Life and non-living things? Chemistry and biochemistry? Where is the line between them? And does she exist? Where is the connection? The key to solving these problems for a long time nature had seven locks. And only in the 20th century was it possible to somewhat reveal the secrets of life, and many fundamental questions became clearer when scientists reached research at the molecular level. Knowledge of the physicochemical foundations of life processes has become one of the main tasks of natural science, and it is in this direction that, perhaps, the most interesting results have been obtained, which have fundamental theoretical significance and promise enormous implications for practice.
Chemistry has long been looking closely at natural substances involved in life processes.
Over the past two centuries, chemistry was destined to play an outstanding role in the knowledge of living nature. At the first stage, chemical study was descriptive in nature, and scientists isolated and characterized various natural substances, waste products of microorganisms, plants and animals, which often had valuable properties (medications, dyes, etc.). However, only relatively recently this traditional chemistry of natural compounds was replaced by modern biochemistry with its desire not only to describe, but also to explain, and not only the simplest, but also the most complex in living things.
Extraorganic biochemistry
Extraorganic biochemistry as a science emerged in the middle of the 20th century, when new directions in biology, fertilized by the achievements of other sciences, burst onto the scene, and when specialists of a new mindset came to natural science, united by the desire and desire to more accurately describe the living world. And it is no coincidence that under the same roof of an old-fashioned building at 18 Akademicheskiy Proezd there were two newly organized institutes that represented the newest areas of chemical and biological science at that time - the Institute of Chemistry of Natural Compounds and the Institute of Radiation and Physico-Chemical Biology. These two institutes were destined to begin a battle in our country for knowledge of the mechanisms of biological processes and a detailed elucidation of the structures of physiologically active substances.
By this period, the unique structure of the main object of molecular biology, deoxyribonucleic acid (DNA), the famous “double helix,” became clear. (This is a long molecule on which, like on a tape or matrix, the full “text” of all information about the body is recorded.) The structure of the first protein - the hormone insulin - appeared, and the chemical synthesis of the hormone oxytocin was successfully completed.
What exactly is biochemistry and what does it do?
This science studies biologically important natural and artificial (synthetic) structures, chemical compounds - both biopolymers and low molecular weight substances. More precisely, the patterns of connection between their specific chemical structure and the corresponding physiological function. Bioorganic chemistry is interested in the fine structure of the molecule of a biologically important substance, its internal connections, the dynamics and specific mechanism of its change, the role of each of its links in performing the function.
Biochemistry is the key to understanding proteins
Bio organic chemistry belong, undoubtedly, to major successes in the study of protein substances. Back in 1973, clarification of the complete primary structure the enzyme aspartate aminotransferase, consisting of 412 amino acid residues. This is one of the most important biocatalysts of a living organism and one of the largest proteins with a deciphered structure. Later, the structure of other important proteins was determined - several neurotoxins from the venom of the Central Asian cobra, which are used in studying the mechanism of transmission of nervous excitation as specific blockers, as well as plant hemoglobin from yellow lupine nodules and the anti-leukemic protein actinoxanthin.
Rhodopsins are of great interest. It has long been known that rhodopsin is the main protein involved in the processes of visual reception in animals, and it is isolated from special systems of the eye. This unique protein receives light signals and provides us with the ability to see. It was discovered that a protein similar to rhodopsin is also found in some microorganisms, but performs a completely different function (since bacteria “do not see”). Here he is an energy machine, synthesizing energy-rich substances using light. Both proteins are very similar in structure, but their purpose is fundamentally different.
One of the most important objects of study was the enzyme involved in the implementation of genetic information. Moving along the DNA matrix, it seems to read the hereditary information recorded in it and, on this basis, synthesizes information ribonucleic acid. The latter, in turn, serves as a matrix for protein synthesis. This enzyme is a huge protein, its molecular weight approaches half a million (remember: water has only 18) and consists of several different subunits. Clarification of its structure was destined to help answer the most important question in biology: what is the mechanism for “removing” genetic information, how is the text written in DNA, the main substance of heredity, deciphered.
