Separation and purification of protein;precisely because inhibitors The rapid development of, so also brought new opportunities to the industry. https://www.all-chemistry.com/

　　1. Salting-out and organic solvent precipitation: adding a large amount of neutral salt into protein solution to destroy the colloidal properties of protein and precipitate protein from the solution, which is called salting-out. Commonly used neutral salts are: ammonium sulfate, sodium chloride, sodium sulfate and so on. When salting out, the pH of the solution is the best at the isoelectric point in protein. Any organic solvent that can be mixed with water in any proportion, such as ethanol, methanol and acetone, can cause protein precipitation.

　　2. Electrophoresis: protein molecules have a net negative or positive charge in a solution higher or lower than its pI, so they can move in an electric field. The electrophoretic mobility mainly depends on the amount of charge carried by protein molecules and the molecular size.

　　3. Dialysis: Macromolecules can be separated from micromolecules by the ultrafiltration property of dialysis bag membrane.

　　4. Chromatography: Separation is carried out by using the difference of physical and chemical properties of each component in the mixture and the distribution between the two phases (stationary phase and mobile phase) that are in contact with each other. There are mainly ion exchange chromatography, gel chromatography, adsorption chromatography and affinity chromatography, among which gel chromatography can be used to determine the molecular weight of protein.

　　5. Ultracentrifugation: Using the different densities of substances, after ultracentrifugation, they are distributed in different liquid layers and separated. Ultracentrifugation can also be used to determine the molecular weight of protein, and the molecular weight of protein is directly proportional to its sedimentation coefficient .

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　　1. Soak it in 30-degree warm water with neutral washing solution, lightly brush the dirty place with a soft brush, put it into a drum washing machine, rinse it with warm water for three or four times after washing at low speed, drain the water lightly, and dry it in a ventilated place.

　　2. In order to avoid pilling on the surface, it is better to clean the reverse side, and close all the fasteners to prevent the barbed surface of the fasteners from scratching the fabric.

　　3, snow clothes accessories, also use neutral washing powder to wipe, stains that are not easy to wash off can be rubbed with warm water of 50-60 degrees.

　　4. Finally, in washing and collection, we should also pay attention to: try to be clean and dry to prevent insects and mildew; the wardrobe should be clean, dry and sealed; clothes should not be squeezed and stored for a long time.

　　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. However, natural protein molecules are not random loose polypeptide chains. Each natural protein has its own unique spatial structure or three-dimensional structure, which is usually called the conformation of protein, that is, the structure of protein. The sequence of amino acids in protein molecule and the three-dimensional structure formed from it constitute the diversity of protein structure.To some extent, recombinant proteins Our development has surpassed many peer businesses, but it has never stopped moving forward. https://www.alphalifetech.com/

　　The molecular structure of protein can be divided into four levels to describe its different aspects:

　　Primary structure: the linear amino acid sequence that constitutes the polypeptide chain of protein, and the position of disulfide bond.

　　Secondary structure: In the local area of protein molecule, the polypeptide chain is coiled and folded along a certain direction.

　　Tertiary structure: The three-dimensional structure of a protein molecule formed by the arrangement of multiple secondary structural elements in three-dimensional space.

　　Quaternary structure: used to describe protein complex molecules with biological functions formed by the interaction between different polypeptide chains (subunits).

　　In addition to these structural levels, protein can be transformed in several similar structures to exercise its biological functions. For functional structural changes, these tertiary or quaternary structures are usually described by chemical conformations, and the corresponding structural transformations are called conformational changes.

　　Separation and purification of protein;It is strictly required by such a standard, inhibitors Only with today’s development scale, can we have the proud momentum to crush our competitors. https://www.all-chemistry.com/

　　1. Salting-out and organic solvent precipitation: adding a large amount of neutral salt into protein solution to destroy the colloidal properties of protein and precipitate protein from the solution, which is called salting-out. Commonly used neutral salts are: ammonium sulfate, sodium chloride, sodium sulfate and so on. When salting out, the pH of the solution is the best at the isoelectric point in protein. Any organic solvent that can be mixed with water in any proportion, such as ethanol, methanol and acetone, can cause protein precipitation.

　　2. Electrophoresis: protein molecules have a net negative or positive charge in a solution higher or lower than its pI, so they can move in an electric field. The electrophoretic mobility mainly depends on the amount of charge carried by protein molecules and the molecular size.

　　3. Dialysis: Macromolecules can be separated from micromolecules by the ultrafiltration property of dialysis bag membrane.

　　4. Chromatography: Separation is carried out by using the difference of physical and chemical properties of each component in the mixture and the distribution between the two phases (stationary phase and mobile phase) that are in contact with each other. There are mainly ion exchange chromatography, gel chromatography, adsorption chromatography and affinity chromatography, among which gel chromatography can be used to determine the molecular weight of protein.

