 |
PDBsum entry 4xut
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Sugar binding protein
|
PDB id
|
|
|
|
4xut
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Exploring multimodularity in plant cell wall deconstruction: structural and functional analysis of xyn10c containing the cbm22-1-Cbm22-2 tandem.
|
|
|
Authors
|
|
M.A.Sainz-Polo,
B.González,
M.Menéndez,
F.I.Pastor,
J.Sanz-Aparicio.
|
|
|
Ref.
|
|
J Biol Chem, 2015,
290,
17116-17130.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Elucidating the molecular mechanisms regulating multimodularity is a challenging
task. Paenibacillus barcinonensis Xyn10C is a 120-kDa modular enzyme that
presents the CBM22/GH10/CBM9 architecture found in a subset of large xylanases.
We report here the three-dimensional structure of the Xyn10C N-terminal region,
containing the xylan-binding CBM22-1-CBM22-2 tandem (Xyn10C-XBD), which
represents the first solved crystal structure of two contiguous CBM22 modules.
Xyn10C-XBD is folded into two separate CBM22 modules linked by a flexible
segment that endows the tandem with extraordinary plasticity. Each isolated
domain has been expressed and crystallized, and their binding abilities have
been investigated. Both domains contain the R(W/Y)YYE motif required for xylan
binding. However, crystallographic analysis of CBM22-2 complexes shows Trp-308
as an additional binding determinant. The long loop containing Trp-308 creates a
platform that possibly contributes to the recognition of precise decorations at
subsite S2. CBM22-2 may thus define a subset of xylan-binding CBM22 modules
directed to particular regions of the polysaccharide. Affinity electrophoresis
reveals that Xyn10C-XBD binds arabinoxylans more tightly, which is more apparent
when CBM22-2 is tested against highly substituted xylan. The crystal structure
of the catalytic domain, also reported, shows the capacity of the active site to
accommodate xylan substitutions at almost all subsites. The structural
differences found at both Xyn10C-XBD domains are consistent with the isothermal
titration calorimetry experiments showing two sites with different affinities in
the tandem. On the basis of the distinct characteristics of CBM22, a delivery
strategy of Xyn10C mediated by Xyn10C-XBD is proposed.
|
|
|
Secondary reference #1
|
|
|
Title
|
|
Crystallization and preliminary X-Ray diffraction analysis of the n-Terminal domain of paenibacillus barcinonensis xylanase 10c containing the cbm22-1-Cbm22-2 tandem.
|
|
|
Authors
|
|
M...Sainz-Polo,
B.González,
F.I.Pastor,
J.Sanz-Aparicio.
|
|
|
Ref.
|
|
Acta Crystallogr F Struct Biol Commun, 2015,
71,
136-140.
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
