Utermann Caroline, Echelmeyer Vivien A, Blümel Martina, Tasdemir Deniz
GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Am Kiel-Kanal 44, 24106 Kiel, Germany.
Faculty of Mathematics and Natural Sciences, Kiel University, Christian-Albrechts-Platz 4, 24118 Kiel, Germany.
Microorganisms. 2020 Nov 5;8(11):1732. doi: 10.3390/microorganisms8111732.
Ascidians and their associated microbiota are prolific producers of bioactive marine natural products. Recent culture-independent studies have revealed that the tunic of the solitary ascidian (sea vase) is colonized by a diverse bacterial community, however, the biotechnological potential of this community has remained largely unexplored. In this study, we aimed at isolating the culturable microbiota associated with the tunic of collected from the North and Baltic Seas, to investigate their antimicrobial and anticancer activities, and to gain first insights into their metabolite repertoire. The tunic of the sea vase was found to harbor a rich microbial community, from which 89 bacterial and 22 fungal strains were isolated. The diversity of the tunic-associated microbiota differed from that of the ambient seawater samples, but also between sampling sites. Fungi were isolated for the first time from the tunic of . The proportion of bioactive extracts was high, since 45% of the microbial extracts inhibited the growth of human pathogenic bacteria, fungi or cancer cell lines. In a subsequent bioactivity- and metabolite profiling-based approach, seven microbial extracts were prioritized for in-depth chemical investigations. Untargeted metabolomics analyses of the selected extracts by a UPLC-MS/MS-based molecular networking approach revealed a vast chemical diversity with compounds assigned to 22 natural product families, plus many metabolites that remained unidentified. This initial study indicates that bacteria and fungi associated with the tunic of represent an untapped source of putatively new marine natural products with pharmacological relevance.
海鞘及其相关微生物群是生物活性海洋天然产物的丰富生产者。最近的非培养研究表明，独居海鞘（海花瓶）的被囊被一个多样的细菌群落定殖，然而，这个群落的生物技术潜力在很大程度上仍未被探索。在本研究中，我们旨在分离与从北海和波罗的海采集的海花瓶被囊相关的可培养微生物群，研究它们的抗菌和抗癌活性，并初步了解它们的代谢产物库。发现海花瓶的被囊含有丰富的微生物群落，从中分离出89株细菌和22株真菌。与被囊相关的微生物群的多样性与周围海水样本不同，而且在采样地点之间也存在差异。首次从海花瓶的被囊中分离出真菌。生物活性提取物的比例很高，因为45%的微生物提取物抑制人类病原菌、真菌或癌细胞系的生长。在随后基于生物活性和代谢产物谱分析的方法中，七种微生物提取物被优先用于深入的化学研究。通过基于超高效液相色谱-串联质谱的分子网络方法对选定提取物进行非靶向代谢组学分析，揭示了巨大的化学多样性，其中化合物被归类为22个天然产物家族，还有许多代谢产物仍未鉴定。这项初步研究表明，与海花瓶被囊相关的细菌和真菌代表了一个潜在的具有药理学相关性的新海洋天然产物的未开发来源。