　　5. Ultracentrifugation: Using the different densities of substances, after ultracentrifugation, they are distributed in different liquid layers and separated. Ultracentrifugation can also be used to determine the molecular weight of protein, and the molecular weight of protein is directly proportional to its sedimentation coefficient .

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　　1. Soak it in 30-degree warm water with neutral washing solution, lightly brush the dirty place with a soft brush, put it into a drum washing machine, rinse it with warm water for three or four times after washing at low speed, drain the water lightly, and dry it in a ventilated place.

　　2. In order to avoid pilling on the surface, it is better to clean the reverse side, and close all the fasteners to prevent the barbed surface of the fasteners from scratching the fabric.

　　3, snow clothes accessories, also use neutral washing powder to wipe, stains that are not easy to wash off can be rubbed with warm water of 50-60 degrees.

　　4. Finally, in washing and collection, we should also pay attention to: try to be clean and dry to prevent insects and mildew; the wardrobe should be clean, dry and sealed; clothes should not be squeezed and stored for a long time.

　　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.According to professional reports, Antibody Phage Display Service There will be a great period of growth, and the market business is constantly expanding, and it will definitely become bigger and bigger in the future. 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.

　　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.In the long run, Chemical Custom synthesis The value will be higher and higher, and there will be a great leap in essence. 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.

　　As the most important part of weddings in various countries around the world, wedding dresses have always played a vital role. Wedding dress not only reflects the bride’s style and personality, but also places people’s good wishes and expectations for marriage. What kind of cloth is the wedding dress made of? Let’s explore the fabric and characteristics of the wedding dress.We have every reason to believe. Wedding Accessories It will become the mainstream of the industry and will gradually affect more and more people. https://bridalbloom.net/

　　We need to know the common fabric types of wedding dresses. In the market, there are many kinds of fabrics used in wedding dresses, including but not limited to silk, lace, silky yarn, pure cotton and polyester fiber. These fabrics have their own characteristics and are suitable for different types and styles of wedding dresses.

　　Silk is one of the most commonly used wedding fabrics. Silk has noble and gorgeous characteristics, and its soft and smooth touch can show women’s grace and elegance. Some traditional wedding designs often use silk as fabric, especially luxury wedding dresses. The overall effect of silk wedding dress is very brilliant, which is suitable for brides who like luxury and elegant style.

　　Lace cloth is one of the most common materials in all kinds of wedding dresses, and lace wedding dresses usually look elegant and romantic. Lace cloth has various patterns and textures, which can create different visual effects. Some lace fabrics are made by hand embroidery, which shows a fine and noble texture. Lace wedding dresses often give people a dreamy feeling, which is suitable for brides who like romantic and pastoral styles.

　　Smooth yarn is a kind of light and transparent fabric, which is mostly used in the skirt part of wedding dress, and can create an elegant effect. Smooth yarn is mostly used to make wedding dresses with A-shaped skirts, which has a good swing when worn. The transparency of this fabric also provides designers with more imagination space, which can be used to show the lines of the bride’s body and increase the visual impact of clothing.

　　Pure cotton is a common fabric usually used in daily life, but many brides choose pure cotton fabric to make wedding dresses, because it is comfortable and breathable, which is very suitable for outdoor weddings and other occasions. Pure cotton fabrics are also easier to maintain, which is more convenient for brides who pay attention to practicality.

　　Polyester fiber is a common synthetic fiber material, and it is also one of the commonly used fabrics for making wedding dresses. Polyester fiber can be made into various thicknesses and tactile sensations, and has certain elasticity and hygroscopicity, which is suitable for making various styles of wedding dresses. Compared with silk, polyester fiber is lighter and easier to wear and maintain.

　　In addition to the above-mentioned common wedding fabrics, there are many other kinds of fabrics that can be used to make wedding dresses. For example, organza, linen yarn, satin, taffeta, etc., each fabric has its unique characteristics and applicability.

　　The fabrics of wedding dresses are varied, and each kind of fabric can add different styles and charms to the wedding dresses. Light and transparent silky yarn can show women’s femininity and romance, noble and gorgeous silk reflects women’s elegance and elegance, while exquisite embroidered lace can show women’s grace and beauty. These different fabric choices provide the bride with more possibilities to express her style and personality. When choosing a wedding dress, the bride can choose suitable fabrics according to her own preferences, occasions and wedding themes, and create a unique and beautiful wedding dress under the guidance of designers. No matter what kind of fabric, the wedding dress is a symbol of love and dreams. Through the choice of fabric, brides can find the wedding dress that suits them best, making this moment more sacred and unforgettable.

