Structure and function of Bs164 β-mannosidase from Bacteroides salyersiae the founding member of glycoside hydrolase family GH164

Recent work exploring protein sequence space has revealed a new glycoside hydrolase (GH) family (GH164) of putative mannosidases. GH164 genes are present in several commensal bacteria, implicating these genes in the degradation of dietary glycans. However, little is known about the structure, mechanism of action, and substrate specificity of these enzymes. Herein we report the biochemical characterization and crystal structures of the founding member of this family (Bs164) from the human gut symbiont Bacteroides salyersiae. Previous reports of this enzyme indicated that it has α-mannosidase activity, however, we conclusively show that it cleaves only β-mannose linkages. Using NMR spectroscopy, detailed enzyme kinetics of WT and mutant Bs164, and multiangle light scattering we found that it is a trimeric retaining β-mannosidase, that is susceptible to several known mannosidase inhibitors. X-ray crystallography revealed the structure of Bs164, the first known structure of a GH164, at 1.91 Å resolution. Bs164 is composed of three domains: a (β/α)8 barrel, a trimerization domain, and a β-sandwich domain, representing a previously unobserved structural-fold for β-mannosidases. Structures of Bs164 at 1.80–2.55 Å resolution in complex with the inhibitors noeuromycin, mannoimidazole, or 2,4-dinitrophenol 2-deoxy-2-fluoro-mannoside reveal the residues essential for specificity and catalysis including the catalytic nucleophile (Glu-297) and acid/base residue (Glu-160). These findings further our knowledge of the mechanisms commensal microbes use for nutrient acquisition.

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Modeled 3D-Structures of Proteobacterial Transglycosylases from Glycoside Hydrolase Family 17 Give Insight in Ligand Interactions Explaining Differences in Transglycosylation Products

Applied Sciences ◽

10.3390/app11094048 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4048

Author(s):

Javier A. Linares-Pastén ◽

Lilja Björk Jonsdottir ◽

Gudmundur O. Hreggvidsson ◽

Olafur H. Fridjonsson ◽

Hildegard Watzlawick ◽

...

Keyword(s):

Glycoside Hydrolase ◽

Ligand Docking ◽

Glycoside Hydrolase Family ◽

Ligand Interactions ◽

Tim Barrel ◽

Branching Point ◽

The Difference ◽

Dynamics Simulations ◽

And Function ◽

Hydrolase Family

The structures of glycoside hydrolase family 17 (GH17) catalytic modules from modular proteins in the ndvB loci in Pseudomonas aeruginosa (Glt1), P. putida (Glt3) and Bradyrhizobium diazoefficiens (previously B. japonicum) (Glt20) were modeled to shed light on reported differences between these homologous transglycosylases concerning substrate size, preferred cleavage site (from reducing end (Glt20: DP2 product) or non-reducing end (Glt1, Glt3: DP4 products)), branching (Glt20) and linkage formed (1,3-linkage in Glt1, Glt3 and 1,6-linkage in Glt20). Hybrid models were built and stability of the resulting TIM-barrel structures was supported by molecular dynamics simulations. Catalytic amino acids were identified by superimposition of GH17 structures, and function was verified by mutagenesis using Glt20 as template (i.e., E120 and E209). Ligand docking revealed six putative subsites (−4, −3, −2, −1, +1 and +2), and the conserved interacting residues suggest substrate binding in the same orientation in all three transglycosylases, despite release of the donor oligosaccharide product from either the reducing (Glt20) or non-reducing end (Glt1, Gl3). Subsites +1 and +2 are most conserved and the difference in release is likely due to changes in loop structures, leading to loss of hydrogen bonds in Glt20. Substrate docking in Glt20 indicate that presence of covalently bound donor in glycone subsites −4 to −1 creates space to accommodate acceptor oligosaccharide in alternative subsites in the catalytic cleft, promoting a branching point and formation of a 1,6-linkage. The minimum donor size of DP5, can be explained assuming preferred binding of DP4 substrates in subsite −4 to −1, preventing catalysis.

