Bacterial Chemotaxis

Bacterial Chemotaxis consists of the ability of bacteria cells, somatic cells, and single and multi-cellular organisms which move in a particular direction in response to the chemical stimuli that are used for finding food or running away from harmful substances. Positive chemotaxis is the movement of the organism which occurs in the direction of higher concentration in the direction of the attractant whereas negative chemotaxis is the movement that occurs in the opposite direction.

What is Bacterial Chemotaxis?

The movement that occurs in an organism in response to the stimuli where the bacterial cells, somatic cells, and single and multicellular organisms direct the movement of the organism which is according to the chemicals present in the environment is known as Bacterial Chemotaxis. One of the main features of chemotaxis is the motility of sperm. In eukaryotic cells, it is used in the development, growth, and functioning.

Discovery of Bacterial Chemotaxis.

The discovery of bacterial chemotaxis was first discovered by T.W. Engelmann in 1881 and W. F. Pleffer in 1884 in the bacteria and in the ciliates in 1906 it was discovered by H. S Jennings. The important aspects in quality control of chemotaxis assays was briefly described in 1950s by H. Harris.

Features of Bacterial Chemotaxis

Some of the features of Bacterial chemotaxis are mentioned below:

• When the bacterial chemotaxis rotates in the counterclockwise direction it further result in the alignment of the flagella into the rotating bundle which causes the cells to move in straight forward motion.
• The tumbling motions in the flagella is caused due to the clockwise rotation which result in the breaking of flagella bundle in a manner such that the ends of the flagellum which is pointed in different directions.

Types of Bacterial Chemotaxis

There are two types of bacterial chemotaxis are as follows:

• Positive chemotaxis – The movement which is towards higher concentration of diffusible substances (towards an attractant) is known as positive chemotaxis. For Example- brucei engaging in SoMo shows positive chemotaxis towards Escherichia coli.
• Negative chemotaxis – The movement which is in the negative direction (away from a repellent). It arises to avoid places with higher level of toxins is known as negative chemotaxis. Example- Urease-coated liposomes.

Signal Transduction Process in Chemotaxis

CheA and CheW are the present proteins which are mainly responsible for binding themselves to the receptor. The activation of receptor is due to the presence of external stimuli which causes in the process of autophosphorylation which takes place in the histidine kinase, the CheA. This kinase further transfers to the phosphoryl groups which are produced into the conserved residues as a response to the action of proteins CheB and CheY. The most important thing is CheA is a histidine and doesn’t cause transfer of phosphoryl group whereas the CheB is the response regulator which takes place from the group from CheA. The signal transduction process is known as two component system.

Importance of Chemotaxis in Environment

Chemotaxis allows bacteria to find that environment provides them greatest supply of energy. It plays an important role in physiological events such as wound healing, tissue morphogenesis and axon guidance. It is a mechanism in which the bacteria effectively respond to the changes in the chemical composition of their environment by chemically approaching favorable environment and by avoiding the unfavorable environments.

Applications in Biotechnology

Bacterial chemotaxis plays a major role in biotechnology such as bacterial cells use to produce biofuels such as biodiesel and ethanol. These biofuels are renewable and consists of traditional fossil fuels. In biological processes chemotaxis is used in the biofilm formation, bacterial pathogenesis, host infection and quorum sensing. It is applied in drug delivery, horizontal gene transfer, bioremediation.

FAQs on Bacterial Chemotaxis

1. What do you Mean by Bacterial Chemotaxis?

Answer:

It refers to the ability of bacteria cells, somatic cells, single and multi cellular organisms which move in a particular direction in response to the chemical stimuli.

2. Name the types of Single-Celled Organism of Bacterial Chemotaxis ?

Answer:

The two types of single-celled organism of bacterial chemotaxis are as follows:

• amoeboid migration
• mesenchymal migration.

3. Name the Types of multi-celled Organism of Bacterial Chemotaxis ?

Answer:

The two types of multi-celled organism of bacterial chemotaxis are as follows:

• Collective migration
• Cell streaming

4. How Bacterial Chemotaxis move in Straight Forward Motion ?

Answer:

When the bacterial chemotaxis rotates in the counterclockwise direction it further result in the alignment of the flagella into the rotating bundle which causes the cells to move in straight forward motion.