Activation and detoxification of cassava cyanogenic glucosides by the whitefly Bemisia tabaci

AbstractTwo-component plant defenses such as cyanogenic glucosides are produced by many plant species, but phloem-feeding herbivores have long been thought not to activate these defenses due to their mode of feeding, which causes only minimal tissue damage. Here, however, we report that cyanogenic glycoside defenses from cassava (Manihot esculenta), a major staple crop in Africa, are activated during feeding by a pest insect, the whitefly Bemisia tabaci, and the resulting hydrogen cyanide is detoxified by conversion to beta-cyanoalanine. Additionally, B. tabaci was found to utilize two metabolic mechanisms to detoxify cyanogenic glucosides by conversion to non-activatable derivatives. First, the cyanogenic glycoside linamarin was glucosylated 1–4 times in succession in a reaction catalyzed by two B. tabaci glycoside hydrolase family 13 enzymes in vitro utilizing sucrose as a co-substrate. Second, both linamarin and the glucosylated linamarin derivatives were phosphorylated. Both phosphorylation and glucosidation of linamarin render this plant pro-toxin inert to the activating plant enzyme linamarase, and thus these metabolic transformations can be considered pre-emptive detoxification strategies to avoid cyanogenesis.

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Analysis of the diversity of the glycoside hydrolase family 130 in mammal gut microbiomes reveals a novel mannoside-phosphorylase function

Microbial Genomics ◽

10.1099/mgen.0.000404 ◽

2020 ◽

Vol 6 (10) ◽

Author(s):

Ao Li ◽

Elisabeth Laville ◽

Laurence Tarquis ◽

Vincent Lombard ◽

David Ropartz ◽

...

Keyword(s):

Glycoside Hydrolase ◽

Sequence Similarity ◽

Gut Bacteria ◽

Glycoside Hydrolase Family ◽

Sequence Alignments ◽

Multiple Sequence ◽

Content Type ◽

Multiple Sequence Alignments ◽

Hydrolase Family

Mannoside phosphorylases are involved in the intracellular metabolization of mannooligosaccharides, and are also useful enzymes for the in vitro synthesis of oligosaccharides. They are found in glycoside hydrolase family GH130. Here we report on an analysis of 6308 GH130 sequences, including 4714 from the human, bovine, porcine and murine microbiomes. Using sequence similarity networks, we divided the diversity of sequences into 15 mostly isofunctional meta-nodes; of these, 9 contained no experimentally characterized member. By examining the multiple sequence alignments in each meta-node, we predicted the determinants of the phosphorolytic mechanism and linkage specificity. We thus hypothesized that eight uncharacterized meta-nodes would be phosphorylases. These sequences are characterized by the absence of signal peptides and of the catalytic base. Those sequences with the conserved E/K, E/R and Y/R pairs of residues involved in substrate binding would target β-1,2-, β-1,3- and β-1,4-linked mannosyl residues, respectively. These predictions were tested by characterizing members of three of the uncharacterized meta-nodes from gut bacteria. We discovered the first known β-1,4-mannosyl-glucuronic acid phosphorylase, which targets a motif of the Shigella lipopolysaccharide O-antigen. This work uncovers a reliable strategy for the discovery of novel mannoside-phosphorylases, reveals possible interactions between gut bacteria, and identifies a biotechnological tool for the synthesis of antigenic oligosaccharides.

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In vitro and in vivo characterization of three Cellvibrio japonicus glycoside hydrolase family 5 members reveals potent xyloglucan backbone-cleaving functions

Biotechnology for Biofuels ◽

10.1186/s13068-018-1039-6 ◽

2018 ◽

Vol 11 (1) ◽

Cited By ~ 11

Author(s):

Mohamed A. Attia ◽

Cassandra E. Nelson ◽

Wendy A. Offen ◽

Namrata Jain ◽

Gideon J. Davies ◽

...

