chemotaxis

Examples of chemotaxis in the following topics:

• Chemotaxis

  • Chemotaxis is the phenomenon whereby bacterial cells direct their movements according to certain chemicals in their environment.
  • Positive chemotaxis occurs if the movement is toward a higher concentration of the chemical in question.
  • Conversely, negative chemotaxis occurs if the movement is in the opposite direction.
  • Chemoattractants and chemorepellents are inorganic or organic substances possessing chemotaxis-inducer effect in motile cells .
  • Their method of chemotaxis is different.

• Cytokines and Chemokines

  • Their name is derived from their ability to induce directed chemotaxis in nearby responsive cells; they are chemotactic cytokines .

• Movement and Migration

  • This movement can be in response to light (phototaxis), chemical signals (chemotaxis), or gravity (geotaxis).
  • An example of a positive chemotaxis is exhibited by the unicellular protozoan Tetrahymena thermophila.

• Morphologically Unusual Proteobacteria

  • One daughter is a mobile "swarmer" cell that has a single flagellum at one cell pole that provides swimming motility for chemotaxis.
  • One daughter is a mobile "swarmer" cell that has a single flagellum at one cell pole that provides swimming motility for chemotaxis.

• Types of Cytokines Participating in Immune Response

  • Chemokines are protein cytokines that are mainly involved in facilitating chemotaxis (chemical-stimulated movement) in immune cells.
  • This category also includes cytokines that are only involved in leukocyte migration, such as CCL2 which causes monocyte chemotaxis and stimulates its differentiation into macrophages inside of tissues.

• Antimicrobial Peptides

  • AMPs have been shown to be important in such diverse functions as angiogenesis, wound healing, cytokine release, chemotaxis, and regulation of the adaptive immune system.

• Macrophages

  • To enter a tissue, the monocyte in peripheral blood must adhere to the vessel wall, cross the endothelial cell barrier, and then migrate towards the stimulus; a process known as chemotaxis.

• Vascular Spasm

  • During inflammation, vasodilation occur, along with increased vascular permeability and leukocyte chemotaxis, ending the spasm of vasoconstriction and hemostasis as wound healing begins.

• Cell Migration in Multicellular Organisms

  • The amoeba Dictyostelium discoideum is useful to researchers because they consistently exhibit chemotaxis in response to cyclic AMP; they move more quickly than cultured mammalian cells; and they have a haploid genome that simplifies the process of connecting a particular gene product with its effect on cellular behavior.

• Phagocyte Migration and Phagocytosis

  • Chemotaxis is the process by which phagocytes follow the cytokine "scent" to the infected spot.