linkages between lignin and glucuronoxylan, so-called lignin-carbohydrate complexes (LCCs), which are important features in biomass recalcitrance. We recently characterized ten new GEs from three bacterial species and solved the structures of two of these, essentially doubling both the biochemical and structural data available for the family [2].

An in-depth understanding of how CE15 enzymes interact with their complex substrates is still lacking, as only one structure with a monosaccharide ligand has been solved to date [3]. To address this, we have pursued solving new GE structures and obtaining protein-ligand complex structures. The studies have resulted in a novel structure exhibiting features with prominent inserts surrounding the active site, suggesting different specificities between bacterial and fungal GEs. In addition, we have solved the first structures of a CE15 enzyme with larger ligands, which gives direct evidence of how these enzymes interact with the different parts of its proposed physiological LCC substrates. Combined with kinetic characterizations, these new investigations greatly add to the knowledge of enzyme-substrate interactions in CE15 and enhances how these enzymes may act in natural conditions, which could aid in industrial biomass conversion.

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[1]  Španiková S.; Biely P. FEBS Lett. 2006, 580, 4597-4601.
[2]  Arnling Bååth J.; Mazurkewich S.; Knudsen R.M.; Poulsen J.N.; Olsson L.; Lo Leggio L.; Larsbrink J. Biotechnol Biofuels. 2018, 11, 213-226.
[3]  Charavgi M.D.; Dimarogona M.; Topakas E.; Christakopoulos P.; Chrysina E.D. Acta Crystallogr. D Biol. Crystallogr. 2013, 69, 63-73.

glucuronoxylan

crystallography

structural biology

lignin-carbohydrate complexes

CE15

biochemistry

glucuronoyl esterase

Författare

Scott Mazurkewich

Chalmers, Biologi och bioteknik, Industriell bioteknik

Jenny Arnling Bååth

Chalmers, Biologi och bioteknik, Industriell bioteknik

Jens-Christian N Poulsen

Köpenhamns universitet

Lisbeth Olsson

Chalmers, Biologi och bioteknik, Industriell bioteknik

Leila Lo Leggio

Köpenhamns universitet

Johan Larsbrink

Chalmers, Biologi och bioteknik, Industriell bioteknik

13th Biennial Carbohydrate Bioengineering Meeting
Toulouse, France,

Structure-based engineering of glucuronoyl esterases for separation of lignin and carbohydrates

Novo Nordisk Fonden, 2018-01-01 -- 2020-12-31.

Ämneskategorier

Biokemi och molekylärbiologi

Strukturbiologi

Biokatalys och enzymteknik

Fundament

Grundläggande vetenskaper

Styrkeområden

Livsvetenskaper och teknik (2010-2018)

Mer information

Senast uppdaterat

2019-06-19