Biochemistry





Biochemistry is the study of the chemical reactions and interactions that
take place in living organisms, especially the structure and function of
their components, such as proteins, carbohydrates, lipids, nucleic acids,
and small molecules present in cells.

Biochemistry could also (now) be defined as being the chemistry of
enzyme-mediated reactions, whether in vivo or in the test tube, with natural
or artificially modified enzymes and other chemicals.

Development of biochemistry

The dawn of biochemistry may have been the discovery of the first enzyme,
diastase, in 1833 by Anselme Payen. In 1828, Friedrich Wšhler published a
paper about the synthesis of urea, proving that organic compounds can be
created artificially, in contrast to the common belief of the time that
organic compounds can only be made by living organisms. Since then,
biochemistry has advanced, especially since the mid-20th century, with the
development of new techniques such as chromatography, X-ray diffraction,
NMR, radioisotopic labelling, electron microscopy and molecular dynamics
simulations. These techniques allowed for the discovery and detailed
analysis of many molecules and metabolic pathways of the cell, such as
glycolysis and the Krebs cycle.

Today, the findings of biochemistry are used in many areas, from genetics to
molecular biology and from agriculture to medicine. The first application of
biochemistry was probably the making of bread using yeast, about 5000 years ago.

Categories

Biochemistry is principally concerned with the chemistry of substances that
can be classified into a few major categories:

   * Carbohydrates
   * Lipids
   * Proteins and Amino acids
   * Nucleic acids

The bulk of biochemical investigation focuses on the properties of proteins,
many of which are enzymes. For historical reasons, the biochemistry of
metabolism has been one of the most extensively described aspect of the
cell. Important modern-day areas include the genetic code (DNA, RNA),
protein synthesis, cell membrane transport, signal transduction and energy
decomposition cycles.