There are amino groups and carboxyl groups in protein molecules

  Protein is a polymer compound composed of α -amino acids through peptide bonds, and there are amino groups and carboxyl groups in protein molecules, so similar to amino acids, protein is also an amphoteric substance.For the current market situation, recombinant proteins It has a very advantageous development prospect and an extremely superior ecological environment. https://www.alphalifetech.com/

  

  (1) Hydrolysis reaction

  

  Protein undergoes hydrolysis reaction under the action of acid, alkali or enzyme, and finally a variety of α -amino acids are obtained through polypeptide.

  

  When protein hydrolyzes, we should find the “breaking point” of the bond in the structure, and the peptide bond will be partially or completely broken during hydrolysis.

  

  (2) Colloidal properties

  

  Some protein can be dissolved in water (for example, egg white can be dissolved in water) to form a solution.

  

  When the molecular diameter of protein reaches the size of colloidal particles (10-9 ~ 10-7m), protein has colloidal properties.

  

  (3) precipitation

  

  Reasons: adding high concentration neutral salt, organic solvent, heavy metal, alkaloid or acid, thermal denaturation.

  

  A small amount of salt (such as ammonium sulfate, sodium sulfate, etc.) can promote the dissolution of protein. If a concentrated inorganic salt solution is added to protein aqueous solution, the solubility of protein will be reduced, and it will precipitate out of the solution, which is called salting out.

  

  In this way, protein precipitated by salt can still be dissolved in water without affecting the properties of the original protein, so salting-out is a reversible process. Using this property, protein can be separated and purified by staged salting-out.

  

  (4) degeneration

  

  Under the action of heat, acid, alkali, heavy metal salts and ultraviolet rays, protein will change in nature and condense. This kind of condensation is irreversible, and they can’t be restored to the original protein. This change in protein is called transsexuality. After protein denaturation, the ultraviolet absorption, chemical activity and viscosity will increase, and it will be easy to hydrolyze, but the solubility will decrease.

  

  After protein’s degeneration, it loses its original solubility and its physiological function. Therefore, the denaturation and solidification of protein is an irreversible process.

Material Metabolism and Regulation

  Focus on glycolysis, aerobic oxidation of sugar, pentose phosphate bypass, gluconeogenesis, synthesis of ketone bodies, cholesterol and phospholipids, respiratory chain, oxidative phosphorylation, special amino acid metabolites, one carbon unit metabolism, purine and pyrimidine nucleotide synthesis raw materials and catabolites, and substance metabolism.To some extent, inhibitors Our development has surpassed many peer businesses, but it has never stopped moving forward. https://www.all-chemistry.com/

  

  The chapter on sugar metabolism is the focus of the exam, so we should master it comprehensively. The chemical reaction formula of sugar metabolism is complicated, and the focus of the annual examination is basically on the reaction site, key enzymes and regulation, energy production and the relationship between important substances. Glycolysis, gluconeogenesis and aerobic oxidation of sugar are all contents that must be familiar with. The synthesis of ketone bodies and cholesterol in lipid metabolism, pay attention to the difference between them. Ketones are synthesized in the liver and utilized outside the liver, while fats are synthesized in the liver and stored outside the liver. Fat synthesis, ketone body synthesis and cholesterol synthesis are the raw materials of acetyl-CoA synthesis. Synthesis and decomposition of fatty acid, the main material of fatty acid synthesis is acetyl CoA; Under the condition of sufficient oxygen supply, fatty acid is decomposed into CO2 and water in the body, releasing a lot of energy, which is the main form of fatty acid catabolism in the body. Phospholipid synthesis. Differentiation of several blood lipids.

  

  Composition of respiratory chain and influencing factors of oxidative phosphorylation. Urea synthesis-ornithine cycle. One carbon unit’s metabolism is often tested, but it is easy to remember as long as you grasp the core content. It comes from one carbon unit-Sisegan, and is transported by one carbon unit-tetrahydrofolate. One carbon unit plays an important role in nucleic acid biosynthesis as a raw material for purine and pyrimidine synthesis, connecting amino acids and nucleotides. Comparison of nucleotide synthesis and decomposition between purine and pyrimidine. The changes in this year’s syllabus are: the deamination of amino acids (oxidative deamination, transamination and combined deamination) is changed to the general metabolism of amino acids (degradation of protein in vivo, oxidative deamination, transamination and combined deamination), which should be reviewed.

