Thermal Stability of Anisoyl Kaempferol Glycosides in Jack Bean ( Canavalia ensiformis (L.) DC) and Their Effect on α-Glucosidase Inhibition

Kaempferol glycosides are functional components of jack bean. The chemical stability of kaempferol glycosides under simulated food processing conditions was evaluated in this study by subjecting the methanol extract and each compound to heat treatment. During the heat treatment, rearrangement of the anisoyl group on the rhamnose moiety of the kaempferol glycoside was observed, followed by hydrolysis upon long-term heat treatment. One of the two regioisomers produced under heating conditions showed higher α-glucosidase inhibitory activity than the dominant anisoyl kaempferol glycoside.
This rearrangement reaction was also observed upon the heat treatment of methyl-3-O-anisoyl-rhamnose, with the rearrangement from the 3-position to the 2-position occurring preferentially. The approach adopted in this study can be used to design appropriate food processing conditions, which, in turn, will increase the functional value of foods.

Inactivation of Jack Bean Urease by Nitidine Chloride from Zanthoxylum nitidum: Elucidation of Inhibitory Efficacy, Kinetics and Mechanism

  • Urease is a metalloenzyme that catalyzes the hydrolysis of urea into ammonia and carbon dioxide, which has a negative impact on human health and agriculture. In this study, the inactivation of jack bean urease by nitidine chloride (NC) was investigated to elucidate the inhibitory effect, kinetics, and underlying mechanism of action. The results showed that NC acted as a concentration- and time-dependent inhibitor with an IC50 value of 33.2 ± 4.8 μM and exhibited a similar inhibitory effect to acetohydroxamic acid (IC50 = 32.1 ± 5.8 μM).
  • Further kinetic analysis demonstrated that NC was a slow-binding and non-competitive inhibitor for urease. Thiol-blocking reagents (dithiothreitol, glutathione, and l-cysteine) significantly retarded urease inactivation, while Ni2+ competitive inhibitors (boric acid and sodium fluoride) synergetically suppressed urease with NC, suggesting that the active site sulfhydryl groups were possibly obligatory for NC blocking urease.
  • Molecular docking simulation further argued its inhibition mechanism. Additionally, NC-induced deactivation of urease was verified to be reversible since the inactivated enzyme could be reactivated by glutathione. Taking together, NC was a non-competitive inhibitor targeting the thiol group at the active site of urease with characteristics of concentration dependence, reversibility, and slow binding, serving as a promising novel urease suppressant

Hybrid Multivalent Jack Bean α-Mannosidase Inhibitors: The First Example of Gold Nanoparticles Decorated with Deoxynojirimycin Inhitopes

Among carbohydrate-processing enzymes, Jack bean α-mannosidase (JBα-man) is the glycosidase with the best responsiveness to the multivalent presentation of iminosugar inhitopes. We report, in this work, the preparation of water dispersible gold nanoparticles simultaneously coated with the iminosugar deoxynojirimycin (DNJ) inhitope and simple monosaccharides (β-d-gluco- or α-d-mannosides).
The display of DNJ at the gold surface has been modulated (i) by using an amphiphilic linker longer than the aliphatic chain used for the monosaccharides and (ii) by presenting the inhitope, not only in monomeric form, but also in a trimeric fashion through combination of a dendron approach with glyconanotechnology. The latter strategy resulted in a strong enhancement of the inhibitory activity towards JBα-man, with a Ki in the nanomolar range (Ki = 84 nM), i.e., more than three orders of magnitude higher than the monovalent reference compound.

Complete genome sequence of a recombinant isolate of yambean mosaic virus from Canavalia ensiformis

The complete genome sequence of a Brazilian isolate of yambean mosaic virus (YBMV) is presented. High-throughput sequencing (Illumina HiSeq) and Sanger sequencing revealed the complete genome sequence of the YBMV-BRA-6 isolate, found in Canavalia ensiformis. The de novo contigs were assembled into a 9612 nucleotides (nt) long scaffold, excluding the 3′-terminal poly(A) tail, covering the complete genome. The genomic RNA contains an open reading frame (ORF) typical of members of the genus Potyvirus, family Potyviridae, encoding a large putative polyprotein of 3078 amino acids (aa) and a small overlapping PIPO ORF.
Pairwise comparisons showed that the YBMV-BRA-6 isolate sequence shares 88.1% nt identity for the complete genome and 90.6% aa identity for the polyprotein with the YBMV-SR isolate. Phylogenetic analysis grouped both isolates together and close to bean common mosaic virus (BCMV). The polyprotein cleavage sites were predicted and a recombination event is described.
Structural and biochemical analyses of concanavalin A circular permutation by jack bean asparaginyl endopeptidase

Over 30 years ago, an intriguing post-translational modification was found responsible for creating concanavalin A (conA), a carbohydrate-binding protein from jack bean (Canavalia ensiformis) seeds and a common carbohydrate chromatography reagent. ConA biosynthesis involves what was then an unprecedented rearrangement in amino-acid sequence, whereby the N-terminal half of the gene-encoded conA precursor is swapped to become the C-terminal half of conA. Asparaginyl endopeptidase (AEP) was shown to be involved, but its mechanism was not fully elucidated.
To understand the structural basis and consequences of circular permutation, we generated recombinant jack bean conA precursor (pro-conA) plus jack bean AEP (CeAEP1) and solved crystal structures for each to 2.1 Å and 2.7 Å, respectively. By reconstituting conA biosynthesis in vitro, we prove CeAEP1 alone can perform both cleavage and cleavage-coupled transpeptidation to form conA. CeAEP1 structural analysis reveals how it is capable of carrying out both reactions. Biophysical assays illustrated that pro-conA is less stable than conA. This observation was explained by fewer intermolecular interactions between subunits in the pro-conA crystal structure and consistent with a difference in the prevalence for tetramerisation in solution. These findings elucidate the consequences of circular permutation in the only post-translation example known to occur in nature.