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Endo-fucoidan hydrolases from glycoside hydrolase family 107 (GH107) display structural and mechanistic similarities to α-l-fucosidases from GH29

Journal of Biological Chemistry ◽

10.1074/jbc.ra118.005134 ◽

2018 ◽

Vol 293 (47) ◽

pp. 18296-18308 ◽

Cited By ~ 10

Author(s):

Chelsea Vickers ◽

Feng Liu ◽

Kento Abe ◽

Orly Salama-Alber ◽

Meredith Jenkins ◽

...

Keyword(s):

Glycoside Hydrolase ◽

Biological Activities ◽

Bacterial Species ◽

Structural Data ◽

Side Chain ◽

Glycoside Hydrolase Family ◽

X Ray Crystallography ◽

Catalytic Mechanisms ◽

Thickening Agents ◽

Hydrolase Family

Fucoidans are chemically complex and highly heterogeneous sulfated marine fucans from brown macro algae. Possessing a variety of physicochemical and biological activities, fucoidans are used as gelling and thickening agents in the food industry and have anticoagulant, antiviral, antitumor, antibacterial, and immune activities. Although fucoidan-depolymerizing enzymes have been identified, the molecular basis of their activity on these chemically complex polysaccharides remains largely uninvestigated. In this study, we focused on three glycoside hydrolase family 107 (GH107) enzymes: MfFcnA and two newly identified members, P5AFcnA and P19DFcnA, from a bacterial species of the genus Psychromonas. Using carbohydrate-PAGE, we show that P5AFcnA and P19DFcnA are active on fucoidans that differ from those depolymerized by MfFcnA, revealing differential substrate specificity within the GH107 family. Using a combination of X-ray crystallography and NMR analyses, we further show that GH107 family enzymes share features of their structures and catalytic mechanisms with GH29 α-l-fucosidases. However, we found that GH107 enzymes have the distinction of utilizing a histidine side chain as the proposed acid/base catalyst in its retaining mechanism. Further interpretation of the structural data indicated that the active-site architectures within this family are highly variable, likely reflecting the specificity of GH107 enzymes for different fucoidan substructures. Together, these findings begin to illuminate the molecular details underpinning the biological processing of fucoidans.

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Structure of a glycoside hydrolase family 50 enzyme from a subfamily that is enriched in human gut microbiome bacteroidetes

Proteins Structure Function and Bioinformatics ◽

10.1002/prot.25189 ◽

2016 ◽

Vol 85 (1) ◽

pp. 182-187 ◽

Cited By ~ 6

Author(s):

Kaleigh Giles ◽

Benjamin Pluvinage ◽

Alisdair B. Boraston

Keyword(s):

Gut Microbiome ◽

Glycoside Hydrolase ◽

Glycoside Hydrolase Family ◽

Human Gut ◽

Human Gut Microbiome ◽

Hydrolase Family

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Biochemical characterization of a glycoside hydrolase family 43 β-D-galactofuranosidase from the fungus Aspergillus niger

10.1101/2021.10.27.466152 ◽

2021 ◽

Author(s):

Gregory S Bulmer ◽

Fang Wei Yuen ◽

Naimah Begum ◽

Bethan S Jones ◽

Sabine S Flitsch ◽

...

Keyword(s):

Aspergillus Niger ◽

Glycoside Hydrolase ◽

Biochemical Characterization ◽

Maximum Activity ◽

Glycoside Hydrolase Family ◽

Enzyme Specificity ◽

Fungal Enzymes ◽

Glycoside Hydrolase Family 43 ◽

Hydrolase Family

β-D-Galactofuranose (Galf) and its polysaccharides are found in bacteria, fungi and protozoa but do not occur in mammalian tissues, and thus represent a specific target for anti-pathogenic drugs. Understanding the enzymatic degradation of these polysaccharides is therefore of great interest, but the identity of fungal enzymes with exclusively galactofuranosidase activity has so far remained elusive. Here we describe the identification and characterization of a galactofuranosidase from the industrially important fungus Aspergillus niger. Phylogenetic analysis of glycoside hydrolase family 43 subfamily 34 (GH43_34) members revealed the occurrence of three distinct clusters and, by comparison with specificities of characterized bacterial members, suggested a basis for prediction of enzyme specificity. Using this rationale, in tandem with molecular docking, we identified a putative β-D-galactofuranosidase from A. niger which was recombinantly expressed in Escherichia coli. The Galf-specific hydrolase, encoded by xynD demonstrates maximum activity at pH 5, 25 °C towards 4-Nitrophenyl-β-galactofuranoside (pNP-βGalf), with a Km of 17.9 ± 1.9 mM and Vmax of 70.6 ± 5.3 μmol min-1. The characterization of this first fungal GH43 galactofuranosidase offers further molecular insight into the degradation of Galf-containing structures and may inform clinical treatments against fungal pathogens.