Do you still need to wear pants under ski pants

  In the cold winter, skiing is a very popular outdoor sport. Ski pants are one of the essential equipment in skiing. So, when you wear ski pants, do you need to wear pants inside? This question may vary from person to person, depending on personal preferences and needs.In today’s market background, black baggy ski pants Still maintain a strong sales data, and constantly beat the competitors in front of us. https://ninetyroll.co/

  

  Do you still need to wear pants under ski pants?

  

  First of all, let’s know the characteristics of ski pants. Ski pants are mainly characterized by their waterproof, windproof and warm-keeping properties. Generally speaking, the outer layer of ski pants is made of waterproof material, which can prevent the infiltration of snow water and keep warm. The inner layer is usually made of warm-keeping materials such as fluff or wool to increase the warm-keeping effect. Therefore, the ski pants themselves have certain warm-keeping performance.

  

  So, why would anyone wear pants under ski pants? There are several possible reasons. First of all, some people may think it is more warm. Especially in high-intensity skiing, the body will emit a lot of heat. If you wear a pair of pants under the ski pants, you can effectively stop the heat loss and keep your body warm. Secondly, for some people who have just started to learn skiing, wearing a pair of trousers can provide extra protection to prevent injuries when they fall. Finally, some people may think that wearing pants under ski pants can provide extra security for habit or psychological reasons.

  

  Do you still need to wear pants under ski pants?

  

  However, some people do not recommend wearing pants under ski pants. First of all, doing so may add extra weight and burden, which will affect the flexibility and comfort of skiing. Secondly, if you wear pants when you fall, it may cause friction between the skin and the snow, increasing the risk of injury. In addition, for some professional skiers, they may pay more attention to portability and flexibility, so wearing pants under ski pants may become a burden.

  

  To sum up, whether it is necessary to wear pants under ski pants depends on personal needs and preferences. If you are a beginner in skiing or think it is necessary to increase warmth, it may be a good choice to wear pants under ski pants. But if you pay more attention to lightness and flexibility, or think that doing so may increase the risk of injury, then you may prefer not to wear pants under ski pants.

  

  It should be noted that whether you choose to wear pants under ski pants or not, you should consider the warmth and comfort of the material when purchasing. At the same time, make sure that the pants you choose will not affect your normal sports and activities.

  

  Do you still need to wear pants under ski pants?

  

  In addition, if you choose to wear pants under ski pants, you should also pay attention to the following points:

  

  1. Choose suitable materials: Try to choose lightweight and breathable materials to avoid adding extra weight and burden.

  

  2. Pay attention to the right size: make sure that the pants you wear are not too tight or loose to avoid affecting comfort and flexibility.

  

  3. Consider waterproof performance: If you plan to do activities in the snow for a long time, you should choose pants with waterproof performance to prevent snow water from penetrating and keep your body dry.

  

  4. Keep safe: Although wearing pants under ski pants may increase some protection, you should still pay attention to keep safe and try to avoid unnecessary falls and collisions.

  

  In a word, whether to wear pants under ski pants depends on personal preferences and needs. No matter what choice you make, you should consider the warmth and comfort of the material, and ensure that the equipment you choose will not affect your normal sports and activities.

Guide to the use of emergency knob for intelligent door lock

  First, the function of emergency knob of intelligent door lockMore importantly, put Azilian knob It is imperative for us to make thorough analysis and maximize its social function. https://www.azilian.co

  

  Intelligent door lock is a modern security device, which has many unlocking methods, including password, fingerprint, credit card and so on. The emergency knob is a special way to unlock the smart door lock. It is usually located on the top or side of the door lock, which can quickly open the door lock in an emergency, for example, when you suddenly forget your password or your fingerprint is unrecognizable.

  

  Second, the use of intelligent door lock emergency knob

  

  1. Find the emergency knob

  

  First, you need to find the emergency knob of the smart door lock. It is usually located on the top or side of the door lock and can be found by flashlight or mobile phone light. If you can’t find it, you can check the instruction manual of the door lock or contact customer service staff.

