<italic>Haemophilus influenzae</italic> is among the smallest bacteria: 0.2–0.3 by 0.5–2.0 μm, which is about the smallest object that can be seen through a light microscope. The statement is no longer true! In the recent Science issue (22nd December 2006), Baker <italic>et al.</italic><xref ref-type="bibr" rid="bib001">1</xref> have reported the discovery of a novel microbial species whose members are extremely small, the so called ARMAN (Archaeal Richmond Mine Acidophilic Nanoorganism). The latter have been isolated from the Richmond Mine, California. Before closing in 1963, the mine produced gold, silver, iron and copper. Over the years, rains and surface water ran over the exposed minerals producing sulphuric acid. The team that reported the novel microbial species was led by Brett J. Baker and Jillian F. Banfield of the Department of Earth and Planetary Sciences, University of California, Berkley, USA. The nanoorganisms can even thrive in water drainage as acidic as battery acid, and loaded with toxic metals zinc, iron, copper and arsenic. As it was difficult to isolate them by routine techniques or to detect them by PCR-based survey, Banfield and her colleagues<xref ref-type="bibr" rid="bib002">2</xref> employed shotgun sequencing to pick out the bacteria from the mine slime. It is the first successful example of community genomic analysis to profile the organisms in a drop of scummy water. Their work makes it clear that shotgun sequencing can also pick out rare organisms, too small to be seen easily, and too novel to be isolated by other genetic techniques<xref ref-type="bibr" rid="bib001">1</xref>,<xref ref-type="bibr" rid="bib002">2</xref>.The nanoorganisms as they called them fall within a large class of microbes known as thermophiles, which are Archaea that live in warm and even scalding conditions.The nanoorganisms picked up were extremely small, around 200 nm in diameter. These microbes though reported to be among the smallest cellular life forms, have not been cultured yet. It is also to be seen whether they have enough genes to be capable of independent existence or they are symbiotic or are parasitic.Only further detailed scientific studies will prove that these organisms are the smallest to be ever found and that they can reproduce. If this turns out to be correct we might need to reconsider existing paradigm for minimum requirements for life. The authors further noted that this community of microbes is relevant to generate potential probing strategies for life on other planets, especially on Mars. It may thus influence the search for microscopic life forms elsewhere in the solar system a discovery that will prove that life is not unique to earth.</sec></body><back><ref-list><title>References

IJM

Indian Journal of Microbiology

0046-8991

The Association of Microbiologists of India

ijm-46-4-016

RESEARCH ARTICLE

Nanoorganisms: Smallest form of life got smaller!

Lal

Rup

*Jit

Simran

Verma

Mansi

Dadhwal

Mandeep

Singh

Ajaib

Prakash

Sharma

Poonam

Khanna

Manisha

Department of Zoology, University of Delhi, Delhi-110007.

*E-mail: ijmami@gmail.com, Tel: 91 11 27666254.

122006

464413413

<italic>Haemophilus influenzae</italic> is among the smallest bacteria: 0.2–0.3 by 0.5–2.0 μm, which is about the smallest object that can be seen through a light microscope. The statement is no longer true! In the recent Science issue (22nd December 2006), Baker <italic>et al.</italic><xref ref-type="bibr" rid="bib001">1</xref> have reported the discovery of a novel microbial species whose members are extremely small, the so called ARMAN (Archaeal Richmond Mine Acidophilic Nanoorganism). The latter have been isolated from the Richmond Mine, California. Before closing in 1963, the mine produced gold, silver, iron and copper. Over the years, rains and surface water ran over the exposed minerals producing sulphuric acid. The team that reported the novel microbial species was led by Brett J. Baker and Jillian F. Banfield of the Department of Earth and Planetary Sciences, University of California, Berkley, USA. The nanoorganisms can even thrive in water drainage as acidic as battery acid, and loaded with toxic metals zinc, iron, copper and arsenic. As it was difficult to isolate them by routine techniques or to detect them by PCR-based survey, Banfield and her colleagues<xref ref-type="bibr" rid="bib002">2</xref> employed shotgun sequencing to pick out the bacteria from the mine slime. It is the first successful example of community genomic analysis to profile the organisms in a drop of scummy water. Their work makes it clear that shotgun sequencing can also pick out rare organisms, too small to be seen easily, and too novel to be isolated by other genetic techniques<xref ref-type="bibr" rid="bib001">1</xref>,<xref ref-type="bibr" rid="bib002">2</xref>.The nanoorganisms as they called them fall within a large class of microbes known as thermophiles, which are Archaea that live in warm and even scalding conditions.The nanoorganisms picked up were extremely small, around 200 nm in diameter. These microbes though reported to be among the smallest cellular life forms, have not been cultured yet. It is also to be seen whether they have enough genes to be capable of independent existence or they are symbiotic or are parasitic.Only further detailed scientific studies will prove that these organisms are the smallest to be ever found and that they can reproduce. If this turns out to be correct we might need to reconsider existing paradigm for minimum requirements for life. The authors further noted that this community of microbes is relevant to generate potential probing strategies for life on other planets, especially on Mars. It may thus influence the search for microscopic life forms elsewhere in the solar system a discovery that will prove that life is not unique to earth.</sec></body><back><ref-list><title>References1Baker

Tyson

Webb

Flanagan

Hugenholtz

Allen

Banfield

(2006). Lineages of acidophilic archaea revealed by community genomic analysis. Science, 314: 1933–1935.2Tyson

Chapman

Hugenholtz

Allen

Ram

Richardson

Solovyev

Rubin

Rokhsar

Banfield

(2004). Community structure and metabolism through reconstruction of microbial genomes from the environment. Nature, 428: 37–43.