Flavobacterium Sp K172
Todd Jaco

Most microbial pathways have existed for a very long time, many since the existence of the very first microbe.  Fermentation, substrate-level phosphorylation, and oxidization of complex sugars are just a few of the common processes that occur daily inside of countless microbes.  These processes, and their associated enzymes, have been found proceeding inside of many samples of bacteria.  However, there are rare cases when traditional processes are altered or even completely rearranged.  Even more rare, such as in the case of F. Sp. K172, unique biological processes are sometimes found.

It is important to understand the common occurrences of Flavobacterium before discussing the uniqueness of Sp. K172Flavobacterium is a genus of bacilli bacteria that are gram-negative.  These bacteria tend to live in fresh water sources, but are quite common in many types of damp soil as well.  Species of Flavobacterium often cause disease in fish living in the same water source.  Most Flavobacterium produce very similar enzymes and follow equally similar metabolic pathways.

Flavobacterium Sp. K172 is a unique bacterium that has not yet received an official name, though it is often called the “nylon eating bacteria”.  Sp. K172 was found in 1975 in Japan by a team of scientists who were researching the drainage ponds of a nylon production facility.  This bacterium was found to have the ability to digest byproducts of the nylon 6 production process.  Lab tests showed that the bacterium made use of three enzymes to break down and digest nylon byproducts such as 6-aminohexanoate.  Though Sp. K172 was identified as a Flavobacterium, the three enzymes it employed were very different from enzymes used in any of the other Flavobacterium species.  In fact, that this bacterium could produce these enzymes at all was astounding, since these nylon byproducts had not been known to exist before the invention of the nylon 6 production method in 1935.

Though Flavobacterium Sp. K172 uses the nylon 6 byproducts as its sole source of carbon in nature, it has shown exceptional adaptability in the lab.  The bacterium has been repeatedly modified to produce enzymes more akin to the traditional Flavobacterium digestion enzymes, curing it of its dependency on nylon as a source of carbon.  Though this helps support that Sp. K172 is a Flavobacterium, it does little to explain how this metabolic pathway developed so quickly.  Though this is not an unheard of rate, it was still a very rapid development.  As well, the enzymes are very dissimilar to what the original bacteria that became Flavobacterium Sp. K172 probably had been producing at the time prior to their introduction to the nylon 6 byproducts.  Since Flavobacterium Sp. K172 has yet to have been located in any other place on the globe, it is currently speculated that this was a terribly effective random mutation.  Random mutations of this magnitude are not impossible, and some have even been recorded and even induced.  A natural mutation this quickly and with this drastic and impressive of results, however, is rare indeed.  Flavobacterium Sp. K172 raises many questions as to the adaptability of microbiological life forms, and will continue to be an interesting specimen for the foreseeable future.


T. Hatozaki, S. Kinoshita, A. Nakata, S. Negoro, H. Okada, H. Shinagawa. “Plasmid Control of 6-Aminohexanoic Acid Cyclic Dimer Degradation Enzymes of Flavobacterium sp. K172.” Journal of Bacteriology, 2010.

“Insertion sequence IS6100 on plasmid pOAD2, which degrades nylon oligomers.” Journal of Bacteriology, 2010. February, 1994. <PubMed.gov/>

Wikipedia contributors. "Nylon-eating bacteria." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 28 Jan. 2010. Web. 17 Feb. 2010.

*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.


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