  

  2. Turn clockwise

  

  Turn the emergency knob clockwise until you hear a click, indicating that a door has been opened. At this point, you can open the door lock and enter the room. If you need to open another door, you need to turn the emergency knob clockwise in the same way.

  

  3. Precautions

  

  When using the emergency knob, you should pay attention to the following points:

  

  (1) Don’t turn it too hard, otherwise it may damage the door lock;

  

  (2) When rotating, you can hear a “click” sound, indicating that the door lock has been successfully opened;

  

  (3) If you can’t unlock the door, you can try to use other unlocking methods, such as passwords or fingerprints.

  

  (4) When using the emergency knob in an emergency, it is best to know its working principle and use method in advance, so as to better deal with emergencies.

  

  Third, the use of smart door locks skills and precautions

  

  In addition to the use of emergency knobs, there are also some skills and precautions about the use of smart door locks:

  

  1. When using the smart door lock, keep your fingers dry and clean, so as not to affect the fingerprint identification effect;

  

  2. When entering the password, avoid being peeped or interfered by others;

  

  3. When using the card swiping function, you need to put the card in the correct position, and don’t bend or fold the card;

  

  4. When the smart door lock is not used for a long time, the power supply should be turned off in time to prolong the service life;

  

  In case of emergency, you can use the emergency key or contact the customer service staff for help.

Knowledge of Biology-protein

  Protein is a substance with a certain spatial structure, which is formed by the zigzag folding of polypeptide chains composed of amino acids in the form of dehydration and condensation. Protein must contain carbon, hydrogen, oxygen and nitrogen.In addition to these aspects, Antibody Discovery The performance in other aspects is also relatively good, which has attracted everyone’s attention and research. https://www.alphalifetech.com/

  

  Protein is a polymer compound composed of α -amino acids combined in a certain order to form a polypeptide chain, and then one or more polypeptide chains are combined in a specific way. Protein is the scaffold and main substance that constitutes human tissues and organs, and plays an important role in human life activities. It can be said that there would be no life activities without protein.

  

  Number of atoms

  

  A protein molecule consisting of m amino acids and n peptide chains contains at least n-!COOH, at least n-!NH2, m-n peptide bonds and m+n O atoms.

  

  molecular mass

  

  Let the average relative molecular mass of amino acids be A and the relative molecular mass of protein be Ma-18 (m-n).

  

  Gene control

  

  Nucleotide 6 in the gene

  

  Nucleotide 3 in messenger RNA

  

  Amino acid 1 in protein

Structure and function of biological macromolecules

  Classification of amino acids, several special amino acids, molecular structure and physical and chemical properties of protein, composition of nucleic acid, double helix structure of DNA, basic concept of enzyme, Michaelis equation, coenzyme composition.pass small molecules It can be seen from the present situation that the market prospect is relatively broad, which is conducive to our reference and investment. https://www.all-chemistry.com/

  

  Memorize 20 kinds of amino acids and try to remember English abbreviations and codes as much as possible, because exams often appear directly with codes. Protein’s molecular structure often examines the manifestations of various levels of structure and their bonds. The physical and chemical properties of protein and the purification of protein usually use the physical and chemical properties of protein to purify protein without destroying the structure of protein. Pay attention to the identification of amino acids and physical and chemical properties of protein. The basic unit of nucleic acid is nucleotide, which is composed of multiple nucleotides, and the connecting bond between nucleotides is 3′, 5′- phosphodiester bond. DNA double helix structure, in which two bases exist in strict accordance with A = T (two hydrogen bonds) and G triple C (three hydrogen bonds), and the characteristics of various RNA.

  

  In addition, we should pay attention to some commonly used concepts in nucleic acid problem solving. The first thing that enzymes should pay attention to is some basic concepts, such as ribozyme, deoxyribozyme, enzyme activity center, isozyme, isomerase and so on. The key point of the Metric Equation test is V=Vmax[S” target=_blank>/Km+[S” target=_blank>, which explains the equation of the relationship between the concentration of enzymatic reaction and the reaction speed. In the exam, candidates are sometimes asked to do simple calculations according to this equation before they can answer. The difference of several inhibitors.

