Bacteria of extreme longevity – myth or reality?

 RIs 1 
Bacteria in ancient permafrost, photo by V.Rogov

It is known that bacteria in our bodies protect our health. Microorganisms inhabit different sites of the human body. The human gut is place to a huge number of microorganisms, about 100 trillion bacterial cells belonging to 1,000 species or more. A certain set of microorganisms are common to every person. Bacteria in permafrost as well as in other severe environment are distinguished by special properties, including antibiotic resistance, extreme resistance and longevity, and what could be their role in human health? And, is it true the bacteria is able to live thousands of years?

There are a few important things which have to be taken into account:

  1. Bacteria is aging as well as other living things. Aging occurs even in resistant Antrax bacteria. Although biological immortality is discussed, single cells are subject of senescence.
  2. Alive bacteria have been found in Antarctic and other ice, amber, ancient salts and permafrost. Age of the material varied from a few thousand to hundreds of millions of years.
  3. If the bacteria is able to live for such a long time how the bacterial cells protect themselves against damaging agents destroying human and all other living bodies? DNA damage response in living cells is important for their survival.
  4. Is there any chance they can teach us how to live longer?

Aging in bacteria has similar features as in other organisms. Ancient DNA is subject to decay. DNA degradation in permafrost has been studied. Therefore cells buried in ancient permafrost or salts should resist damages. Number of findings of bacteria in millions years old amber, salts and permafrost is raising. Thus, the living microorganisms in permafrost or other ancient material apparently have special mechanisms of repair of cell structures, necessary for their survival. Ancient bacteria show evidence of DNA repairParadoxical DNA repair and peroxide resistance gene conservation in Bacillus have been also shown. The bacteria from ancient environments may have the key to a life lasting for thousands of years.

The question do these ancient bacteria exist is still under discussion. Geologically ancient DNA is a fact or artefact? The mechanism which keeps the buried bacteria alive obliviously is extremely strong. It has been found a curiously modern DNA for a 250 million-year-old bacterium. It is interesting that permafrost bacteria has the same. Molecular evolution leads to diversity in bacterial world. If the rate of the molecular evolution remains constant, then the bacteria should not have the modern genome. However, the bacteria probably keeps its genome stable, some signs of extremely low level evolution were found in the modern environment, and that may probably explain the results.

The bacteria could be useful. For example, bacterial DNA prolongs the survival of inflamed cells. Immunostimulatory ability of Bacillus could have a practical applications. A probiotic activity of a bacterial stain from ancient permafrost has been noticed as well as its physiological effects, and some bacteria may probably have even anti-tumor properties what should be studied.

Bacteria in permafrost – their nature and implications in medicine: Conjoined International Conference of Department of Geocryology of MSU and International Union for Difficult-to-treat-Diseases