科学家在加拿大一处矿井地下2.4公里处，发现了微生物

 

 

Amongst all of Earth's abundant life, microorganisms have proven time and time again that they can live just about anywhere. Now, we have more evidence to add to the pile: living microbes have been found some 2.4 kilometres (1.5 miles) below the surface in a Canadian mine, a long way away from sunlight and clean air.

 

在地球上所有丰富的生命中，微生物一次又一次地证明，它们可以在任何地方生存。现在，我们有更多的证据可以证明这一点：在加拿大一个远离阳光和干净空气的矿井里，在地表以下2.4公里(1.5英里)处发现了活的微生物。

 

Researchers think that it's the presence of sulphates in the ancient underground water that's keeping these microscopic life forms alive; they're 'breathing' the sulphates to survive, rather than relying on oxygen.

 

研究人员认为，正是古代地下水中硫酸盐的存在，使这些微生物得以存活——它们通过“呼吸”硫酸盐来生存，而不是依赖氧气。

 

The cave water itself is actually one of the oldest known pools of water on Earth, cut off from the surface of the planet for millions of years.

 

洞穴水本身实际上是地球上已知最古老的水池之一，它与地球表面隔绝了数百万年。

 

Finding life down at these depths would have been considered impossible until quite recently, due to the lack of the chemical ingredients that normally support living things.

 

直到最近，由于缺乏通常支持生物生存的化学成分，在这样的深度下寻找生命还被认为是不可能的。

 

(Stable Isotope Laboratory, University of Toronto)

 

"Even in the modern scientific era, the planet's biosphere was thought of as a thin veneer on or near the surface of the planet, with life primarily dependent on photosynthesis to thrive," write the researchers in their paper.

 

研究人员在他们的论文中写道：“即使在现代科学时代，地球的生物圈也被认为是地球表面或其附近的一层薄薄的薄片，生命主要依靠光合作用来生长。”

 

That hypothesis has been changing, though. Scientists took samples taken from deep inside the mine, and after testing that the prehistoric water had not been contaminated with water from mining operations closer to the surface, looked for signs of metabolic activity.

 

不过，这种假设一直在改变。科学家们从矿井深处采集了样本，并在测试了史前水没有被地表附近采矿作业的水污染后，开始寻找代谢活动的迹象。

 

Having added food sources to incubated cells taken from the samples, the team found that the food was indeed being processed.

 

在给从样品中提取的培养细胞添加了食物来源之后，研究小组发现，食物确实在被加工。

 

The results don't tell us exactly what the microbes are, but it does show that microbes – specifically sulphate reducers – are active, forging a living from the chemical reactions between water and rock deep below the surface.

 

研究结果并不能确切地告诉我们微生物是什么，但它确实表明了微生物——特别是硫酸盐还原剂——是活跃的，通过水和岩石在地表深处的化学反应来维持生命。

 

"It's great to be able to see that they're there," geologist Barbara Sherwood Lollar, from the University of Toronto in Canada, told Catherine Offord at The Scientist.

 

加拿大多伦多大学的地质学家芭芭拉·舍伍德·洛拉尔，告诉科学家凯瑟琳·奥福德：“能看到它们在那里，真是太好了。”

 

"We were confident that they likely were, but it's a very long journey from that to a series of hard lines of evidence that actually supports it."

 

“我们相信他们很有可能是这样，但从这一点到一系列支持这一观点的确凿证据，还有很长的路要走。”

It backs up previous work from the same researchers that had found evidence of microbes living in this water – rich in hydrogen and sulphates – in the past. Now we know that the cycle of life is continuing.

 

这一发现支持了先前研究人员的工作，这些研究人员在过去发现了生活在这种富含氢和硫酸盐的水中的微生物的证据。现在我们知道生命的循环还在继续。

 

While bacteria living deep inside mines might not have much of an impact on your day-to-day life, it expands our understanding of what life is, and how it can survive even in the harshest of environments.

 

虽然生活在矿井深处的细菌可能对你的日常生活没有多大影响，但它扩大了我们对生命是什么、以及它如何在最恶劣的环境中生存的理解。

 

That in turn informs everything from our search for life outside the Solar System, to investigating subterranean biospheres here on Earth. What's happening in Kidd Creek Mine in Canada might be happening elsewhere too.

 

这反过来又启发了我们对太阳系外生命的探索，以及对地球地下生物圈的研究。发生在加拿大基德克里克矿的事情，也可能发生在其他地方。

 

And there could well be more to come, in terms of identifying both active and inactive microbes in this underground environment, something which is beyond the scope of this latest study.

 

在识别地下环境中活跃和不活跃的微生物方面，还有更多的事情要做，这超出了这项最新研究的范围。

 

"This paper is groundbreaking, so to speak," microbial ecologist John Spear from the Colorado School of Mines, who wasn't involved in the work, told The Scientist.

 

“可以说，这篇论文是开创性的。”科罗拉多矿业学院的微生物生态学家约翰·斯皮尔告诉这位科学家，他没有参与这项研究。

 

"They were able to get an idea of the amount of native microbial biomass... and they were able to confirm that the waters that the microbes are living in are host waters – they're not contaminated or impacted by water coming from the surface."

 

“他们能够了解本地微生物的生物量……能够确认微生物所生活的水域是宿主水域——没有受到来自地表水的污染或影响。”

 

The research has been published in the Geomicrobiology Journal.

 

这项研究已发表在《地球微生物学杂志》上。