Keyword(s):

Glycoside Hydrolase ◽

Glycoside Hydrolase Family ◽

Cellvibrio Japonicus ◽

In Vivo Characterization ◽

Hydrolase Family

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The BRANCHING ENZYME1 gene, encoding a glycoside hydrolase family 13 protein, is required for in vitro plant regeneration in Arabidopsis

Plant Cell Tissue and Organ Culture (PCTOC) ◽

10.1007/s11240-014-0439-y ◽

2014 ◽

Vol 117 (2) ◽

pp. 279-291 ◽

Cited By ~ 5

Author(s):

Xingchun Wang ◽

Zhirong Yang ◽

Min Wang ◽

Lingzhi Meng ◽

Yiwei Jiang ◽

...

Keyword(s):

Plant Regeneration ◽

Glycoside Hydrolase ◽

Glycoside Hydrolase Family ◽

In Vitro Plant Regeneration ◽

Gene Encoding ◽

In Vitro Plant ◽

Hydrolase Family ◽

Glycoside Hydrolase Family 13

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Identification of a Sulfatase that Detoxifies Glucosinolates in the Phloem-Feeding Insect Bemisia tabaci and Prefers Indolic Glucosinolates

Frontiers in Plant Science ◽

10.3389/fpls.2021.671286 ◽

2021 ◽

Vol 12 ◽

Author(s):

Abinaya Manivannan ◽

Bhawana Israni ◽

Katrin Luck ◽

Monika Götz ◽

Elena Seibel ◽

...

Keyword(s):

Bemisia Tabaci ◽

Plant Colonization ◽

Generalist Herbivore ◽

Indolic Glucosinolates ◽

Cruciferous Plants ◽

Phloem Feeding ◽

Globally Distributed ◽

Sulfur Containing

Cruciferous plants in the order Brassicales defend themselves from herbivory using glucosinolates: sulfur-containing pro-toxic metabolites that are activated by hydrolysis to form compounds, such as isothiocyanates, which are toxic to insects and other organisms. Some herbivores are known to circumvent glucosinolate activation with glucosinolate sulfatases (GSSs), enzymes that convert glucosinolates into inactive desulfoglucosinolates. This strategy is a major glucosinolate detoxification pathway in a phloem-feeding insect, the silverleaf whitefly Bemisia tabaci, a serious agricultural pest of cruciferous vegetables. In this study, we identified and characterized an enzyme responsible for glucosinolate desulfation in the globally distributed B. tabaci species MEAM1. In in vitro assays, this sulfatase showed a clear preference for indolic glucosinolates compared with aliphatic glucosinolates, consistent with the greater representation of desulfated indolic glucosinolates in honeydew. B. tabaci might use this detoxification strategy specifically against indolic glucosinolates since plants may preferentially deploy indolic glucosinolates against phloem-feeding insects. In vivo silencing of the expression of the B. tabaci GSS gene via RNA interference led to lower levels of desulfoglucosinolates in honeydew. Our findings expand the knowledge on the biochemistry of glucosinolate detoxification in phloem-feeding insects and suggest how detoxification pathways might facilitate plant colonization in a generalist herbivore.

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Xylanases of glycoside hydrolase family 30 – An overview

Biotechnology Advances ◽

10.1016/j.biotechadv.2021.107704 ◽

2021 ◽

Vol 47 ◽

pp. 107704

Author(s):

Vladimír Puchart ◽

Katarína Šuchová ◽

Peter Biely

Keyword(s):

Glycoside Hydrolase ◽

Glycoside Hydrolase Family ◽

Hydrolase Family ◽

Glycoside Hydrolase Family 30

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Cyanogenic glycoside amygdalin influences functions of human osteoblasts in vitro

Journal of Environmental Science and Health Part B ◽

10.1080/03601234.2020.1852054 ◽

2021 ◽

Vol 56 (2) ◽

pp. 109-116

Author(s):

Radoslav Omelka ◽

Veronika Kovacova ◽

Vladimira Mondockova ◽

Birgit Grosskopf ◽

Adriana Kolesarova ◽

...

