Microbiologically influenced corrosion of maritime platforms

已经进行了相当数量的研究，以确定形成的破坏性生物膜对金属系统的影响，其中大多数是在石油和天然气以及能源工业中进行的。尽管近年来人们对检测、监测和预防腐蚀的有效手段越来越感兴趣，但对微生物群落与MIC的关系的了解仍然缺乏。因此，参与反应的细菌联合体的特性尚不完全清楚，这可能妨碍针对此类问题制定有针对性的缓解战略。为了能够为海上平台的防腐策略的未来做出贡献，该博士课程将复制在现场发现的多微生物群落，使用非培养技术，以了解可能在BAE系统的海上平台上形成有问题的生物膜的细菌联合体。拟议的工作将分为三个阶段，每个阶段的相关目标如下：表征在选定码头发现的腐蚀性生物膜，BAE系统用于海上平台存储和维护；鉴定和分离参与生物膜活动的关键微生物构建合成实验室联盟以复制从海洋平台中鉴定出的不同群落利用合成群落确定不同细菌在这些生物膜中的作用，从而了解如何控制与之相关的微生物影响腐蚀（MIC）在实验室中研究单个微生物的技术已经建立和完善技术的进步现在能够在DNA水平上对复杂的多微生物系统进行不依赖培养的表征，消除了在实验室中最容易分离生长的生物的偏见。最近，通过结合这两种技术，在微生物学的几个领域取得了进展，在实验室中构建人工群落，可以用来探测个体成员的作用，并观察群落的组成如何随着时间和环境压力而变化。生物膜样品将从感兴趣的位置采集，制备总DNA并用于条形码16S rRNA基因特异性PCR，然后进行下一代DNA测序以确定生物膜中的细菌种类组成。该信息将用于告知富集实验，以便从生物膜样品中分离出关键微生物群的代表。只要有可能，分离物将与原始生物膜中的主要参与者相对应，即使在不可能的情况下（因为环境中复杂的多微生物群落中的优势生物通常不容易在实验室培养基中生长），也将获得关键功能基团的代表。这将允许在实验室中对人工构建的微生物群落进行后续实验，这将允许在流动电池系统中以各种组合研究各种促进和抑制腐蚀的微生物的影响，这将允许通过电化学方法进行观察。研究结果有望为未来的防腐策略提供信息，包括使用非杀菌剂来改变生物膜的行为，以及开发含有关键防腐/防污微生物的功能涂层。

A considerable amount of research has been performed to determine the effects of destructive biofilms formed on metallic systems, most of which have been in the oil and gas, and energy industries. Although in more recent years there has been an increased interest in an effective means of detecting, monitoring, and preventing corrosion an understanding of the microbial community consortium in association with MIC is still lacking. Consequently, the identities of the bacterial consortia involved in the reactions are not fully known, which can impede the formulation of a targeted mitigation strategy for such issues. To be able to contribute to the future of anti-corrosion strategies of maritime platforms this Ph.D. programme will replicate the polymicrobial community identified at field sites, using culture-independent techniques, to develop an understanding of the bacterial consortia which could form problematic biofilms on maritime platforms for BAE systems. The proposed work will be separated into three stages and the objectives associated with each of these are as follows: Characterise corrosive biofilms found at selected docks, used by BAE systems for maritime platform storage and maintenance, to identify and isolate key microorganisms involved in biofilm activities Construct synthetic laboratory consortia to replicate the different communities identified from maritime platforms Use the synthetic community to define the roles of different bacteria in those biofilms enabling an understanding of how microbiologically influenced corrosion (MIC) associated with them might be controlled Techniques for studying individual microorganisms in the laboratory are well established and advancements in technologies now enable culture-independent characterisation of complex polymicrobial systems at the DNA level, removing the bias of which organisms are easiest to grow in isolation in the laboratory. More recently, progress has been made in several areas of microbiology by combining these two techniques, to construct artificial consortia in the laboratory that can be used to probe the roles of the individual members and to observe how the composition of the consortium changes with time and environmental stresses. Biofilm samples will be taken from sites of interest and total DNA will be prepared and used for barcoded 16S rRNA gene-specific PCR followed by next generation DNA sequencing to determine the bacterial species composition in the biofilms. This information will be used to inform enrichment experiments to isolate representatives of key groups of microorganisms from the biofilm samples. Wherever possible the isolates will correspond to the major players in the original biofilms, though even where this is not possible (because dominant organisms in complex polymicrobial communities in the environment often do not grow easily in laboratory media), representatives of the key functional groups will be obtained. This will allow subsequent experiments with artificially constructed communities of microorganisms in the laboratory, which will allow the effects of various corrosion promoting and corrosion inhibiting microorganisms to be studied in various combinations in a flow cell system that will allow observations to be made by electrochemical methods. The results are expected to inform future anti-corrosion strategies, including use of non-biocidal agents to modify biofilm behaviour and development of functional coatings containing key anticorrosion/ antifouling microorganisms.