Peptides
Scientists are interested not only in proteins, but also in shorter chains of amino acids called peptides. Among them are hundreds of substances of enormous physiological significance. Vasopressin and angiotensin are involved in the regulation of blood pressure, gastrin controls the secretion of gastric juice, gramicidin C and polymyxin are antibiotics, which also include so-called memory substances. Enormous biological information is written in a short chain of several “letters” of amino acids!
Today we can artificially produce not only any complex peptide, but also simple proteins, such as insulin. The importance of such work is difficult to overestimate.
A method has been created comprehensive analysis spatial structure of peptides using a variety of physical and computational methods. But the complex three-dimensional architecture of the peptide determines all the specifics of its biological activity. The spatial structure of any biologically active substance, or, as they say, its conformation, is the key to understanding the mechanism of its action.
Among representatives of a new class of peptide systems - depsipeltides - a team of scientists discovered substances of a striking nature that are capable of selectively transporting metal ions through biological membranes, so-called ionophores. And the main one among them is valinomycin.
The discovery of ionophores constituted an entire era in membranology, as it made it possible to specifically change the transport of ions alkali metals- potassium and sodium - through biomembranes. The transport of these ions is associated with the processes of nervous excitation, and the processes of respiration, and the processes of reception - perception of signals external environment. Using the example of valinomycin, it was possible to show how biological systems are able to select only one ion from dozens of others, bind it into a conveniently transportable complex and transfer it across the membrane. This amazing property of valinomycin lies in its spatial structure, which resembles an openwork bracelet.
Another type of ionophore is the antibiotic gramicidin A. This is a linear chain of 15 amino acids that spatially forms a helix of two molecules, which has been found to be a true double helix. The first double helix in protein systems! And the helical structure, being embedded in the membrane, forms a kind of pore, a channel through which alkali metal ions pass through the membrane. The simplest model ion channel. It is clear why gramicidin caused such a storm in membranology. Scientists have already obtained many synthetic analogues of gramicidin, and it has been studied in detail on artificial and biological membranes. How much charm and significance there is in such a seemingly small molecule!
With the help of valinomycin and gramicidin, scientists became involved in the study of biological membranes.
Biological membranes
But the composition of membranes always includes one more main component, which determines their nature. These are fat-like substances, or lipids. Lipid molecules are small in size, but they form strong, giant assemblies that form a continuous membrane layer. Protein molecules are embedded in this layer - and here is one of the models of a biological membrane.
Why are biomembranes important? In general, membranes are the most important regulatory systems of a living organism. Now, in the likeness of biomembranes, important technical means- microelectrodes, sensors, filters, fuel cells... And further prospects for the use of membrane principles in technology are truly limitless.
Other interests in biochemistry
Research on the bichemistry of nucleic acids occupies a prominent place. They are aimed at deciphering the mechanism of chemical mutagenesis, as well as understanding the nature of the connection between nucleic acids and proteins.
Special attention has long focused on artificial gene synthesis. A gene, or, to put it simply, a functionally significant section of DNA, today can already be obtained by chemical synthesis. This is one of the important areas of “genetic engineering” that is now fashionable. Works at the intersection of bioorganic chemistry and molecular biology require mastery with the most complex techniques, friendly cooperation between chemists and biologists.
Another class of biopolymers are carbohydrates, or polysaccharides. We know typical representatives of substances in this group - cellulose, starch, glycogen, beet sugar. But in a living organism, carbohydrates perform a wide variety of functions. This is the protection of the cell from enemies (immunity), it is the most important component of cell walls, a component of receptor systems.
Finally, antibiotics. In laboratories, the structure of such important groups of antibiotics as streptothricin, olivomycin, albofungin, abikovchromycin, aureolic acid, which have antitumor, antiviral and antibacterial activity, has been clarified.
