Please answer the following question 1 Describe the mechanis

Please answer the following question!

1. Describe the mechanism by which chemotactic bacteria respond to gradients of attractants and repellents in liquid. Include all important details.

I need this to be detailed and explained as if someone wanted to know. Please keep the answer in between 150-200 words!

Solution

Chemotaxis is the ability of bacteria to respond to chemical stimuli in the environment. It allows bacteria to respond to and follow nutrient gradients and / or other environmental stimuli. Chemotaxis is a specific response of the bacteria to the presence of attractants in the environment. When bacteria sense a positive gradient, they tumble less frequently than the normal. Bacteria which sense a negative temporal gradient tumble more than the normal. Each tumble disorients the bacteria and it starts to move in a new direction.

Bacteria have chemotactic receptors located in the outer membrane which are responsive to different levels of a particular substance. When the attractant molecules present in the environment bind to the sensory molecules, the sensory molecules undergo a change in conformation. This response is transmitted to the flagellar motor. As a result the bacteria is able to run to the chemoattractant for a longer duration of time. Bacterial chemotaxis depends on the control of flagellar rotation which is done by a signal transduction system involving a protein CheY. The Che Y protein acts like a shuttle between the receptor complexes and the flagellar motor complexes.