How gonorrhea ensures its survival

A U.S. research team has discovered the secret of gonorrhea: The bacteria exchange genetic material with pieces from its human host and are extremely adaptable.
The gonorrhea as the clap is officially called, is one of the most common sexually transmitted diseases in the world: According to the World Health Organisation (WHO) are infected each year about 60 million people over sexual contact with the bacterium Neisseria gonorrhoeae - also known as gonorrhea. The untreated gonorrhea can lead to a joint in both sexes and endocardium ignition and also infertility in women. It is one of the few diseases that are found exclusively among men. Exactly this feature inspired the researchers to Hank Seifert from Northwestern University in Chicago to investigate what the bacteria is doing in this economy so successful. To this end they deciphered genetic pieces of 14 Neisseria colonies derived from gonorrhea patients. Results: Three variants of the isolated bacteria contained DNA fragments that were identical to a DNA fragment of the human genome.



That was the first known evidence that gene transfer from bacteria to humans is possible, scientists say. This exchange gives the microbes could have an evolutionary advantage, enabling them, have so successfully adapted to the human host, reports the Fort shearing team in the online journal "mBio.


Adaptable thanks to gene exchange

"This discovery not only gives us an insight into the evolution, but also a reference to establish how the bacteria to adapt constantly to survive in their host," says study leader Hank Seifert. Whether the currently discovered gene transfer actually took an advantage for the bacteria and if so, what the researchers know, however, not yet. Yet they keep their discovery to be important: Although it is been known that bacteria can exchange genetic material with each other and with yeast. An indication of gene exchange between bacteria and humans have so far not given.

Hank Seifert and his colleagues also combed through the genome of the closely related meningococcal, known in technical language Neisseria meningitidis as a - cause of bacteria meningitis. in spite of the strong genetic relationship between the two microorganisms in the meningitis bacteria no traces of human DNA, the researchers report. Therefore have the first case of gene transfer between gonococci and its human host probably occurred before not too long ago, the researchers concluded. Next they want to determine the function of the replaced piece of DNA in more detail.