It is impossible to talk about all the searches and achievements of bioorganic chemistry. We can only say with certainty that bioorganics have more plans than things done.
Biochemistry works closely with molecular biology and biophysics, which study life at the molecular level. It became the chemical foundation of these studies. The creation and widespread use of new methods and new scientific concepts contributes to the further progress of biology. The latter, in turn, stimulates the development of chemical sciences.
What is biochemistry? Biological or physiological biochemistry is the science of chemical processes that underlie the life of an organism and those that occur inside a cell. The purpose of biochemistry (the term comes from the Greek word “bios” - “life”) as a science is the study chemical substances, structure and metabolism of cells, the nature and methods of its regulation, the mechanism of energy supply for processes within cells.
Medical biochemistry: the essence and goals of science
Medical biochemistry is a section that studies the chemical composition of cells human body, metabolism in it (including in pathological conditions). After all, any disease, even in an asymptomatic period, will inevitably leave its mark on the chemical processes in cells and the properties of molecules, which will be reflected in the results of biochemical analysis. Without knowledge of biochemistry, it is impossible to find the cause of the disease and the way to effectively treat it.
Biochemical blood test
What is a blood chemistry test? Biochemical blood testing is one of the laboratory diagnostic methods in many areas of medicine (for example, endocrinology, therapy, gynecology).
It helps to accurately diagnose the disease and examine a blood sample using the following parameters:
Alanine aminotransferase (ALAT, ALT);
Cholesterol or cholesterol;
Bilirubin;
Urea;
Diastasis;
Glucose, lipase;
Aspartate aminotransferase (AST, AST);
Gamma-glutamyl transpeptidase (GGT), gamma GT (glutamyl transpeptidase);
Creatinine, protein;
Antibodies to Epstein-Barr virus.
For the health of every person, it is important to know what blood biochemistry is, and to understand that its indicators will not only provide all the data for effective scheme treatment, but also help prevent the disease. Deviations from normal values are the first signal that something is wrong in the body.
blood for liver research: significance and goals
In addition, biochemical diagnostics will allow monitoring the dynamics of the disease and the results of treatment, creating a complete picture of metabolism, deficiency of microelements in organ function. For example, liver biochemistry will be a mandatory test for people with liver dysfunction. What is this? This is the name of a biochemical blood test to study the quantity and quality of liver enzymes. If their synthesis is impaired, then this condition threatens the development of diseases and inflammatory processes.
Specifics of liver biochemistry
Biochemistry of the liver - what is it? The human liver consists of water, lipids, and glycogen. Its tissues contain minerals: copper, iron, nickel, manganese, so the biochemical study of liver tissue is a very informative and quite effective analysis. The most important enzymes in the liver are glucokinase and hexokinase. The following liver enzymes are most sensitive to biochemical tests: alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST). As a rule, the study is guided by the indicators of these substances.
For complete and successful monitoring of their health, everyone should know what “biochemistry analysis” is.
Areas of biochemistry research and the importance of correct interpretation of analysis results
What does biochemistry study? First of all, metabolic processes, the chemical composition of the cell, the chemical nature and function of enzymes, vitamins, acids. It is possible to evaluate blood parameters using these parameters only if the analysis is correctly interpreted. If everything is fine, then blood parameters for various parameters (glucose level, protein, blood enzymes) should not deviate from the norm. Otherwise, this should be regarded as a signal of a malfunction of the body.
Decoding biochemistry
How to decipher the numbers in the analysis results? Below are the main indicators.
Glucose
The glucose level shows the quality of the carbohydrate metabolism process. The limiting norm of content should not exceed 5.5 mmol/l. If the level is lower, this may indicate diabetes, endocrine diseases, and liver problems. Increased level glucose may be due to diabetes, physical activity, or hormonal medications.
Protein
Cholesterol
Urea
This is the name given to the end product of protein breakdown. In a healthy person, it should be completely eliminated from the body in the urine. If this does not happen, and it gets into the blood, then you should definitely check your kidney function.
