Biochemical:Relating tobiochemistry, the application of the tools and concepts of chemistry to living systems.
Biochemists study such things as the structures and physical properties of biological molecules, includingproteins,carbohydrates,脂质, andnucleic acids; the mechanisms ofenzymeaction; the chemical regulation ofmetabolism; the chemistry of nutrition; the molecular basis ofgenetics(inheritance); the chemistry of vitamins; energy utilizationinthecell; and the chemistry of theimmune response.
Fields closely related to biochemistry include biophysics, cell biology, andmolecular biology. Biophysics applies to biology the techniques of physics. Cell biology is concerned with the organization and functioning of the individual cell. Molecular biology, a term first used in 1950, It overlaps biochemistry and is principally concerned with the molecular level of organization.
Thescienceof biochemistry has also been called physiological chemistry andbiological chemistry.
History:
Modern chemistry: Antoine-Laurent Lavoisier (1743-1794), thefatherof modern chemistry, carried out fundamental studies on chemical oxidation and showed the similarity between chemical oxidation and therespiratoryprocess.
Organicchemistry: In the 19th century, Justus von Liebig studied chemistry in Paris and carried the inspiration gained by contact with the former students and colleagues of Lavoisier back to Germany where he put organic chemistry on a firm footing.
Enzymes: Louis Pasteur proved that various yeasts andbacteriawere responsible for "ferments," substances that caused fermentation and, in some cases,disease. He also demonstrated the usefulness of chemical methods in studying these tiny organisms and was the founder of what came to be calledbacteriology. Later, in 1877 Pasteur's ferments were designated as enzymes.
Proteins: The chemicalnatureof enzymes remained obscure until 1926,when the first pure crystalline enzyme (urease) was isolated. This enzyme and all others proved to be proteins, which had already been recognized as high-molecular-weight chains ofamino acidswhich we now know are the building blocks ofprotein.
Vitamins: The mystery of how minute amounts of dietary substances prevent diseases such asberiberi,scurvy, andpellagracame clear in 1935 when riboflavin (vitamin B2) was found to be an integral part of an enzyme.
ATP: In 1929 thesubstanceadenosine triphosphate(ATP) was isolated frommuscle. The production of ATP was found associated with respiratory (oxidative) processes in the cell and in 1940 ATP was recognized by F.A. Lipmann as the common form of energy exchange in cells.
Radioisotopes: The use of放射性isotopes of chemical elements to trace the pathway of substances in the body was initiated in 1935 by R. Schoenheimer and D. Rittenberg, providing an important tool for investigating the chemical changes that occur in cells.
DNA: In 1869 a substance was isolated from thenucleiofpuscells and was callednucleic acid, which later proved to bedeoxyribonucleic acid(DNA). It was not until 1944 that the significance of DNA asgeneticmaterial was revealed, whenbacterialDNA was shown to change the genetic matter of other bacterial cells. Within a decade, thedouble helixstructure of DNA was proposed byWatsonandCrick, providing an understanding of how DNA functions as the genetic material.
