Desulfofrigidus oceanense
Katie Mae Herrington

There are many secrets that make microorganisms successful in this world, and one of those secrets is their ability to survive.  Desulfofrigus oceanense is a psychrophile, which means it has the ability to survive extremely frigid temperatures, often ranging from 0 to 15 degrees Celsius.  D. oceanense was first discovered in 1999 by Christian Knoblauch off the coast of Svalbard, an archipelago located halfway between Norway and the North Pole.  Five different Desulfofrigus specimen were isolated:  Desulfofrigus oceanense, Desulfofrigus fragile, Desulfofaba gelida, Desulfotalea psychropila, and Desulfotale arctica.  D. oceanense, along with the other four specimens discovered, use the most common fermentation products from their marine surroundings, like acetate, propionate, and hydrogen, as an energy source.

D. oceanense possess special proteins that contain enzymes that continue to function at the extreme temperatures of the Arctic Circle.  Enzymes in most organisms will either denature or refuse to work if asked to function in extreme temperatures, while D. oceanense  keeps chugging away, functioning at full speed without any types of glitches.  Microbiologists believe this is because the enzyme structure of D. oceanense is a much looser structure then normal enzymes, meaning D. oceanense enzymes lack a few fastener molecules that keep typical enzymes rigid.  The flexible enzyme structure allows for energy conservation, which comes in handy considering the frosty atmospheres they have chosen to reside in.  This ability to survive in the extreme cold is not only important to D. oceanense, but also many members of its ecosystem.  Fish in the areas surrounding Svalbard have been discovered to contain forms of these psychrophiles, leading microbiologists to believe that the fish are taking advantage of D. oceanense sturdy proteins, and using them for themselves as well.

D. oceanense also has another trick up its sleeve when it comes to survival, a simple yet genius tactic.  D. oceanense keeps its membrane fluid by inserting extra fatty acids into the membrane, which allows for continued movement of food into the cell and waste products out of the cell.  In some psychrophiles the fatty acids are polyunsaturated fatty acids, which are seldom found in prokaryotes.

Not much is known about Desulfofrigus oceanense yet, because it is still young in its discovery.  But with time, microbiologists will discover more of its hidden secrets.

References

http://www.microbeworld.org/know/cold.aspx
http://resources.metapress.com/pdf-preview.axd?code=l59307618p87141q&size=largesthttp://www.ebi.ac.uk/2can/genomes/bacteria/Desulfotalea_psychrophila.html

*Disclaimer - This report was written by a student participaring in a microbiology course at the Missouri University of Science and Technology. The accuracy of the contents of this report is not guaranteed and it is recommended that you seek additional sources of information to verify the contents.

 

Return to Missouri S&T Microbiology HomePage Go to DJW's HomePage