Hemoglobin
This is a red blood cell protein that saturates the body's cells with oxygen. Norm: for men - 130-160 g/l, for girls - 120-150 g/l. A low level of hemoglobin in the blood is considered one of the indicators of developing anemia.
Biochemical blood test for blood enzymes (ALAT, AST, CPK, amylase)
Enzymes are responsible for full-time job liver, heart, kidneys, pancreas. Without the required amount, a complete exchange of amino acids is simply impossible.
The level of aspartate aminotransferase (AST, AST - a cellular enzyme of the heart, kidneys, liver) should not be higher than 41 and 31 units/l for men and women, respectively. Otherwise, this may indicate the development of hepatitis and heart disease.
Lipase (an enzyme that breaks down fats) plays an important role in metabolism and should not exceed 190 units/l. An elevated level indicates a malfunction of the pancreas.
It is difficult to overestimate the importance of biochemical analysis for blood enzymes. Every person who cares about their health must know what biochemistry is and what it studies.
Amylase
This enzyme is found in the pancreas and saliva. It is responsible for the breakdown of carbohydrates and their absorption. Norm - 28-100 units/l. Its high level in the blood may indicate renal failure, cholecystitis, diabetes, peritonitis.
The results of a biochemical blood test are recorded on a special form, which indicates the levels of substances. Often this analysis is prescribed as an additional one to clarify the intended diagnosis. When deciphering the results of blood biochemistry, keep in mind that they are also influenced by the patient’s gender, age and lifestyle. Now you know what biochemistry studies and how to correctly interpret its results.
How to properly prepare for donating blood for biochemistry?
Acute diseases of internal organs;
Intoxication;
Vitamin deficiency;
Inflammatory processes;
For the prevention of diseases during pregnancy;
To clarify the diagnosis.
Blood for analysis is taken early in the morning, and you cannot eat before coming to the doctor. Otherwise, the analysis results will be distorted. A biochemical study will show how correct your metabolism and salts in the body are. In addition, refrain from drinking sweet tea, coffee, or milk at least an hour or two before blood sampling.
Be sure to answer the question of what biochemistry is before taking the test. Knowing the process and its significance will help you correctly assess your health status and be competent in medical matters.
How is blood taken for biochemistry?
The procedure does not last long and is practically painless. From a person in a sitting position (sometimes they offer to lie down on the couch), the doctor takes it after applying a tourniquet. The injection site must be treated with an antiseptic. The collected sample is placed in a sterile tube and sent for analysis to the laboratory.
Quality control of biochemical research is carried out in several stages:
Preanalytical (patient preparation, analysis, transportation to the laboratory);
Analytical (processing and storage of biomaterial, dosing, reaction, result analysis);
Post-analytical (filling out a form with the result, laboratory and clinical analysis, sending to the doctor).
The quality of the biochemistry result depends on the appropriateness of the chosen research method, the competence of laboratory technicians, the accuracy of measurements, technical equipment, the purity of reagents, and adherence to diet.
Biochemistry for hair
What is biochemistry for hair? Biocurling is a method of long-term curling of curls. The difference between a regular perm and a bioperm is fundamental. In the latter case, hydrogen peroxide, ammonia, and thioglycolic acid are not used. Role active substance performs an analogue of cystine (biological protein). This is where the name of the hair styling method comes from.
The undoubted advantages are:
Gentle effect on the hair structure;
Blurred line between regrown and bio-permed hair;
The procedure can be repeated without waiting for its effect to completely disappear.
But before going to the master, you should consider the following nuances:
The biowave technology is relatively complex, and you need to be meticulous in choosing a specialist;
The effect is short-lived, about 1-4 months (especially on hair that has not been permed, dyed, or has a dense structure);
Biowave is not cheap (on average 1500-3500 rubles).
