Chemotaxis

Source:  Chemotaxis    Tag:  chemotaxis neutrophil

Chemotaxis


Chemotaxis is the phenomenon in which somatic cells, bacteria, and other single-cell or multicellularglucose) by swimming towards the highest concentration of food molecules, or to flee from poisons (for example, phenol). In multicellular organisms, chemotaxis is critical to early development (e.g. movement of spermfertilization) and subsequent phases of development (e.g. migration of neurons or lymphocytes) as well as in normal function. In addition, it has been recognized that mechanisms that allow chemotaxis in animals can be subverted during cancer metastasis. organisms direct their movements according to certain chemicals in their environment. This is important for bacteria to find food (for example, towards the egg during
Chemotaxis is called positive if movement is in the direction of a higher concentration of the chemical in question, and negative if the direction is opposite.

Neutrophils are the body's first line of defense against bacterial infections. After leaving nearby blood vessels, these cells recognize chemicals produced by bacteria in a cut or scratch and migrate "toward the smell". The above neutrophils were placed in a gradient of fMLP (N-formyl-methionine-leucine-phenylalanine), a peptide chain produced by some bacteria. Although migration of cells was detected from the early days of the development of microscopy (Leeuwenhoek), erudite description of chemotaxis was first made by T W. Engelmann (1881) and W.F. Pfeffer (1884) in bacteria and H.S. Jennings (1906) in ciliates. The Nobel Prize laureate I. Metchnikoff also contributed to the study of the field with investigations of the process as an initial step of phagocytosis. The significance of chemotaxis in biology and clinical pathology was widely accepted in the 1930s. The most fundamental definitions belonging to the phenomenon were also drafted by this time. The most important aspects in quality control of chemotaxis assays were described by H. Harris in the 1950s. In the 1960s and 1970s, the revolution of modern cell biology and biochemistry provided a series of novel techniques which became available to investigate the migratory responder cells and subcellular fractions responsible for chemotactic activity. The pioneering works of J. Adler represented a significant turning point in understanding the whole process of intracellular signal transduction of bacteria.
On November 3, 2006, Dr. Dennis Bray of University of Cambridge was awarded the Microsoft Award for his work on chemotaxis on E. coli.