For the last century, the medical community has largely assumed that the bacteria that inhabit our bodies and natural surroundings have been accurately characterized and documented.

Yet according to Penn State researcher Jennifer Loveland-Curtze, “Microbes comprise up to one-third or more of the Earth’s biomass, yet fewer than 8,000 microbes have been described out of the approximately 3,000,000 that are presumed to exist,”

The statistic may be mind-boggling to some, yet, in reality, should come as no surprise. Considering the fact that bacteria are notoriously adept at evolving crafty survival mechanisms and have had eons in which to do so, the amount of research over the previous decades aimed at characterizing new bacteria and their survival adaptations has actually been minimal.

This week, one more of the potential 3,000,000 bacterial species that inhabit our planet was discovered by Loveland-Curtze and team, who released the results of a study in which they document the discovery of a new ultra-small species of bacteria that has survived for more than 120,000 years within the ice of a Greenland glacier at a depth of nearly two miles. The microorganism’s ability to persist in this low-temperature, high-pressure, reduced-oxygen and nutrient-poor habitat makes it particularly useful for studying how life, in general, can survive in a variety of extreme environments on Earth and possibly elsewhere in the solar system.

Called Chryseobacterium greenlandensis, the organism is one of only about 10 scientifically described new species originating from polar ice and glaciers. To study the bacterium in the laboratory, the research team filtered the cells from melted ice and incubated them in the cold in low-nutrient, oxygen-free solutions. The scientists then characterized the genetic, physiological, biochemical and structural features of the species. According to the team, the ultra-small size of the new species could be one explanation for why it was able to survive for so long in the Greenland glacier.

Thus, like many L-forms, Chryseobacterium is among the ubiquitous and tiny bacterial which, because of their minuscule size, are able to pass through microbiological filters. They have even been found living in the ultra-purified water used for dialysis. “Ultra-small cells could be unknown contaminants in media and medical solutions that are thought to have been sterilized using filters,” said Loveland-Curtze.

“Filterable forms” of bacteria have been known for a century — these are the kind of bacteria involved in cancer and certain other inflammatory diseases, states retired Kaiser-Permanente clinician Alan Cantwell. “One suspects these buggers are in vaccines and also in “sterile solutions.”

And so another bacterium joins the list of pathogens previously unknown to man, pathogens that have evolved to survive under the most challenging of circumstances. It’s discovery serves as a stark reminder of the number of chronic pathogens yet to be detected in the human body, many or most of which contribute to inflammatory disease. After all, if bacteria can proliferate in the depths of a glacier, it’s no wonder they have evolved so many ingenious ways to remain alive inside our myriad tissues and cell types.

In fact, the hardiness of Chryseobacterium brings to mind the recent study by researchers at the Glasgow Infection and Immunity Group who used molecular technology to sequence the bacteria present on the surface of prosthetic hip joints. The team discovered that some of their human subjects harbored bacteria previously considered capable of surviving only on hydrothermal heat vents. The fact that such bacteria can clearly remain alive despite the process of boiling or other high-temperature treatments should serve as another eye opener to those who underestimate the capability of bacteria to survive in the human body.