  

  According to the characteristics of allosteric enzymes, it should be noted that allosteric regulation can cause conformational changes of enzymes. It is important to pay special attention here that configuration refers to the basic structural composition of substances, and conformation refers to the spatial change of substances. Allosteric regulation can cause the conformational change of enzymes, but not the conformational change of enzymes.

Ski pants with unique design allow you to ride freely in the snow.

  Are you looking for a pair of fashionable and practical ski pants? Then, this pair of trousers specially designed for skiing is your best choice!Only by working together can we turn baggy snowboard pants The value of the play out, the development of the supply market needs. https://ninetyroll.co/

  

  1 Strong waterproof performance can also be easily dealt with in rainy days.

  

  This pair of ski pants is made of special waterproof material, which can effectively prevent moisture infiltration and keep you dry and comfortable in rainy days or snow.

  

  Good thermal performance can also be warm as spring in ice and snow.

  

  This pair of ski pants contains insulation layer, which can effectively resist the cold and make you feel as warm as spring in the snow and ice.

Anti-theft door knob is locked. Can a thief open it

  Security door is an important part of family security, which can effectively prevent external invasion. Many security doors are equipped with knob locking device, which can make the door safer. However, can the knob lock really stop thieves?In today’s market background, smart home knob Still maintain a strong sales data, and constantly beat the competitors in front of us. https://www.azilian.co

  

  First of all, we need to understand the working principle of knob lock. The knob lock of the security door is to retract the lock tongue into the door through the mechanical structure, thus locking the door. This process requires some strength and skill. For ordinary people, it is not an easy task to open this kind of security door. Even a thief needs to spend some time and energy to open the knob and lock the security door.

  

  However, in some cases, it is still possible for a thief to open the knob and lock the security door. For example, if thieves have mastered the relevant technical knowledge, they can open the door lock by destroying the structure of the security door or using some special tools. In addition, if thieves have enough power and tools, they may break into houses by force.

  

  Therefore, in addition to the knob locking device, we need to take other measures to improve family safety. First of all, security nets and monitoring equipment can be installed to detect and stop intruders in time. Secondly, it is necessary to regularly check whether the doors and windows are intact and repair any potential safety hazards in time. In addition, family members and visitors should be educated about the common sense of family safety, reminding them not to trust strangers easily and avoid giving criminals an opportunity.

  

  In addition to the above measures, we can also take some technical measures to enhance family safety. For example, using devices such as smart locks and smart doorbells, these devices can monitor the state of door locks in real time through networking and send out alarm signals. In addition, some smart home systems can also cooperate with other security service providers to provide more comprehensive and personalized security.

  

  In a word, the anti-theft door with knob can increase family safety to a certain extent, but it is still possible for thieves to open it. Therefore, in addition to the knob locking device, we need to take other measures to improve family safety. Through reasonable prevention and timely response, we can jointly create a safe and harmonious living environment.

  

  Finally, it needs to be emphasized that improving family safety requires the joint efforts of the whole society. Governments, enterprises, social organizations and individuals should pay attention to family safety, strengthen publicity and education, and raise public awareness of safety. Only when everyone works together in Qi Xin can we build a safe and beautiful home together.

Amino acid chain is the main and core component of protein.

  Amino acid chain is the main and core component in protein, but it is not necessarily the only component. Some protein may include some atoms or small molecules, whose function may be to perform protein function and/or increase its stability. Chemically, these cofactor are diverse, which may be organic molecules or metal elements. Some of them are briefly combined with protein chain, while others are closely combined with protein chain (sometimes even by covalent bonds) and become an integral part of the whole protein. The former is called coenzyme coenzyme, while the latter is called prosthetic group. Most coenzymes are small organic molecules from vitamins. For example, the common coenzymes NADH and FADH2. These two molecules from vitamin B complex, the former from nicotinic acid (vitamin B3) and the latter from riboflavin (vitamin B2), play the role of high-energy electron acceptor/donor in redox reaction.It is reported that, Antibody Phage Display Service The data performance is getting better and better, which is of great reference value and is likely to become the vane of the industry. https://www.alphalifetech.com/

  