Biochemistry methods
What is biochemistry and what methods are used for research? Their choice depends on its purpose and the tasks set by the doctor. They are designed to study the biochemical structure of the cell, examine the sample for possible deviations from the norm and thus help diagnose the disease, find out the dynamics of recovery, etc.
Biochemistry is one of the most effective tests for clarifying, making a diagnosis, monitoring treatment, and determining a successful treatment regimen.
BIOCHEMISTRY. Lecture No. 1. Biochemistry as a science. Structure and functions of the main substances in the body. Subject and methods of research in biochemistry. Review of the main classes of organic substances, their role in homeostasis.
Biochemistry (from the Greek βίος - “life” and Egyptian kēme - “Earth”, also biological or physiological chemistry) - the science of the chemical composition of organisms and their components and about the chemical processes occurring in organisms. Science deals with the structure and function of substances that are components of cells and make up the body, such as proteins, carbohydrates, lipids, nucleic acids and other biomolecules. Biochemistry seeks to answer biological and biochemical questions using chemical methods.
Biochemistry is a relatively young science that arose at the intersection of biology and chemistry at the end of the 19th century. She studies the processes of development and functioning of organisms in the language of molecules, the structure and chemical processes that ensure the life of single- and multicellular creatures inhabiting the Earth. Outstanding discoveries in the field of enzymes, biochemical genetics, molecular biology and bioenergetics have turned biochemistry into a fundamental discipline that allows solving many important problems of biology and medicine.
Although there is wide range various biomolecules, many of them are polymers, i.e. complex large molecules consisting of many similar subunits, monomers. Each class of polymer biomolecules has its own set of types of these subunits. For example, proteins are polymers made of amino acids. Biochemistry studies Chemical properties important biological molecules such as proteins, particularly the chemistry of reactions catalyzed by enzymes.
In addition, most of the research in biochemistry deals with cell metabolism and its endocrine and paracrine regulation. Other areas of biochemistry include the study of the genetic code of DNA and RNA, protein biosynthesis, transport across biological membranes, and signal transduction.
The foundations of biochemistry were laid in the mid-19th century, when scientists such as Friedrich Violer and Anselm Paen were able to describe for the first time the chemical processes in living organisms and show that they are no different from ordinary chemical processes. Much work in the early 20th century led to an understanding of the structure of proteins, which became possible to carry out bio chemical reactions(alcoholic fermentation) outside the cell, etc. At the same time, the term “biochemistry” itself began to be used. The foundations of biochemistry in Ukraine were laid by Vladimir Ivanovich Vernadsky in the 20s of the last century.
Story
By the early 19th century, there was a general belief that life was not subject to the physical and chemical laws inherent in inanimate nature. It was believed that only living organisms are capable of producing molecules characteristic of them. It was only in 1828 that Friedrich Wöhler published work on the synthesis of urea, carried out in laboratory conditions, proving that organic compounds can be created artificially. This discovery dealt a serious defeat to vitalist scientists who had denied this possibility.
By that time, factual material already existed for primary biochemical generalizations, which accumulated in connection with the practical activities of people aimed at making food and wine, obtaining yarn from plants, cleaning the skin from wool with the help of microbes, studying the composition and properties of urine and other secretions healthy and sick person. After Wehler's work, such scientific concepts, like respiration, fermentation, fermentation, photosynthesis. Studying chemical composition and the properties of compounds isolated from animals and plants becomes the subject of organic chemistry (chemistry of organic compounds).
The birth of biochemistry was also marked by the discovery of the first enzyme, diastase (now known as amylase) in 1833 by Anselm Paen. The difficulties associated with obtaining enzymes from tissues and cells were used by proponents of vitalism to argue that it was impossible to study cellular enzymes outside living beings. This statement was refuted by the Russian physician M. Manasseina (1871 - 1872), who proposed the possibility of observing alcoholic fermentation in extracts of ground (i.e., lacking structural integrity) yeast. In 1896, this possibility was confirmed by the German scientist Eduard Buchner, who was able to experimentally recreate this process.