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Kinetics of substrate transglycosylation by glycoside hydrolase family 3 glucan (1→3)-β-glucosidase from the white-rot fungus Phanerochaete chrysosporium

Carbohydrate Research ◽

10.1016/j.carres.2004.09.019 ◽

2004 ◽

Vol 339 (18) ◽

pp. 2851-2857 ◽

Cited By ~ 40

Author(s):

Rie Kawai ◽

Kiyohiko Igarashi ◽

Motomitsu Kitaoka ◽

Tadashi Ishii ◽

Masahiro Samejima

Keyword(s):

Phanerochaete Chrysosporium ◽

Glycoside Hydrolase ◽

White Rot ◽

White Rot Fungus ◽

Glycoside Hydrolase Family ◽

Kinetics Of ◽

Hydrolase Family

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Characterization of a novel multidomain CE15-GH8 enzyme encoded by a polysaccharide utilization locus in the human gut bacterium Bacteroides eggerthii

Scientific Reports ◽

10.1038/s41598-021-96659-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Cathleen Kmezik ◽

Daniel Krska ◽

Scott Mazurkewich ◽

Johan Larsbrink

Keyword(s):

Biochemical Characterization ◽

Glycoside Hydrolase Family ◽

Carbohydrate Active Enzymes ◽

Human Gut ◽

Glucuronoyl Esterase ◽

Cob Biomass ◽

Polysaccharide Utilization Loci ◽

Hydrolase Family ◽

Discrete Functions

AbstractBacteroidetes are efficient degraders of complex carbohydrates, much thanks to their use of polysaccharide utilization loci (PULs). An integral part of PULs are highly specialized carbohydrate-active enzymes, sometimes composed of multiple linked domains with discrete functions—multicatalytic enzymes. We present the biochemical characterization of a multicatalytic enzyme from a large PUL encoded by the gut bacterium Bacteroides eggerthii. The enzyme, BeCE15A-Rex8A, has a rare and novel architecture, with an N-terminal carbohydrate esterase family 15 (CE15) domain and a C-terminal glycoside hydrolase family 8 (GH8) domain. The CE15 domain was identified as a glucuronoyl esterase (GE), though with relatively poor activity on GE model substrates, attributed to key amino acid substitutions in the active site compared to previously studied GEs. The GH8 domain was shown to be a reducing-end xylose-releasing exo-oligoxylanase (Rex), based on having activity on xylooligosaccharides but not on longer xylan chains. The full-length BeCE15A-Rex8A enzyme and the Rex domain were capable of boosting the activity of a commercially available GH11 xylanase on corn cob biomass. Our research adds to the understanding of multicatalytic enzyme architectures and showcases the potential of discovering novel and atypical carbohydrate-active enzymes from mining PULs.

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Discovery of α-l-arabinopyranosidases from human gut microbiome expands the diversity within glycoside hydrolase family 42

Journal of Biological Chemistry ◽

10.1074/jbc.m117.792598 ◽

2017 ◽

Vol 292 (51) ◽

pp. 21092-21101 ◽

Cited By ~ 4

Author(s):

Alexander Holm Viborg ◽

Takane Katayama ◽

Takatoshi Arakawa ◽

Maher Abou Hachem ◽

Leila Lo Leggio ◽

...

Keyword(s):

Gut Microbiome ◽

Glycoside Hydrolase ◽

Glycoside Hydrolase Family ◽

Human Gut ◽

Human Gut Microbiome ◽

Hydrolase Family

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Engineering the Xylan Utilization System in Bacillus subtilis for Production of Acidic Xylooligosaccharides

Applied and Environmental Microbiology ◽

10.1128/aem.03246-13 ◽

2013 ◽

Vol 80 (3) ◽

pp. 917-927 ◽

Cited By ~ 23

Author(s):

Mun Su Rhee ◽

Lusha Wei ◽

Neha Sawhney ◽

John D. Rice ◽

Franz J. St. John ◽

...

