PDF(Pubmed)
Abstract：
Red calcified non-geniculate coralline algae (NGCA) provide habitat structures, stabilize reef structures, and foster coral larval settlement and metamorphosis. Moreover, the microbes associated with NGCA are dependent on the NGCA host species and are affected by environmental factors; however, little is known about the influence of reef conditions and depth gradients on the associated microbial communities and NGCA. In this study, we collected NGCA under different reef conditions and depth gradients and characterized the microbial communities using the V3-V4 hypervariable regions of the 16S rRNA gene. Metagenomic analysis revealed 2 domains, 51 phyla, 123 classes, and 210 genera. The NGCA-associated bacterial communities were dominated by Proteobacteria, Bacteroidetes, Chloroflexi, Actinobacteria, and Acidobacteriota. Gammaproteobacteria and Alphaproteobacteria were the most abundant bacterial classes. Differences in microbial diversity and richness were not apparent between reef conditions and depth gradients. However, there was a significant difference in bacterial evenness among the depth gradients. The bacterial abundance associated with NGCA was greater in deep zones than in shallow zones. The shallow zone exhibited a greater relative abundance of all gene functions than the deep zone, indicating differences in the distribution of gene functions. This study showed that the microbial communities associated with red calcified NGCA are diverse, and that the depth gradient affects their abundance and evenness, highlighting the need for further research to understand the functional roles of these microbial communities in coral reef conservation.
摘要：
红色钙化非膝状珊瑚藻（NGCA）提供了栖息地结构，稳定珊瑚礁结构，培养珊瑚幼虫的定居和变态。此外，与NGCA相关的微生物依赖于NGCA宿主物种，并受环境因素的影响；然而，关于珊瑚礁条件和深度梯度对相关微生物群落和NGCA的影响知之甚少。在这项研究中,我们在不同的珊瑚礁条件和深度梯度下收集了NGCA,并使用16SrRNA基因的V3-V4高变区对微生物群落进行了表征.宏基因组分析揭示了2个结构域，51门，123班,210属。与NGCA相关的细菌群落以变形杆菌为主，拟杆菌,氯氟菌,放线菌,和酸杆菌.γ变形杆菌和α变形杆菌是最丰富的细菌类别。珊瑚礁条件和深度梯度之间的微生物多样性和丰富度差异不明显。然而,深度梯度之间的细菌均匀度存在显着差异。与NGCA相关的细菌丰度在深层区域大于浅层区域。浅区比深区表现出更高的所有基因功能的相对丰度，表明基因功能分布的差异。这项研究表明，与红色钙化NGCA相关的微生物群落是多样的，深度梯度会影响它们的丰度和均匀度，强调需要进一步研究以了解这些微生物群落在珊瑚礁保护中的功能作用。