The term “biochemistry” itself was first proposed in 1882, but it is believed that it gained widespread use after the work of the German chemist Carl Neuberg in 1903. By that time, this field of research was known as physiological chemistry. After this time, biochemistry developed rapidly, especially from the mid-20th century, primarily through the development of new techniques such as chromatography, X-ray diffraction, NMR spectroscopy, radiolabeling, electron and optical microscopy, and finally molecular dynamics and other computational techniques. biology. These methods allowed the discovery and detailed analysis of many molecules and metabolic pathways of the cell, such as glycolysis and the Krebs cycle.
Other important historical event in the development of biochemistry was the discovery of genes and their role in the transmission of information in the cell. This discovery laid the possibility of the emergence not only of genetics, but also of its interdisciplinary branch at the intersection with biochemistry - molecular biology. In the 1950s, James Watson, Francis Crick, Rosalind Franklin and Maurice Wilkins were able to decipher the structure of DNA and suggested its connection with the genetic transmission of information in the cell. Also in the 1950s, George Otley and Edward Tatum proved that a single gene is responsible for the synthesis of a single protein. With the development of DNA testing techniques such as genetic fingerprinting, in 1988 Colleen Pitchfork became the first person to be charged with murder using DNA evidence, marking the first major success of biochemical forensics. In the 200s, Andrew Fire and Craig Mello showed the role of RNA interference (RNAi) in suppressing gene expression.
Currently, biochemical research is proceeding in three directions, formulated by Michael Sugar. Plant biochemistry studies the biochemistry of predominantly autotrophic organisms and studies processes such as photosynthesis and others. General biochemistry includes the study of plants, animals and humans, while medical biochemistry focuses primarily on human biochemistry and abnormalities in biochemical processes, particularly as a result of disease.
Biochemistry is a science that deals with the study of various molecules, chemical reactions and processes occurring in living cells and organisms. A thorough knowledge of biochemistry is absolutely necessary for the successful development of two main areas of biomedical sciences: 1) solving problems of preserving human health; 2) finding out the causes of various diseases and finding ways to effectively treat them.
BIOCHEMISTRY AND HEALTH
The World Health Organization (WHO) defines health as “a state of complete physical, mental and social well-being that is not merely the absence of disease or infirmity.” From a strictly biochemical point of view, an organism can be considered healthy if many thousands of reactions occurring inside cells and in the extracellular environment occur under such conditions and at such speeds that ensure maximum viability of the organism and maintain a physiologically normal (not pathological) state.
BIOCHEMISTRY, NUTRITION, PREVENTION AND TREATMENT
One of the main prerequisites for maintaining health is an optimal diet containing a number of chemicals; the main ones are vitamins, some amino acids, some fatty acids, various minerals and water. All these substances are of one kind or another of interest both for biochemistry and for the science of rational nutrition. Therefore, there is a close connection between these two sciences. In addition, it can be assumed that against the backdrop of efforts being made to contain the rise in prices for medical service, more and more attention will be paid to maintaining health and preventing disease, i.e. preventive medicine. For example, to prevent atherosclerosis and cancer, it is likely that rational nutrition will become increasingly important over time. At the same time, the concept of rational nutrition should be based on knowledge of biochemistry.
BIOCHEMISTRY AND DISEASES
All diseases are a manifestation of some changes in the properties of molecules and disturbances in the course of chemical reactions and processes. The main factors leading to the development of diseases in animals and humans are given in Table. 1.1. All of them influence one or more key chemical reactions or the structure and properties of functionally important molecules.
The contribution of biochemical research to the diagnosis and treatment of diseases is as follows.
Table 1.1. The main factors leading to the development of diseases. All of them influence various biochemical processes occurring in a cell or the whole organism.
