Biochemistry Introduction PDF

BIOCHEMISTRY. Introduction — Biochemistry is the systematic study of the chemicals of living systems, their organization, and their participation in the processes of life. — It is a field in which new discoveries are made almost daily about how cells manufacture the molecules needed for life...

BIOCHEMISTRY. Introduction — Biochemistry is the systematic study of the chemicals of living systems, their organization, and their participation in the processes of life. — It is a field in which new discoveries are made almost daily about how cells manufacture the molecules needed for life and how the chemical reactions by which life is maintained — It seeks to describe the structure, organization and functions of living matter in molecular terms Three Principal areas of Biochemistry 1. Structural chemistry 2. Study of metabolism 3. Molecular genetics  Three Principal areas of Biochemistry 1. Structural chemistry - components of living matter and the relationship of biological function to chemical structure. 2. Study of metabolism – the totality of chemical reaction that occur in living matter  Metabolism - is a collection of chemical reactions that takes place in the body’s cells. - converts the fuel in the food we eat into the energy needed to power everything we do, from moving to thinking to growing. 3. Molecular genetics – a field that seeks to understand heredity and the expression of genetic information in molecular terms.  Biochemistry as a Discipline and Interdisciplinary Science — From Organic chemistry - which describes the properties of biomolecules — From medical research – which increasingly seeks to understand diseases stated in molecular terms — From nutrition – which has illuminated metabolism by describing the dietary requirements for maintenance of health  From Microbiology – which that single-celled organisms and viruses were ideally suited for the clarification of many metabolic pathway From Physiology – which provides understanding of life processes at the cell and tissue levels and thereby opened doors for molecular investigations From cell biology – which describes the biochemical division of labor within the cell — From biophysics – which uses the techniques of physics to help understand life at the molecular level. — From genetics – which describes mechanisms that give a particular cell or organism in its biochemical identity.. Developement of Biochemistry — The history of Biochemistry spans approximately 400 years. Although the term “biochemistry” seems to have been first used in 1882, it is generally accepted that the word “biochemistry” was first proposed in 1903 by Carl Neuberg, a German Chemist. — 1828, Friedrich Wohler synthesized urea from inorganic compound using ammonium cyanate, proving that organic compounds can be created artificially. This was followed by chemical studies of respiration, fermentation and the qualitative analysis of naturally occurring substances.  In 1878 German physiologist Wilhelm Kuhne (1837-1900) coined the term enzyme which comes from Greek word “in leaven” to describe this process. The word enzyme was used later to refer to non living substances such as pepsin and the word ferment used to refer to chemical activity prodced by living organisms. — In 1897 – Eduard Buchner began to study the ability of yeast extracts to ferment sugar despite the absence of living yeast cells, until a series of experiment, he found out that the sugar can be fermented even when there were no living yeast cells in the mixture. — In 1926 – James B. Sumner showed that the enzyme urease, was a pure protein and crystallized it like any other organic compound and did likewise for the enzyme catalase in 1937. — Since then, Biochemistry has advanced especially since the mid-20th century, with the development of new techniques such as chromatography, X-ray diffraction, NMR spectroscopy, radio isotopic labeling, electron microscopy and molecular dynamics simulations —. These techniques allowed for the discovery and detailed analysis of many molecules and metabolic pathway of the cell, such as glycolysis and the Krebs cycle (citric acid cycle), and was contributed by Hans Krebs, who made huge contributions to the study of metabolism. In addition, he and Hans Kornberg discovered the urea cycle, citric acid cycle and the glycoxylate cycle. — Avery, MacLeod and McCarty (1944) show DNA to be the agent of genetic transformation. — — Today, the findings of Biochemistry are used in many areas from genetics to molecular biology and from agriculture to medicine