Keyword(s):

Cyanogenic Glycoside ◽

Human Osteoblasts

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1455. Potential Mechanisms of Cefiderocol MIC Increase in Enterobacterales in In Vitro Resistance Acquisition Studies

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1636 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S730-S730

Author(s):

Yoshinori Yamano ◽

Rio Nakamura ◽

Miki Takemura ◽

Roger Echols

Keyword(s):

Iron Transport ◽

Resistance Mechanisms ◽

Altered Expression ◽

Carbapenem Resistant ◽

Mueller Hinton ◽

Two Component ◽

Mueller Hinton Agar ◽

Related Proteins

Abstract Background Cefiderocol (CFDC) is a novel siderophore, iron-chelating cephalosporin, which is transported into bacteria via iron transporters. CFDC has potent in vitro and in vivo activity against all aerobic Gram-negative bacteria, including carbapenem-resistant strains. To date, clinical isolates with cefiderocol MIC >4 µg/mL have been found infrequently, in which the presence of a few β-lactamases or altered iron transport was found. We investigated potential new mechanisms causing CFDC MIC increases in non-clinical studies. Methods The mutation positions were determined by whole genome sequencing using four K. pneumoniae mutants including two KPC producers and one NDM producer that had shown CFDC MIC increases in previous in vitro resistance-acquisition studies. The mutant strains were obtained at the frequency of 10-7 to < 10-8 by spreading bacteria on standard Mueller‒Hinton agar medium containing CFDC at concentrations of 10× MIC, with or without apo-transferrin (20 μg/mL). CFDC MIC was determined by broth microdilution using iron-depleted cation-adjusted Mueller-Hinton broth based on Clinical and Laboratory Standards Institute guidelines. The emergence of MIC increase mutants was also assessed by in vitro chemostat models under humanized plasma pharmacokinetic exposures of CFDC. Results The possible resistance mechanisms were investigated. Mutation of baeS or envZ, sensors of two-component regulation systems, were found in three or two mutants among the tested four isolates, respectively, and caused the MIC to increase by 4–32-fold. The altered expression level of specific genes by the baeS or envZ mutation could affect CFDC susceptibility, but the specific genes have not been identified. In addition, the mutation of exbD, an accessory protein related to iron transport, was identified in one case and caused the MIC to increase by >8-fold. In vitro chemostat studies using two isolates (one NDM producer and one KPC producer) showed no resistance acquisition during 24-hour exposure. Table. Overview of mutation emergence in five isolates of K. pneumoniae Conclusion The mutation of two-component regulation systems (BaeSR and OmpR/EnvZ) and iron transport-related proteins were shown to be possible mechanisms causing CFDC MIC increases, but these mutants did not appear under human exposures. Disclosures Yoshinori Yamano, PhD, Shionogi & Co., Ltd. (Employee) Rio Nakamura, BSc, Shionogi & Co., Ltd. (Employee) Miki Takemura, MSc, Shionogi & Co., Ltd. (Employee) Roger Echols, MD, Shionogi Inc. (Consultant)

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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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The thermostable 4,6-α-glucanotransferase of Bacillus coagulans DSM 1 synthesizes isomaltooligosaccharides

Amylase ◽

10.1515/amylase-2021-0002 ◽

2021 ◽

Vol 5 (1) ◽

pp. 13-22

Author(s):

Gang Xiang ◽

Piet L. Buwalda ◽

Marc J.E.C van der Maarel ◽

Hans Leemhuis

Keyword(s):

Bacillus Coagulans ◽

Glycoside Hydrolase Family ◽

Rat Intestine ◽

Glycaemic Response ◽

Food Ingredient ◽

Starch Conversion ◽

Identification And Characterization ◽

Hydrolase Family

Abstract The 4,6-α-glucanotransferases of the glycoside hydrolase family 70 can convert starch into isomaltooligosaccharides (IMOs). However, no thermostable 4,6-α-glucanotransferases have been reported to date, limiting their applicability in the starch conversion industry. Here we report the identification and characterization of a thermostable 4,6-α-glucanotransferase from Bacillus coagulans DSM 1. The gene was cloned and the recombinant protein, called BcGtfC, was produced in Escherichia coli. BcGtfC is stable up to 66 °C in the presence of substrate. It converts debranched starch into an IMO product with a high percentage of α-1,6-glycosidic linkages and a relatively high molecular weight compared to commercially available IMOs. Importantly, the product is only partly and very slowly digested by rat intestine powder, suggesting that the IMO will provide a low glycaemic response in vivo when applied as food ingredient. Thus, BcGtfC is a thermostable 4,6-α-glucanotransferase suitable for the industrial production of slowly digestible IMOs from starch.

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