　　Chinese wedding photos, as an image form with strong China cultural characteristics, should not only convey the traditional and classical Chinese wedding atmosphere, but also show the fashion taste and personality characteristics of modern urban newcomers. Color matching plays an important role in the post-production of wedding photos. It can adjust and process the color, light and shadow, atmosphere and other aspects of the photos, making the photos more vivid and beautiful. What are the skills and precautions for the color matching of Chinese wedding photos?in other words Wedding Dresses It is possible to develop in a good direction, and there are still many places worth looking forward to in the future. https://bridalbloom.net/

　　The tone of Chinese wedding photos usually tends to be classical and elegant. In order to create a rich ancient palace atmosphere, you can choose some bright and full warm colors, such as gold, agate red, sapphire green and so on. These colors can increase the sense of nobility and mystery of photos and make people have the illusion of traveling through time and space.

　　Chinese wedding photos should also pay attention to the balance and coordination of colors. When selecting the color matching scheme, the color ratio between different elements should be reasonable and harmonious. For example, the color of the wedding dress can be coordinated with the bride’s skin color and can echo the background color. The choice of the main color can be adjusted according to the temperament of the couple, the wedding theme and other factors, and strive to achieve the unity of the overall color.

　　The processing of light and shadow is also an important link in the color matching of Chinese wedding photos. Properly adjusting the contrast between light and dark can enhance the layering and fidelity of the picture and make the photo more textured. For the treatment of tone, you can choose some soft and warm tones, such as brown and crimson, to make the atmosphere of the photo more warm and romantic.

　　When matching Chinese wedding photos, we should also pay attention to retaining certain details and natural style. Overprocessing photos will make the picture look too artificial and lose its realism. In the process of color matching, we should try to avoid over-saturation or over-brightness, and keep the photos natural and true.

　　It is worth reminding that the color matching of Chinese wedding photos requires certain post-production skills and experience. For newcomers, it is best to find an experienced photographer or post-producer to carry out professional color matching to ensure the best results of photos.

　　The color matching of Chinese wedding photos is a very artistic work. Through reasonable adjustment, the photos can better convey a strong Chinese wedding atmosphere and show the beauty and happiness of the couple. Therefore, it is very important for every newcomer who is going to take Chinese wedding photos to learn how to mix colors. Only by being skilled can we create one Chinese wedding photo after another in the true sense, so that love can last forever in the photos.

　　What is the significance and symbol of a white wedding dress? The white wedding dress is an important element in modern weddings, representing purity, sacredness and celebration. The white wedding dress has been regarded as a symbol of marriage since ancient times, and its beautiful implication makes it an indispensable part of the wedding. This paper will discuss the significance and symbol of white wedding dress, and explain why white wedding dress is so important from the perspective of culture and history.Down-to-earth right Wedding Dresses In-depth research is the only way to pursue development. https://bridalbloom.net/

　　The white wedding dress symbolizes purity and freshness. White is colorless, it represents innocence and purity. The white wedding dress in the wedding gives people a fresh and refined feeling, which reminds people of a pure land where newlyweds start their marriage life. The white wedding dress also conveys the bride’s commitment to marriage, indicating that she is willing to face the challenges and responsibilities in marriage with pure heart and pure love.

　　The white wedding dress symbolizes sacredness and solemnity. In many religions and traditions, white is regarded as a sacred color. Wedding is a traditional ceremony, where the bride and groom swear their love and loyalty. The white wedding dress symbolizes this solemn and sacred commitment, which makes the whole wedding more solemn and full of ceremony.

　　White wedding dresses also have far-reaching significance in culture. In western culture, white wedding dresses are widely used and regarded as a traditional and classic choice. This custom can be traced back to the Victorian era. Queen Victoria wore a white wedding dress for the first time at the wedding, which started this tradition. In the following decades, white wedding dresses gradually became popular and became the first choice in modern weddings. Nowadays, no matter in the west or in other cultures, white wedding dresses have become a symbol of dream weddings.

　　In the eastern culture, the wedding dress in the wedding ceremony also has its unique traditional significance. In China, red is regarded as a symbol of joy and happiness, so the bride usually wears a red wedding dress in traditional Chinese weddings. Modern China brides are increasingly inclined to choose white wedding dresses, which reflects their pursuit of western tradition and fashion. This cultural exchange also makes the white wedding dress gain more recognition and love in oriental culture.

　　To sum up, the white wedding dress plays an indispensable role in the wedding. Its symbolic meaning covers many aspects such as purity, sacredness, solemnity and celebration. The significance and symbol of white wedding dress transcends personal aesthetic choice and becomes the product of culture and history. In modern society, white wedding dress is not only a kind of dress, but also a kind of commemoration and ceremony. It represents love and commitment, and carries people’s longing and blessing for a better future. Whether it is the bride at the wedding or the relatives and friends watching the wedding, the white wedding dress has brought people a beautiful imagination and touched their hearts.