Sexually transmitted bug is the strongest organism

Pound-for-pound, it's the strongest organism ever. This mighty beast is the gonorrhea bacterium – the strongest creature alive.

These tiny creatures can pull with a force equal to 100,000 times their body weight – as though a human could drag 10 million kilos.

Many bacteria produce filaments called pili. These are a hundred times as long as they are wide and up to ten times longer than the bacterium itself. They can also contract. Scientists knew that Neisseria gonorhoeae bacteria use "type four" pili to crawl along a surface and to attach to cells and infect them.

What they didn't know was that these bacteria can bundle pili together to exert long, strong pulls. Michael Sheetz and colleagues at Columbia University in New York put the bacteria in a field of tiny gel "pillars" and measured the amount the bacteria could bend them as a way of measuring the force of their pull.

Short and long

They mostly saw a lot of short grabs. But one pull in a hundred started out at the same strength as these short pulls, then increased in increments about equal to the force of the original pull, as if the bacteria were calling in more individual pili to help out the first.

This eventually resulted in a pull that was up to ten times stronger than the initial short grab, and it could last for several hours.

See video of the bacteria pulling the pillars here and here.

Electron microscopic images confirmed the bundles. They also revealed that the reason scientists have not seen this before is because a protein usually added to bacterial culture medium happens to block it.

Great motor

The actual force the bacteria exerted was around a nanoNewton, or one billionth of a Newton, the force you would need to accelerate a kilogram by a metre per second squared.

Not a lot – but it means the bacteria can pull with a force equivalent to 100,000 times its bodyweight, and hold it. This, say the authors, makes the retraction protein in the pili "the strongest biological motor known to date".

"This constitutes a new paradigm for the generation of forces in the biological realm," Sheetz and colleagues say, and could completely change our understanding of the way gonorrhea bacteria muscle up to cells and infect them.

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I'll grow marigolds on the moon, says scientist

Marigolds could be growing on the moon by around 2015, if an ambitious effort by scientists pays off.

In what marks an important step towards helping lunar colonists grow their own food, a Ukrainian team, working with the European Space Agency, ESA, has shown that marigolds can grow in crushed rock very like the lunar surface, with no need for plant food.

	Marigolds were shown to survive in crushed rock

The research was presented at the European Geosciences Union meeting in Vienna, by Dr Bernard Foing of ESA, director of the International Lunar Exploration Working Group, and father of the SMART-1 moon probe, who believes it is an important milestone because it does away with the need to bring bringing nutrients and soil from Earth.

He has worked with Natasha Kozyrovska and Iryna Zaetz from the Ukranian Academy of Sciences in Kiev, who planted marigolds in crushed anorthosite, a type of rock found on Earth which is very similar to lunar soil, called regolith.

They did not grow well until the team added different types of bacteria, which made them thrive; the bacteria appeared to leach elements from the rock that the plants needed, such as potassium.

Even better, bacteria are able to withstand extremely tough conditions, so would be an ideal way to fertilise lunar crops. “That is the new aspect of this work,” says Dr Foing, who presented the study at the EGU meeting, said there was no reason in principle why the same idea could not bear fruit on the Moon itself.

He is pinning his hopes on a ESA proposal for a mission called Moon Next, which would probably deploy a roving vehicle in about 2015, or on a subsequent Lunar Logistics Lander, scheduled for 2016-17.

As well as marigolds, he says that tulips, cabbages and arabidopsis (a weed, the most studied plant on the planet) could be grown on the moon.

Tulips are handy because they can be frozen, transported long distances and grown with little nourishment. Combined with algae, an enclosed artificial atmosphere and the bacterially enhanced lunar soil, they could form the basis of a precursor lunar “ecosystem.”

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How Does Global Warming Affect Wildlife?

The National Wildlife Federation considers global warming to be "the most dangerous threat to the future of wildlife." Here are just some of the species being dramatically impacted by global warming.

	Adelie Penguins When many of us think of Antarctica, it is with visions of waddling, tuxedoed penguins. Today, however, these iconic creatures may be in peril as a result of changes to their climate. Rising temperatures are causing the amount of sea ice to diminish, which in turn causes the amount of algae in the water to decrease. Many tiny organisms, including the krill shrimp which forms the foundation of the Adelie penguin’s diet, cannot survive without this important food source.
	Caribou Almost everyone knows how annoying mosquitoes can be, but if you happen to be a caribou, these common summertime pests can have an even bigger impact. This is because warming Arctic temperatures have caused an explosion in these insects' populations. As caribou expend more energy shooing the pests away, they decrease the amount of food that they eat and energy that they conserve in preparation for the coming winter months. Female caribou are particularly at risk as the effort of birthing and raising the new generation takes enormous energy.
	Monarch Butterflies Brilliant orange and black monarchs are among the most easily-recognizable of the butterfly species which call the Americas home. Their migration takes them as far north as Canada and, during the winter months, as far south as Mexico City. It is here that changing conditions could cause their demise if current climatic trends continue into the future. In Mexico, the butterflies amass themselves in fir trees which provide shelter from rain and temperatures which often dip below freezing. As rainfall worldwide continues to increase, the protection that these trees provide may not be enough to shield the butterflies from these hazards. One mass die-off occurred in 2002; scientists fear that this is the first of many similar incidents.
	Migratory Songbirds The songs of many migratory birds, such as this Western tanager, are welcomed symbols of springtime. Warmer seasons worldwide may mean that you won’t be hearing some of those old familiar songs in years to come, however, as songbirds are particularly sensitive to changes to both temperatures and their habitats.
	Polar Bears Polar bears, like their favored springtime prey the ringed seal, depend heavily on sea ice for their survival. Polar bears move from ice flow to ice flow in search of the young seals. With rising temperatures, the thinning ice leaves fewer places for both the polar bears to hunt and the seals to raise their young.
	Trout Coldwater fish, such as trout, depend on a frigid mixture of spring and glacier water to thrive. As North American temperatures continue to rise, trout stand to lose three-quarters of their current habitat. Before long, an enitre generation of Anglers will have lost the the ability to bond with friends and family while communing with nature.
	Coral Reefs Coral reefs are colorful underwater forests which teem with life and act as a natural protective barrier for coastal regions. The fishes and plants which call them home belong to some of the most diverse – and fragile – ecosystems on the planet. In one year alone, sixteen percent of the world’s coral reefs were wiped out. A sea temperature change of a mere one degree Celsius would yield similar losses. Increasing levels of carbon dioxide in the water cause additional damage to corals, leaving them defenseless against storm damage and erosion.
	Arctic Foxes The arctic fox is a marvel or environmental adaptation. Its paws are covered with thick fur to protect its feet in winter, and it is an excellent burrower which allows it to dig dens and warm itself against the arctic chill. In recent years, warmer temperatures have driven the arctic fox farther and farther north in search of more suitable, cooler habitat.

Do your part to help reduce global warming by taking the Good Neighbor Pledge today!

Next step: Watch a video on global warming and wildlife

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