1. Physical factors: mechanical trauma, extreme temperature, sudden changes atmospheric pressure, radiation, electric shock
2. Chemical agents and drugs: some toxic compounds, therapeutic drugs, etc.
4. Oxygen starvation: blood loss, impaired oxygen-carrying function, poisoning of oxidative enzymes
5. Genetic factors: congenital, molecular
6. Immunological reactions: anaphylaxis, autoimmune diseases
7. Nutritional imbalances: undernutrition, overnutrition
Thanks to these studies, it is possible to 1) identify the cause of the disease; 2) offer a rational and effective treatment path; 3) develop methods for mass examination of the population for the purpose of early diagnosis; 4) monitor the progress of the disease; 5) monitor the effectiveness of treatment. The Appendix describes the most important biochemical tests used to diagnose various diseases. It will be useful to refer to this Appendix whenever we are talking about the biochemical diagnosis of various diseases (for example, myocardial infarction, acute pancreatitis, etc.).
The potential of biochemistry in the prevention and treatment of disease is briefly illustrated by three examples; We'll look at some more examples later in this chapter.
1. It is well known that in order to maintain his health, a person must receive certain complex organic compounds - vitamins. In the body, vitamins are converted into more complex molecules (coenzymes), which play a key role in many reactions occurring in cells. A lack of any vitamin in the diet can lead to the development of various diseases, for example, scurvy with a lack of vitamin C or rickets with a lack of vitamin D. Determining the key role of vitamins or their biologically active derivatives has become one of the main problems that biochemists and nutritionists have solved since the beginning this century.
2. A condition known as phenylketonuria (PKU) can lead to severe mental retardation if left untreated. The biochemical nature of PKU has been known for about 30 years: the disease is caused by a deficiency or complete absence of the activity of an enzyme that catalyzes the conversion of the amino acid phenylalanine into another amino acid, tyrosine. Insufficient activity of this enzyme leads to the accumulation of excess phenylalanine and some of its metabolites, in particular ketones, in tissues, which adversely affects the development of the central nervous system. After the biochemical basis of PKU was elucidated, it was possible to find rational way Treatment: sick children are prescribed a diet low in phenylalanine. Mass screening of newborns for PKU allows, if necessary, to begin treatment immediately.
3. Cystic fibrosis is an inherited disease of the exocrine glands, and in particular the sweat glands. The cause of the disease is unknown. Cystic fibrosis is one of the most common genetic diseases in North America. It is characterized by abnormally viscous secretions that clog the pancreatic secretory ducts and bronchioles. People suffering from this disease most often die in early age from a lung infection. Since the molecular basis of the disease is unknown, only symptomatic treatment is possible. However, one can hope that in the near future, with the help of recombinant DNA technology, it will be possible to clarify the molecular nature of the disease, which will make it possible to find more effective method treatment.
FORMAL DEFINITION OF BIOCHEMISTRY
Biochemistry, as the name suggests (from the Greek bios-life), is the chemistry of life, or, more strictly, the science of chemical principles life processes.
The structural unit of living systems is the cell, so another definition can be given: biochemistry as a science studies the chemical components of living cells, as well as the reactions and processes in which they participate. According to this definition, biochemistry covers broad areas of cell biology and all of molecular biology.
TASKS OF BIOCHEMISTRY
The main task of biochemistry is to achieve a complete understanding at the molecular level of the nature of all chemical processes associated with the life of cells.
To solve this problem, it is necessary to isolate from cells the numerous compounds that are found there, determine their structure and establish their functions. As an example, we can point to numerous studies aimed at elucidating the molecular basis of muscle contraction and a number of similar processes. As a result, many compounds of varying degrees of complexity were isolated in purified form and detailed structural and functional studies were carried out. As a result, it was possible to clarify a number of aspects of the molecular basis of muscle contraction.
Another task of biochemistry is to clarify the question of the origin of life. Our understanding of this exciting process is far from comprehensive.