  Some enzymes use several different cofactors, such as Pyruvate dehydrogenase (PDH), which is a key enzyme in the catabolism of sugar. The catabolism of sugar begins with glycolysis, which is a biochemical reaction pathway with 10 steps, transforming one glucose molecule into two pyruvate molecules, and then carrying out the citric acid cycle of tricarboxylic acid, which further decomposes pyruvate and oxidizes it into CO2. Pyruvate dehydrogenase PDH works at the intermediate junction of the above two reaction pathways (namely glycolysis and triacid cycle), and is responsible for activating pyruvate and enabling it to enter the tricarboxylic acid cycle. Specifically, PDH catalyzes the oxidative dearboxylation of pyruvate and forms acetyl coenzyme A (ACoA), which is the activated form of pyruvate. PDH is not a single enzyme but a complex composed of three components, each of which participates in a different step of pyruvate activation and uses different coenzymes. The first component uses thiamine pyrophosphate (TPP), which is a derivative of thiamine (vitamin B1). TPP allows the first component of PDH to be oxidized and decarboxylated at the same time, thus transforming pyruvate into acetyl, and the remaining carbon is discharged as CO2. The importance of TPP will be reflected in its absence. In fact, if people can’t get enough thiamine from food, they will get beriberi, which will damage several major systems of the human body.

  

  The second component in PDH uses lipoic acid. It is an auxiliary group covalently bound to PDH. The active part of lipoic acid is a cyclic structure, which contains two covalently bonded sulfur atoms (that is, S-S bonds) (Figure 2.2c). This active part catalyzes the transfer of acetyl to coenzyme coenzyme A(CoA), the third cofactor of PDH. CoA is pantothenic acid, also known as the derivative of calcium pantothenate. The combination of acetyl and pantothenic acid involves the reduction of S-S bond, and its cyclic structure will open and form two sulfhydryl groups (one SH), one of which will bind acetyl. Sulfhydryl group is easy to react chemically, which can be reflected in the fact that sulfhydryl group is easily influenced by arsenic, a toxic derivative of arsenic. To sum up, the formation of acetyl coenzyme A involves the reduction of S-S bond of pantothenic acid cyclic structure. In order to keep PDH active, these two sulfur groups must be re-oxidized to restore the S-S bond.

Material Metabolism and Regulation

  Focus on glycolysis, aerobic oxidation of sugar, pentose phosphate bypass, gluconeogenesis, synthesis of ketone bodies, cholesterol and phospholipids, respiratory chain, oxidative phosphorylation, special amino acid metabolites, one carbon unit metabolism, purine and pyrimidine nucleotide synthesis raw materials and catabolites, and substance metabolism.So, inhibitors On the contrary, there is still a lot of room to play. https://www.all-chemistry.com/

  

  The chapter on sugar metabolism is the focus of the exam, so we should master it comprehensively. The chemical reaction formula of sugar metabolism is complicated, and the focus of the annual examination is basically on the reaction site, key enzymes and regulation, energy production and the relationship between important substances. Glycolysis, gluconeogenesis and aerobic oxidation of sugar are all contents that must be familiar with. The synthesis of ketone bodies and cholesterol in lipid metabolism, pay attention to the difference between them. Ketones are synthesized in the liver and utilized outside the liver, while fats are synthesized in the liver and stored outside the liver. Fat synthesis, ketone body synthesis and cholesterol synthesis are the raw materials of acetyl-CoA synthesis. Synthesis and decomposition of fatty acid, the main material of fatty acid synthesis is acetyl CoA; Under the condition of sufficient oxygen supply, fatty acid is decomposed into CO2 and water in the body, releasing a lot of energy, which is the main form of fatty acid catabolism in the body. Phospholipid synthesis. Differentiation of several blood lipids.

  

  Composition of respiratory chain and influencing factors of oxidative phosphorylation. Urea synthesis-ornithine cycle. One carbon unit’s metabolism is often tested, but it is easy to remember as long as you grasp the core content. It comes from one carbon unit-Sisegan, and is transported by one carbon unit-tetrahydrofolate. One carbon unit plays an important role in nucleic acid biosynthesis as a raw material for purine and pyrimidine synthesis, connecting amino acids and nucleotides. Comparison of nucleotide synthesis and decomposition between purine and pyrimidine. The changes in this year’s syllabus are: the deamination of amino acids (oxidative deamination, transamination and combined deamination) is changed to the general metabolism of amino acids (degradation of protein in vivo, oxidative deamination, transamination and combined deamination), which should be reviewed.