the general knowledge of in vitro diagnostic reagents
Enzyme preparations are proteins composed of amino acids produced by all living organisms, which can control many reaction processes and biological activities of fabrics, animals, humans and microorganisms. For most organics, dehydrogenation equals oxidation. Therefore, many people equate the two. However, in terms of enzyme naming, although both dehydrogenase and oxidase belong to the class of oxidoreductases, they belong to different subclasses and catalyze different types of reactions.
The reaction catalyzed by dehydrogenase is not aerobic, and the electron acceptor is a reducing coenzyme, such as NAD, NADP, or FAD, such as alcohol dehydrogenase, which catalyzes alcohol metabolism. When we study the metabolic part of biochemistry, we will encounter many dehydrogenases, which are often used to calculate the amount of ATP produced. There are four typical responses:
1. Alcohol hydroxyl groups are oxidized to produce aldehydes or ketones, such as malate dehydrogenase in the tricarboxylic acid cycle, hydroxyacyl-CoA dehydrogenase in the oxidation of fatty acids, etc.
2. Aldehyde groups are oxidized to carboxyl groups, such as glycolytic glyceraldehyde phosphate dehydrogenase, and the rate-limiting enzyme acetaldehyde dehydrogenase of alcohol metabolism also belongs to this category.
3. Decarboxylation of α-keto acid, such as pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, etc.
4. Dehydrogenation of saturated hydrocarbon chains generates double bonds, such as succinate dehydrogenase, acyl-CoA dehydrogenase, etc. These dehydrogenases generally use FAD as electron acceptor.
The electron acceptor of oxidases is molecular oxygen, and the product is water or H2O2, often requiring flavin prosthetic groups. Such as the commonly used glucose oxidase (Glucose Oxidase) when measuring blood sugar. Xanthine oxidase used in purine metabolism also belongs to this category and is a target for the treatment of gout.
Therefore, dehydrogenase and oxidase cannot be mixed. For example, glucose dehydrogenase (EC220.127.116.11) and glucose oxidase (EC18.104.22.168) are different enzymes. The former catalyzes glucose to produce gluconolactone and uses NAD or NADP as electron acceptors; the latter This produces gluconic acid and hydrogen peroxide.
Oxidoreductases are customarily divided into four subcategories. In addition to dehydrogenases and oxidases, there are the following two categories:
1. Peroxidase: It includes catalase, peroxidase and peroxygenase, with H2O2 as the receptor, and flavin and heme as prosthetic groups. Such enzymes are related to cell detoxification, oxidative stress, aging and other processes.
2. Oxygenase: catalyze the incorporation of oxygen atoms into organic molecules, including oxygenase and hydroxylase. Oxygenase can also be divided into monooxygenase and dioxygenase according to the number of oxygen atoms incorporated. Hydroxylase can introduce hydroxyl groups into organic substances, and requires hydrogen donors such as NADPH to participate in the reaction, and often participates in processes such as hormone synthesis and drug metabolism. Hydroxylase was previously classified as monooxygenase, but it is now independent.
Desheng produces a variety of enzyme preparation products. The enzyme preparation products provided are mainly used as test materials for kits. In addition to glucose dehydrogenase and glucose oxidase, there are also α-glucosidase, cholesterol esterase, cholesterol oxidase, and purine nucleosides. Phosphorylase, lactate dehydrogenase, etc. Friends in need can consult us or provide samples.
Trihydroxymethylaminomethane is an important laboratory reagent widely used in fields such as molecular biology and biochemistry. To ensure its quality and purity, a series of tests are required. This article provides measurement methods for appearance, content, solubility, drying weight loss, pH value, melting point, and UV absorbance. These methods help to evaluate the quality and purity of trimethylaminomethane.