Metagenomic 18S rDNA reads revealed zonation of eukaryotic communities in the Yongle blue hole

• DOI: 10.3389/fmicb.2024.1420899
• Publication Date: 2024-07-29T04:53:09Z
• Authors: Hongxi Zhang; Taoshu Wei; Qingmei Li; Liang Fu; Manjie Li; Lisheng He; Yong Wang
• Keywords: metagenomics; 0303 health sciences; 03 medical and health sciences; Yongle blue hole; 18S rRNA gene; eukaryotic communities; anoxic water; Microbiology; QR1-502

The Yongle blue hole (YBH), situated in the South China Sea, represents a compelling subject of study marine microbiology due to its unique redox-layered microbial ecosystems. However, diversity and ecology eukaryotes within YBH remains underexplored. This endeavors bridge this gap through application situ filtration fixation (ISMIFF) device collect 0.22–30 μm samples from 21 water layers YBH. Subsequent extraction 18S rRNA metagenomic reads metagenomes 10 metatranscriptomes facilitated comprehensive analysis community structures. Findings revealed pronounced superiority richness eukaryotic microorganisms oxic zone compared suboxic anoxic counterparts. Notably, Dinophyceae Maxillopoda emerged as predominant taxa based on for V4 V9 regions, which showed stratification In their relative abundance suggested potential role thermo-halocline boundaries oxic-anoxic interface. Specifically, these communities, exhibited significant at 20 m (20.01%) 105 (26.13%) depths, while was prevalent 40 (22.84%), 80 (23.19%), 100 (15.42%) depths. A part organisms, identified larvae protists, were likely attracted by swarming chemosynthetic bacterial prey prevailing Furthermore, phylogenetic relationships major operational taxonomic units (OTUs) close adjacency known species, except three OTUs. conclusion, provides critical insights into vertical distribution transcriptional activity <30-μm microbes, shedding light novelty semi-enclosed holes.