Scavenging Reactive Species

Biological Strategy

Rotifers

AskNature Team

Image: VojtaMaur / Shutterstock / Some rights reserved

Protect From Nuclear Radiation

Nuclear radiation is a threat that some living systems can survive. Most survival strategies help living systems survive other kinds of extreme threats, although in situations where there has been human-caused exposure to nuclear radiation, some quickly reproducing organisms (such as bacteria) might develop new strategies. The tardigrade (also called a water bear) survives extreme conditions by undergoing a suspended metabolic state called cryptobiosis. Going into this state helps it survive nuclear radiation, dehydration, and low temperatures.

Search this Function

Modify Free Radical Reactivity

Free radicals are molecules react very easily with other molecules, which can cause them to breakdown or cease to function in the same way. They are natural by-products of many biochemical reactions in the body, including metabolism and immune responses. Different organisms have adapted to modify or control free radical activity, in order to maintain the integrity of their biochemical processes and improve their fitness.

Search this Function

Animals

Kingdom Animalia (“having breath or soul”): Mammals, reptiles, sponges, corals, insects, birds

This kingdom captures a staggering variety of life—from the smallest coral polyp to the largest elephant. Although animal body shapes and life histories vary, there are a few defining characteristics. Animals are heterotrophs, meaning they gain energy from eating other organisms, and have developed from single-celled ancestors to highly diversified and coordinated multicellular forms. Unlike plant and fungi cells that have rigid cell walls, animal cells are bound by more flexible combinations of proteins. Most animals have cells organized into tissues and are able to move within their environment.

Search this Living System

Bdelloid rotifers are resistant to ionizing radiation due to enhanced capacity for scavenging destructive radiation-induced molecules before they have a chance to cause damage.

Ionizing radiation, including that from nuclear materials and X-rays, can damage DNA and proteins directly by forming or breaking bonds in DNA or indirectly by the formation of reactive oxygen species (ROS). ROS, such as free radicals and peroxides, can destroy proteins. D. [Deinoccocus] radiodurans and bdelloid rotifers are able to survive exposure to ionizing radiation because they are able to scavenge ROS before they can wreak havoc, thereby leaving proteins charged with repairing damaged DNA to do their job.

Image: Ian Sutton /

Last Updated August 23, 2016

References

Journal article

Extreme resistance of bdelloid rotifers to ionizing radiation

Proceedings of the National Academy of Sciences | 25/03/2008 | E. Gladyshev, M. Meselson

embedly preview

Reference

Journal article

A new perspective on radiation resistance based on Deinococcus radiodurans

Nature Reviews Microbiology | 27/01/2009 | Michael J. Daly

embedly preview

AskNature