Keyword(s):

Bacillus Subtilis ◽

Veterinary Medicine ◽

Glycoside Hydrolase ◽

Parent Strain ◽

Structure And Function ◽

Glycoside Hydrolase Family ◽

Content Type ◽

Potential Source ◽

And Function ◽

Hydrolase Family

ABSTRACTXylans are the predominant polysaccharides in hemicelluloses and an important potential source of biofuels and chemicals. The ability ofBacillus subtilissubsp.subtilisstrain 168 to utilize xylans has been ascribed to secreted glycoside hydrolase family 11 (GH11) and GH30 endoxylanases, encoded by thexynAandxynCgenes, respectively. Both of these enzymes have been defined with respect to structure and function. In this study, the effects of deletion of thexynAandxynCgenes, individually and in combination, were evaluated for xylan utilization and formation of acidic xylooligosaccharides. Parent strain 168 depolymerizes methylglucuronoxylans (MeGXn), releasing the xylobiose and xylotriose utilized for growth and accumulating the aldouronate methylglucuronoxylotriose (MeGX3) with some methylglucuronoxylotetraose (MeGX4). The combined GH11 and GH30 activities process the products generated by their respective actions on MeGXnto release a maximal amount of neutral xylooligosaccharides for assimilation and growth, at the same time forming MeGX3in which the internal xylose is substituted with methylglucuronate (MeG). Deletion ofxynAresults in the accumulation of β-1,4-xylooligosaccharides with degrees of polymerization ranging from 4 to 18 and an average degree of substitution of 1 in 7.2, each with a single MeG linked α-1,2 to the xylose penultimate to the xylose at the reducing terminus. Deletion of thexynCgene results in the accumulation of aldouronates comprised of 4 or more xylose residues in which the MeG may be linked α-1,2 to the xylose penultimate to the nonreducing xylose. TheseB. subtilislines may be used for the production of acidic xylooligosaccharides with applications in human and veterinary medicine.

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Structural and functional studies of the glycoside hydrolase family 3 β-glucosidase Cel3A from the moderately thermophilic fungusRasamsonia emersonii

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798316008482 ◽

2016 ◽

Vol 72 (7) ◽

pp. 860-870 ◽

Cited By ~ 16

Author(s):

Mikael Gudmundsson ◽

Henrik Hansson ◽

Saeid Karkehabadi ◽

Anna Larsson ◽

Ingeborg Stals ◽

...

Keyword(s):

Glycoside Hydrolase ◽

Biochemical Characterization ◽

Cellulosic Biomass ◽

Glycoside Hydrolase Family ◽

Hypocrea Jecorina ◽

Moderately Thermophilic ◽

Functional Studies ◽

Excellent Candidate ◽

Hydrolase Family

The filamentous fungusHypocrea jecorinaproduces a number of cellulases and hemicellulases that act in a concerted fashion on biomass and degrade it into monomeric or oligomeric sugars. β-Glucosidases are involved in the last step of the degradation of cellulosic biomass and hydrolyse the β-glycosidic linkage between two adjacent molecules in dimers and oligomers of glucose. In this study, it is shown that substituting the β-glucosidase fromH. jecorina(HjCel3A) with the β-glucosidase Cel3A from the thermophilic fungusRasamsonia emersonii(ReCel3A) in enzyme mixtures results in increased efficiency in the saccharification of lignocellulosic materials. Biochemical characterization ofReCel3A, heterologously produced inH. jecorina, reveals a preference for disaccharide substrates over longer gluco-oligosaccharides. Crystallographic studies ofReCel3A revealed a highly N-glycosylated three-domain dimeric protein, as has been observed previously for glycoside hydrolase family 3 β-glucosidases. The increased thermal stability and saccharification yield and the superior biochemical characteristics ofReCel3A compared withHjCel3A and mixtures containingHjCel3A makeReCel3A an excellent candidate for addition to enzyme mixtures designed to operate at higher temperatures.

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