AREAS OF RESEARCH
The scope of biochemistry is as wide as life itself. Wherever life exists, various chemical processes occur. Biochemistry deals with the study of chemical reactions occurring in microorganisms, plants, insects, fish, birds, lower and higher mammals, and in particular in the human body. Of particular interest to students studying biomedical sciences are
the last two sections. However, it would be short-sighted to have no idea at all about the biochemical features of some other forms of life: often these features are essential for understanding various kinds of situations that are directly related to humans.
BIOCHEMISTRY AND MEDICINE
There is a broad two-way relationship between biochemistry and medicine. Thanks to biochemical research, it was possible to answer many questions related to the development of diseases, and the study of the causes and course of development of some diseases led to the creation of new areas of biochemistry.
Biochemical studies aimed at identifying the causes of diseases
In addition to those above, we will provide four more examples to illustrate the breadth of the range possible applications biochemistry. 1. Analysis of the mechanism of action of the toxin produced by the causative agent of cholera made it possible to find out important points in relation to the clinical symptoms of the disease (diarrhea, dehydration). 2. Many African plants have very low levels of one or more essential amino acids. The identification of this fact made it possible to understand why those people for whom these plants are the main source of protein suffer from protein deficiency. 3. It has been discovered that mosquitoes that carry malaria pathogens can develop biochemical systems that make them immune to insecticides; this is important to consider when developing malaria control measures. 4. Greenland Eskimos in large quantities consume fish fat, rich in some polyunsaturated fatty acids; at the same time, it is known that they are characterized by a low level of cholesterol in the blood, and therefore they are much less likely to develop atherosclerosis. These observations suggested the possibility of using polyunsaturated fatty acids to reduce cholesterol in the blood plasma.
The study of diseases contributes to the development of biochemistry
Observations of the English physician Sir Archibald Garrod back in the early 1900s. A small group of patients suffering from inborn errors of metabolism has stimulated research into the biochemical pathways that are disrupted in these conditions. Attempts to understand the nature of a genetic disease called familial hypercholesterolemia, which leads to the development of severe atherosclerosis at an early age, have contributed to the rapid accumulation of information about cellular receptors and the mechanisms of cholesterol uptake by cells. Intensive study of oncogenes in cancer cells has drawn attention to the molecular mechanisms of cell growth control.
Study of lower organisms and viruses
Valuable information, which turned out to be very useful for conducting biochemical research in the clinic, was obtained from the study of some lower organisms and viruses. For example, modern theories regulation of gene and enzyme activity was formed on the basis of pioneering studies performed on molds and bacteria. Recombinant DNA technology originated from research conducted on bacteria and bacterial viruses. The main advantage of bacteria and viruses as objects of biochemical research is high speed their reproduction; this greatly facilitates genetic analysis and genetic manipulation. Information obtained from studying viral genes responsible for the development of certain forms of cancer in animals (viral oncogenes) has made it possible to better understand the mechanism of transformation of normal human cells into cancer cells.
BIOCHEMISTRY AND OTHER BIOLOGICAL SCIENCES
The biochemistry of nucleic acids lies at the very basis of genetics; in turn, the use of genetic approaches has proven fruitful for many areas of biochemistry. Physiology, the science of how the body functions, overlaps greatly with biochemistry. Used in immunology big number biochemical methods, and in turn many immunological approaches are widely used by biochemists. Pharmacology and pharmacy are based on biochemistry and physiology; Most drugs are metabolized by appropriate enzymatic reactions. Poisons affect biochemical reactions or processes; these questions constitute the subject of toxicology. As we have already said, basically different types Pathology is a violation of a number of chemical processes. This leads to the increasingly widespread use of biochemical approaches to study various types pathologies (for example, inflammatory processes, cell damage and cancer). Many of those involved in zoology and botany make extensive use of biochemical approaches in their work. These relationships are not surprising, since, as we know, life in all its manifestations depends on a variety of biochemical reactions and processes. The barriers that previously existed between the biological sciences have been virtually destroyed, and biochemistry is increasingly becoming their common language.
