Biochemical and Structural Characterization of a Five-domain GH115-Glucuronidase from the Marine Bacterium Saccharophagus degradans 2-40(T)
Artikel i vetenskaplig tidskrift, 2016

Glucuronic acid (GlcAp) and/or methylglucuronic acid (MeGlcAp) decorate the major forms of xylan in hardwood and coniferous softwoods as well as many cereal grains. Accordingly, the complete utilization of glucuronoxylans or conversion to sugar precursors requires the action of main chain xylanases as well as -glucuronidases that release the - (12)-linked (Me)GlcAp side groups. Herein, a family GH115 enzymefrom the marine bacterium Saccharophagus degradans 2-40(T), SdeAgu115A, demonstrated activity toward glucuronoxylan and oligomers thereof with preference toward MeGlcAp linked to internal xylopyranosyl residues. Unique biochemical characteristics of NaCl activation were also observed. The crystal structure of SdeAgu115A revealed a five-domain architecture, with an additional insertion C+ domain that had significant impact on the domain arrangement of SdeAgu115A monomer and its dimerization. The participation of domain C+ in substrate binding was supported by reduced substrate inhibition upon introducing W773A, W689A, and F696A substitutions within this domain. In addition to Asp-335, the catalytic essentiality of Glu-216 was revealed by site-specific mutagenesis. A primary sequence analysis suggested that the SdeAgu115A architecture is shared by more than half of GH115 members, thus defining a distinct archetype for GH115 enzymes.

Biochemistry & Molecular Biology

protein domain

plant-cell wall

modification

crystal structure

crystal-structures

enzyme structure

inverting character

enzyme catalysis

thermotoga-maritima msb8

xylan

schizophyllum-commune

catalytic apparatus

density

analytical biochemistry

GH115-glucuronidase

enzyme domain composition

ruiter ga

family gh115

carbohydrate

carbohydrate degradation

1992

polysaccharides

v207

alpha-glucuronidase

p176

Författare

W. J. Wang

Unknown organization

R. Y. Yan

Unknown organization

B. P. Nocek

Unknown organization

T. V. Vuong

Unknown organization

R. Di Leo

Unknown organization

X. H. Xu

Unknown organization

H. Cui

Unknown organization

Paul Gatenholm

Wallenberg Wood Science Center (WWSC)

Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Guillermo Toriz Gonzalez

Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

M. Tenkanen

Unknown organization

A. Savchenko

Unknown organization

E. R. Master

Unknown organization

Journal of Biological Chemistry

0021-9258 (ISSN) 1083-351X (eISSN)

Vol. 291 14120-14133

Ämneskategorier

Biokemi och molekylärbiologi

DOI

10.1074/jbc.M115.702944

PubMed

27129264