MAC-EXP: Development of a pressurised sampling, experimentation and cultivation system for deep-sea sediments

MAC-EXP：开发深海沉积物加压采样、实验和培养系统

• 批准号: NE/I024232/1
• 负责人: Ronald Parkes
• 金额: $ 6.93万
• 依托单位: CARDIFF UNIVERSITY
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2012
• 资助国家: 英国
• 起止时间: 2012 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FI024232%2F1
• 关键词: MAC; EXP; Development; pressurised; sampling

Most deep-sea organisms live under high pressure in the "piezosphere" (the volume of the deep-sea at > 1000 m of water depth or > 10MPa pressure) and depend on organic particles sinking down from the surface waters for food. The most abundant organisms by far in marine sediments are prokaryotes (bacteria and archaea), and the biomass of the bacteria and archaea is so great that they are thought to be the main agents of the remineralisation of organic matter, a process which releases nutrients back into the water column and is thus very important for ocean productivity and, for example, fisheries. But our knowledge of deep-sea prokaryote diversity and ecosystem function is scarce. With fishing, mining, oil and gas exploration increasingly taking place in deeper waters, we urgently need to improve our understanding of the functioning of deep-sea ecosystems in order to assess appropriately the societal and economic implications of such activities and impacts and to ensure adequate management of deep-sea biodiversity and natural resources for future generations.Unfortunately, this is not easy: the main reasons for our limited knowledge of deep-sea biodiversity and ecosystem functioning lies in the combination of its inaccessibility with the sensitivity to depressurization of deep-sea organisms and deep-sea biogeochemical processes. Pressure has significant effects on, for example, bacterial physiology or growth rates, as well as many biogeochemical processes that microorganisms conduct. In consequence, meaningful experimentation has to be carried out under in situ pressure, which results in major financial and technical constraints. Remotely Operated Vehicles allow us to conduct experimental research at the deep-sea floor, but although now possible, this is still very risky and resource-intensive, requiring sophisticated deep-sea ROVs, operated by large crews from large vessels (e.g. 11 technical staff accompany a deployment of the French deep-sea ROV VICTOR 6000; and a large research ship is needed to accommodate and deploy it), and to-date very few such systems are available. In addition, samples in most cases suffer depressurization upon retrieval, preventing further experimentation. As many deep-sea microorgansims may only be culturable without depressurization, this may explain why less than 1 % of deep-sea prokaryotes are currently in culture. Here we propose to develop a flexible, cost-effective alternative to in situ experimentation: a pressure-coring, experimentation and cultivation system that enables studies of deep-sea prokaryote biodiversity and activity, and ecosystem functioning, under ambient or manipulated pressure, temperature and oxygen conditions from any medium sized ocean going research ship with coring capability. In addition, the constant high-pressure conditions from sampling to culture overcomes limitations of in situ experiments related to depressurisation.This Multiple-Autoclave-Coring and Experimentation system (MAC-EXP) will provide the possibility to systematically test the influence of environmental parameters, such as pressure, oxygen availability or pH on deep-sea organisms and their biochemistry, as well as on rates and pathways of biogeochemical and geomicrobial processes. The system will also allow pioneering work in the field of marine biodiscovery: secondary metabolites from marine microorganisms are a rich source of chemical diversity and several marine-microbe derived compounds are now in clinical trials. Recent evidence shows that pressure-adapted bacteria from deep-sea sediments produce biologically active and unusual secondary metabolites. But no pressure-adapted bacterial species have ever been investigated for their secondary metabolites and the proposed pressurised sampling system provides the possibility to conduct such studies.

大多数深海生物都生活在“压电圈”中的高压下（深海的体积> 1000 m的水深或> 10mpa压力），并依赖于从地表水中下沉的有机颗粒作为食物。迄今为止，海洋沉积物中最丰富的有机体是原核生物（细菌和古细菌），细菌和古细菌的生物量是如此之大，以至于它们被认为是回想起有机物的主要代理，这一过程将营养恢复到水柱中，因此对海洋生产力非常重要，例如，海洋生产力和海洋生产力和渔业非常重要。但是，我们对深海原核生物多样性和生态系统功能的了解很少。随着钓鱼，采矿，石油和天然气勘探的越来越多地在深水中进行，我们需要提高对深海生态系统功能的理解，以评估这种活动和影响的社会和经济影响，并确保对未来的生物效果的充分性，这对有限的知识并不容易。在于其难以接近的结合与对深海生物和深海生物地球化学过程降低的敏感性的结合。压力对例如细菌生理或生长速率以及微生物进行的许多生物地球化学过程具有重大影响。因此，必须在原位压力下进行有意义的实验，从而导致重大财务和技术限制。远程操作的车辆使我们能够在深海楼层进行实验研究，但是尽管现在可能，但这仍然是风险和资源密集型的，需要大型船只的大型机组人员经营的复杂的深海ROV（例如，11名技术人员陪同法国深入的Rovor 6000次陪同，需要进行大型研究和一些系统的系统，并且可以容纳很少的系统，并且可以使用很少的部门，并且可以使用它。此外，在大多数情况下，样品在检索后遭受抑制作用，从而阻止了进一步的实验。由于许多深海微怪异可能只能在不抑制的情况下进行培养，因此这可以解释为什么目前不到1％的深海原核生物在文化中。在这里，我们建议在原位实验中开发一种灵活的，具有成本效益的替代方法：一种压力，实验和培养系统，可以研究深海脑脑脑培养物生物多样性和活动，以及在任何中型海洋研究船上的环境或操纵压力，温度和氧气状况下，在环境或操纵的压力，温度和氧气下的生态系统功能。 In addition, the constant high-pressure conditions from sampling to culture overcomes limitations of in situ experiments related to depressurisation.This Multiple-Autoclave-Coring and Experimentation system (MAC-EXP) will provide the possibility to systematically test the influence of environmental parameters, such as pressure, oxygen availability or pH on deep-sea organisms and their biochemistry, as well as on rates and pathways of biogeochemical and地球生物过程。该系统还将允许在海洋生物发现领域进行开创性的工作：海洋微生物的二级代谢产物是化学多样性的丰富来源，现在正在临床试验中进行了几种海洋微生物。最近的证据表明，来自深海沉积物的压力适应细菌会产生生物活性和异常的继发代谢物。但是，尚未研究过压力适应的细菌物种的次级代谢产物，并且提出的加压采样系统提供了进行此类研究的可能性。