Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Small, Cold, and Hungry: Ultra-Small Microbes from a 120,000-Year-Old Greenland-Glacier Ice Sample

27.05.2004


Material from a 120,000-year-old Greenland Glacier ice sample showing micro-microbes (small white oblong forms) and larger materials.


One of the novel micro-microbes isolated from a 120,000-year-old Greenland Glacier ice sample


The discovery of millions of micro-microbes surviving in a 120,000-year-old ice sample taken from 3,000 meters below the surface of the Greenland glacier will be announced by Penn State University scientists on 26 May 2004 at the General Meeting of the American Society for Microbiology in New Orleans, Louisiana. The discovery is significant because it may help to define the limits for life on Earth as well as elsewhere in the universe, such as on cold planets like Mars.

According to Penn State researchers Vanya I. Miteva, research associate, and Jean E. Brenchley, professor of microbiology and biotechnology, the majority of the microbes they discovered in an ice-core sample taken from the glacier were less than 1 micron in size--smaller than most commonly known bacteria, which range from 1 to 10 microns. In addition, a large portion of the cells appeared to be even smaller and passed through filters with 0.2-micron pores. The scientists are interested in understanding how microbial life can be preserved in polar ice sheets for hundreds of thousands of years under stresses that include subzero temperatures, desiccation, high pressures, and low oxygen and nutrient concentrations. Because the ice was mixed with the ancient permafrost at the bottom of the glacier, the microbes could have been trapped there for perhaps millions of years.

"We are particularly interested in the formation of ultra-small cells as one possible stress-survival mechanism, whether they are starved minute forms of known normal-sized microbes or intrinsically dwarf novel organisms, and also whether these cells are able to carry on metabolic processes while they are so highly stressed," Miteva says. Physiological changes that accompany the reduction of a cell’s size may allow it to become dormant or to maintain extremely low activity with minimal energy.



"Many of these ice-core microbes are related to a variety of ultra-small microorganisms from other cold environments that have been shown to use different carbon and energy sources and to be resistant to drying, starvation, radiation, and other stress factors. Their modern relatives include the model ultra-micro bacterium Sphingopyxis alaskensis, which is abundant in cold Alaskan waters," Brenchley reports. She and Miteva are in the process of closely examining all the microbes they found in order to determine the identities and diversity of the species and to look for ones with novel functions.

The researchers used a variety of methods including repeated sample filtrations, electron microscopy, and a modified technique of flow cytometry to quickly reveal the number of cells and to estimate their different sizes, DNA content, and other characteristics. Miteva and Brenchley discovered cells with many different shapes and sizes, including a large percentage that were even smaller than filter-pore sizes of only 0.2 microns. "It appears that these ultra-small microbes often are missed in research studies because they pass through the finest filters commonly used to collect cells for analysis," Miteva says.

"Scientists believe these dwarf cells belong to the ’uncultured majority’ because they are among the 99 percent of all microbes on Earth that have never been isolated and cultured for study. Obtaining such ’isolates’ is necessary in order to describe a new organism, study its cell size, examine its physiology, and assess its ecological role. We now know just the tip of the iceberg of all the microbes that exist on Earth, and it generally is believed that a large portion of these unknown microbes are very small in size," Miteva says.

"A major challenge is to develop novel approaches for growing some of these previously unculturable organisms," Brenchley says. "At present, no single established protocol exists and little is known about the recovery of these stressed and possibly damaged cells from a frozen environment that subjects them to severe conditions for long periods." Some of the cells that Miteva and Brenchley were successful in cultivating required special conditions and up to six months to form initial colonies. The researchers discovered that these colonies grew more rapidly during further cultivation and that most continued to form predominantly small cells.

"Our study of the abundance, viability, and identity of the ultra-small cells existing in the Greenland ice is relevant to discovering how small life-forms can be; how cells survive being small, cold, and hungry; and what new tricks we need to develop in order to cultivate these small cells," Miteva says. "This study is part of the continuing quest by microbiologists to overcome the current limitations of our methods and to answer the big question, ’What new microbes are out there and what are they doing?’"


This research was supported by the Department of Energy (Grant DE-FG02-93ER20117) and the Penn State Astrobiology Center (NASA-Ames Cooperative Agreement No. NCC2-1057).

CONTACTS before 22 May and after 27 May:
Vanya I. Miteva: (+1)814-865-3330 (lab phone and fax), vim1@psu.edu
Jean E. Brenchley: (+1)814-865-3330 (lab phone and fax), jeb7@psu.edu
Barbara Kennedy (PIO): (+1)814-863-4682, science@psu.edu

CONTACTS from 22 May to 27 May:
Press Room at American Society for Microbiology meeting: 504-670-4240
Barbara Kennedy (PIO): (+1)814-863-4682, science@psu.edu

Barbara Kennedy | Penn State
Further information:
http://www.science.psu.edu/alert/Brenchley5-2004.htm

More articles from Life Sciences:

nachricht ADP-ribosylation on the right track
26.04.2018 | Max-Planck-Institut für Biologie des Alterns

nachricht Flavins keep a handy helper in their pocket
25.04.2018 | University of Freiburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Why we need erasable MRI scans

New technology could allow an MRI contrast agent to 'blink off,' helping doctors diagnose disease

Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is...

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Why we need erasable MRI scans

26.04.2018 | Medical Engineering

Balancing nuclear and renewable energy

26.04.2018 | Power and Electrical Engineering

Researchers 3-D print electronics and cells directly on skin

26.04.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>