Molecular biology goes to extremes

The portable DNA testing kit worked in extreme conditions

By Dr David Whitehouse BBC News Online science editor

Equipped with a portable lab, scientists have conducted genetic tests on the bacteria that thrive in one of the most inhospitable places on Earth: Antarctica's Dry Valleys.

It was primitive, cramped, and cold, but next time, we will bring... a coffee machine

Dr Craig Cary

It is believed to be the first time that DNA fingerprinting of soil microbes has been performed in the field on the White Continent.

The two-week research expedition was the first in a series to assess the diversity of micro-organisms that inhabit Antarctica.

According to Dr Craig Cary from the University of Delaware, US, the work will help us understand low-temperature life and possibly how life might survive on other planets.

At the limit

Unlike most of Antarctica, the Dry Valleys are not covered in snow and ice but are a vast region of exposed soil and rock, punctuated by icy lakes.

The extreme: Investigating the Dry Valleys

Some of these areas - which are largely confined to the margins of the continent, nearby islands, and the Antarctic Peninsula - may not have had any rain for millions of years.

Dr Cary is studying the microscopic life that can survive these demanding cold conditions. He has previously studied the microbes that live in hydrothermal vents found on the ocean floor.

"While vent microbes set the upper end of the temperature scale in the marine environment, the polar regions set the lower limit in the terrestrial environment," he said.

Tech spin-offs

"Past research has shown that the soils of the Dry Valleys support a diverse assemblage of micro organisms. Yet, how they survive and what they are doing remains largely unknown.

Cold, dry and almost lifeless

"Research on heat-loving vent bacteria has yielded enzymes that can be used as industrial catalysts in certain high-temperature operations like pharmaceuticals manufacturing," he added.

"In examining polar microbes, scientists might identify new biotechnological tools and products for use at extremely cold temperatures, as well as shed light on the possibility of life on other planets."

To determine if they were succeeding in collecting a diversity of polar microbes in their sampling operations, the scientists needed to be able to examine the tiny lifeforms at the genetic level.

Cross-legged on ice

To conduct the DNA tests, the researchers used the Mobile Molecular Laboratory, made by MJ Research, Inc, and donated to the expedition by Geneworks of Adelaide, Australia.

The scientists worked in the field for nearly two weeks. Every few days, they were flown by helicopter to new sampling locations in the Dry Valleys.

The researchers would sit cross-legged on the floor of a tent or on a first aid box doing delicate genetic tests, including DNA extractions, electrophoresis, and PCR (polymerase chain reaction) analyses as the wind howled around them.

Antarctica's Dry Valleys are surrounded by snowfields

At the end of 13 days of field work, the researchers had run six successful experiments that provided valuable genetic information on the samples they were collecting.

"The beauty of doing this testing on site is that we can be sure that we get the diversity of microbes we came for instead of collecting samples and then confirming what we got - or didn't get - weeks later back in the lab," said Dr Cary.

"Sure, this time, it was primitive, cramped, and cold, but next time, we will bring a dedicated and more spacious laboratory structure, with a table, folding chairs, a heater, and a coffee machine - a little luxury in the Dry Valleys!"

The expedition was led by scientists from the University of Western Cape Town in South Africa, the University of Waikato in New Zealand, the University of Delaware in the United States, and University College, London, UK.