Related Experiment Video
Updated: Jul 9, 2026
06:51
High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits
Published on: September 20, 2016
Xylanase inhibitors bind to nonstarch polysaccharides
Ellen Fierens1, Kurt Gebruers, Christophe M Courtin
1Laboratory of Food Chemistry and Biochemistry, Department of Microbial and Molecular Systems, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, Box 2463, 3001 Leuven, Belgium. ellen.fierens@biw.kuleuven.be
Journal of Agricultural and Food Chemistry
|December 21, 2007
Summary
Wheat xylanase inhibitors (TAXI, XIP, TLXI) bind to beta-glucans and arabinoxylans. Their binding affinity for arabinoxylans increases as the arabinose/xylose ratio decreases.
Area of Science:
- Plant biochemistry
- Food science
- Enzyme inhibition
Background:
- Xylanase inhibitors are proteins found in cereals like wheat.
- These inhibitors play a role in plant defense and can affect food processing.
- Understanding their interactions with polysaccharides is crucial for biotechnological applications.
Purpose of the Study:
- To investigate the binding interactions between wheat xylanase inhibitors (TAXI, XIP, TLXI) and various polysaccharides.
- To determine how polysaccharide structure, specifically the arabinose/xylose ratio and solubility, affects inhibitor binding.
- To elucidate the natural function of xylanase inhibitors and their impact on cereal-based processes.
Main Methods:
- Incubation of xylanase inhibitors (TAXI, XIP, TLXI) with different beta-glucans and (arabino)xylans.
- Measurement of residual xylanase inhibition activity to assess binding affinity.
- Analysis of the effect of varying arabinose/xylose ratios and polysaccharide solubility (water-extractable vs. water-unextractable) on inhibitor binding.
Main Results:
- All three wheat xylanase inhibitors (TAXI, XIP, TLXI) demonstrated binding to both beta-glucans and (arabino)xylans.
- Binding affinity for (arabino)xylans increased significantly with a lower arabinose/xylose ratio.
- This interaction was observed irrespective of whether the (arabino)xylans were water-extractable or water-unextractable.
Conclusions:
- Wheat xylanase inhibitors interact with diverse polysaccharides, including beta-glucans and (arabino)xylans.
- The structural characteristics of (arabino)xylans, particularly the arabinose/xylose ratio, are key determinants of inhibitor binding.
- These findings enhance our understanding of xylanase inhibitor function in nature and their potential effects in cereal biotechnology, such as bread making.
Related Concept Videos
01:19Oral Hypoglycemic Agents: α-Glucosidase Inhibitors
α-glucosidase inhibitors, including acarbose (Precose), miglitol (Glyset), and voglibose (Voglib) (primarily available in Asia), are drugs that control blood sugar levels by delaying the digestion of starch and disaccharides. They achieve this by inhibiting α-glucosidase enzymes in the intestine, which slow the absorption of carbohydrates in the intestine, which in turn leads to a prolonged release of the glucoregulatory hormone GLP-1 from intestinal L-cells.
Acarbose and miglitol are typically...
Acarbose and miglitol are typically...
01:30Enzyme Inhibition
Inhibitors are molecules that reduce enzyme activity by binding to the enzyme. In a normally functioning cell, enzymes are regulated by a variety of inhibitors. Drugs and other toxins can also inhibit enzymes. Some inhibitors bind to the enzyme’s active site, while others inhibit enzymatic activity by binding to other sites on the protein structure.
01:23Inhibitors of Gram-positive Cell Wall Synthesis
Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...
01:23Dipeptidyl Peptidase 4 Inhibitors
Dipeptidyl peptidase 4 (DPP-4) is a serine protease widely distributed in the body. It's involved in the inactivation of GLP-1 and GIP hormones, which are crucial for insulin regulation. DPP-4 inhibitors, such as sitagliptin (Januvia), saxagliptin (Onglyza), linagliptin (Tradjenta), alogliptin (Nesina), and vildagliptin (Galvus), help increase the proportion of active GLP-1, enhancing insulin secretion. These inhibitors work by competitively binding to DPP-4. This binding causes a significant...
01:18Indirect-Acting Cholinergic Agonists: Mechanism of Action
Indirect-acting cholinergic agonists work by interacting with an enzyme called acetylcholinesterase (AChE) in the synaptic cleft. They can be reversible or irreversible inhibitors and have different effects on the enzyme.
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex, leading to...
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex, leading to...
01:29Indirect-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
Indirect-acting cholinergic agonists are agents that interact with the acetylcholinesterase enzyme in the synaptic cleft, preventing the breakdown of acetylcholine into choline and acetate. Consequently, the concentration of acetylcholine in the synaptic cleft increases. These agonists can be classified into reversible and irreversible inhibitors based on their duration of action.
Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...
Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...