Heterotrophic microorganisms in Arctic hydrothermal sediments - the ecological roles and impact of their CAZymes repertoire

北极热液沉积物中的异养微生物 - 其 CAZymes 库的生态作用和影响

• 批准号: 467458523
• 负责人: Dr. Katharina Saß
• 金额: --
• 依托单位: Department of Biology
• 依托单位国家: 德国
• 项目类别: WBP Fellowship
• 财政年份: 2021
• 资助国家: 德国
• 起止时间: 2020-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/467458523?language=en
• 关键词: Heterotrophic; microorganisms; Arctic; hydrothermal; sediments

Deep-sea hydrothermal vents are among the most extreme habitats on Earth and represent interesting targets for marine bioprospecting and biodiscovery. Microbial communities at deep-sea hydrothermal vents are often dominated by chemolithoautotrophic microorganisms that use simple chemical compounds as energy sources. However, the full extent of their heterotrophic capabilities is still being explored. New microbial solutions are urgently needed in the bioprocessing industry, where the degradation of complex organic materials is often a major challenge. To meet these needs, novel in situ incubators have already been developed and tested to see if the use of degradation-resistant materials from the wood processing industry causes changes in the microbial community structure in hot marine hydrothermal sediments. Differences in the microbial community structure were observed depending on the used material, chamber depth below the seafloor, and/or temperature. 16S rRNA amplicon sequencing revealed a high proportion of heterotrophic microbial lineages related to cultivated members within the Thermotogales. However, significant proportions of previously uncultured and novel Thermotogales and Bacteroidetes were also identified. In addition, several new lineages of not yet cultured thermophilic Archaea and Bacteria were observed. Based on this, the goal of the proposed project is to cultivate and isolate various heterotrophic bacteria from Arctic hydrothermal sediments. Enrichment cultures with different substrates such as cellulose and chitin will be screened for the presence of polysaccharide degrading enzymes identified in already available metagenomes. Targeted cultivation strategies will be performed to select the new heterotrophic bacteria. Genomic analyses for different metabolic capacities will support these. Functional analyses at the single cell level will help identify and isolate the target bacteria based on their in situ activity in mixed cultures. Finally, novel heterotrophic bacteria will be characterized in detail with respect to morphology, physiology and their genome. Metatranscriptomic approaches under modified incubation conditions will also provide information about the carbohydrate-active enzymes (CAZymes). These will be investigated and characterized in more detail. Thus, based on metagenomes and metatranscriptomes, new enzymes for various industries can be discovered. The metabolic secrets and the capacity of the microbiomes of hydrothermal vents in the Arctic deep-sea will be revealed within this project.

深海热液喷口是地球上最极端的栖息地之一，是海洋生物勘探和生物发现的有趣目标。深海热液喷口的微生物群落通常以化能自养微生物为主，它们使用简单的化合物作为能源。然而，它们的异养能力的全部范围仍在探索中。生物加工行业迫切需要新的微生物解决方案，复杂有机材料的降解往往是一个重大挑战。为了满足这些需求，新型原位培养箱已经被开发出来并进行了测试，以观察木材加工业中的抗降解材料的使用是否会导致热海洋热液沉积物中微生物群落结构的变化。根据所使用的材料、海底以下的舱室深度和/或温度，观察到微生物群落结构的差异。 16S rRNA 扩增子测序揭示了较高比例的异养微生物谱系与栖热袍菌目中的培养成员相关。然而，还鉴定出了很大比例的以前未培养的新型栖热袍菌目和拟杆菌门。此外，还观察到了一些尚未培养的嗜热古菌和细菌的新谱系。基于此，该项目的目标是从北极热液沉积物中培养和分离各种异养细菌。将筛选具有不同底物（例如纤维素和甲壳素）的富集培养物，以确定是否存在已可用的宏基因组中鉴定的多糖降解酶。将执行有针对性的培养策略来选择新的异养细菌。对不同代谢能力的基因组分析将支持这些观点。单细胞水平的功能分析将有助于根据目标细菌在混合培养物中的原位活性来识别和分离目标细菌。最后，新型异养细菌将在形态、生理学及其基因组方面进行详细表征。改良孵育条件下的宏转录组学方法还将提供有关碳水化合物活性酶 (CAZymes) 的信息。这些将被更详细地研究和表征。因此，基于宏基因组和宏转录组，可以发现用于各个行业的新酶。该项目将揭示北极深海热液喷口的代谢秘密和微生物组的能力。