Why in News?

• Indian scientists have found a theoretical model explaining a unique kind of motion, called direction reversing active motion, exhibited by some bacteria.

How does a bacteria move

• Bacteria move by propelling themselves with a velocity that changes direction randomly, which is called active motion. 
• Besides bacteria, this kind of motion is found in living systems ranging from cells at the microscopic scale to the flocking of birds and fish schools at the macroscopic scale. 
• It is also seen in artificial systems, including granular matter, self-catalytic swimmers, and nano-motors.
• Some microorganisms, such as predator bacteria Myxococcus Xanthus and saprotrophic bacteria Pseudomonas putida, exhibit a unique kind of reversing active motion, whereby, in addition to a diffusive change of direction, the motion also completely reverses its direction intermittently.

The uses

• This analysis can help in building more efficient artificial micro- and nano-motors used in drug delivery and bio-imaging using the concept to incorporate a reverse gear.

 Reference:

1. https://www.thehindu.com/sci-tech/science/scientists-decipher-how-some-bacteria-can-operate-a-reverse-gear/article35653078.ece