Native Jack bean Urease

PHAM-180 Creative Enzymes 125ku 270 EUR

Concanavalin A Lectin from Canavalia ensiformis (Jack bean), purified and low endotoxin for cell culture

CONA15-N Alpha Diagnostics 5 mg 408 EUR

Locust bean gum

GC1233-100G Glentham Life Sciences 100 g 50 EUR

Locust bean gum

GC1233-250G Glentham Life Sciences 250 g 62 EUR

Locust bean gum

GC1233-500G Glentham Life Sciences 500 g 86 EUR

Trypsin Inhibitor, Lima Bean

TLS002829 Bio Basic 100mg 185.72 EUR

Soy Bean P34 Protein

20-abx260178 Abbexa
  • 885.00 EUR
  • 342.00 EUR
  • 1609.00 EUR
  • 0.5 mg
  • 100 ug
  • 1 mg

Soy Bean p34 Recombinant protein

00901-V-01mg Virogen 0,1 mg 267.5 EUR

Soy Bean p34 Recombinant protein

00901-V-1000ug Virogen 1000 ug 1282.5 EUR

Polyclonal BEAN Antibody (N-term)

APR11508G Leading Biology 0.1ml 484 EUR

Recombinant Soy Bean P34 Protein

7-07075 CHI Scientific 100µg Ask for price

Recombinant Soy Bean P34 Protein

7-07076 CHI Scientific 500µg Ask for price

Recombinant Soy Bean P34 Protein

7-07077 CHI Scientific 1000µg Ask for price

Soy Bean P34 Protein Protein

20-abx260180 Abbexa
  • 885.00 EUR
  • 342.00 EUR
  • 1609.00 EUR
  • 0.5 mg
  • 100 ug
  • 1 mg

Locust bean gum, pure, 2400 - 2800 cps

GC0918-1KG Glentham Life Sciences 1 kg 134 EUR

Lectin from Phaseolus vulgaris (red kidney bean)

abx082468-5mg Abbexa 5 mg 203 EUR

Recombinant Soy Bean P34 Protein, His Tag

7-07078 CHI Scientific 100µg Ask for price

Recombinant Soy Bean P34 Protein, His Tag

7-07079 CHI Scientific 500µg Ask for price

Recombinant Soy Bean P34 Protein, His Tag

7-07080 CHI Scientific 1000µg Ask for price

Bean 3'UTR Luciferase Stable Cell Line

TU201300 ABM 1.0 ml Ask for price

Bean 3'UTR GFP Stable Cell Line

TU251300 ABM 1.0 ml Ask for price

Ricinus communis (castor bean) Agglutinin (RCA120)-biotin conjugate

RCA15-BTN Alpha Diagnostics 0.5 ml 225 EUR

Ricinus communis (castor bean) Agglutinin (RCA120)-FITC conjugate

RCA15-FITC Alpha Diagnostics 0.5 ml 225 EUR

Ricinus communis (castor bean) Agglutinin (RCA120)-HRP conjugate

RCA15-HRP Alpha Diagnostics 0.5 ml 286 EUR

Ricinus communis (castor bean) Agglutinin (RCA120), purified, unlabeled

RCA15-UL Alpha Diagnostics 1 mg 164 EUR

Genomic DNA from Plant Normal Tissue: Soy bean

D1634370 Biochain 10 ug 222 EUR

Total RNA from Plant Normal Tissue: Soy bean

R1634370 Biochain 100 ug 558 EUR

Brain-Expressed Protein Associating With Nedd4 Homolog (BEAN) Antibody

abx027381-400ul Abbexa 400 ul 523 EUR

Neurotoxic and convulsant effects induced by Jack Bean Ureases on the Mammalian Nervous System

Ureases are microbial virulence factors either because of the enzymatic release of ammonia or due to many other non-enzymatic effects. Here we studied two neurotoxic urease isoforms, Canatoxin (CNTX) and Jack Bean Urease (JBU), produced by the plant Canavalia ensiformis, whose mechanisms of action remain elusive. The neurotoxins provoke convulsions in rodents (LD50 ∼2 mg/kg) and stimulate exocytosis in cell models, affecting intracellular calcium levels. Here, electrophysiological and brain imaging techniques were applied to elucidate their mode of action.
While systemic administration of the toxins causes tonic-clonic seizures in rodents, JBU injected into rat hippocampus induced spike-wave discharges similar to absence-like seizures. JBU reduced the amplitude of compound action potential from mouse sciatic nerve in a tetrodotoxin-insensitive manner. Hippocampal slices from CNTX-injected animals or slices treated in vitro with JBU failed to induce long term potentiation upon tetanic stimulation. Rat cortical synaptosomes treated with JBU released L-glutamate. JBU increased the intracellular calcium levels and spontaneous firing rate in rat hippocampus neurons. MicroPET scans of CNTX-injected rats revealed increased [18]Fluoro-deoxyglucose uptake in epileptogenesis-related areas like hippocampus and thalamus.
Curiously, CNTX did not affect voltage-gated sodium, calcium or potassium channels currents, neither did it interfere on cholinergic receptors, suggesting an indirect mode of action that could be related to the ureases’ membrane-disturbing properties. Understanding the neurotoxic mode of action of C. ensiformis ureases could help to unveil the so far underappreciated relevance of these toxins in diseases caused by urease-producing microorganisms, in which the human central nervous system is affected.

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