Recent big data analyses have illuminated marine microbial diversity from a global perspective, focusing on planktonic microorganisms. Here, we analyze 2.5 terabases of newly sequenced datasets and the Tara Oceans metagenomes to study the diversity of biofilm-forming marine microorganisms. We identify more than 7,300 biofilm-forming ‘species’ that are undetected in seawater analyses, increasing the known microbial diversity in the oceans by more than 20%, and provide evidence for differentiation across oceanic niches. Generation of a gene distribution profile reveals a functional core across the biofilms, comprised of genes from a variety of microbial phyla that may play roles in stress responses and microbe-microbe interactions. Analysis of 479 genomes reconstructed from the biofilm metagenomes reveals novel biosynthetic gene clusters and CRISPR-Cas systems. Our data highlight the previously underestimated ocean microbial diversity, and allow mining novel microbial lineages and gene resources.

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The reliability of MyotonPRO that can monitor the mechanical properties of tissues is still unclear. This study aimed to analyze the within-day inter-operator and between-day intra-operator reliability of MyotonPRO for assessing tone and stiffness of quadriceps femoris and patellar tendon at different knee angles. The tone and stiffness of healthy participants (15 males and 15 females, aged 24.7±1.6 years) in the supine and resting position were measured using the MyotonPRO device. The measurements were quantified at 0°, 30°, 60°, and 90° of knee flexion. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable change (MDC) were calculated and a Bland–Altman analysis was conducted to estimate reliability. The results indicated excellent inter-operator reliability (ICC > 0.78) and good to excellent intra-operator reliability (ICC > 0.41). The inter-operator SEM measurements ranged between 0.1–0.9 Hz and 3.8–37.9 N/m, and intra-operator SEM ranged between 0.5–1.3 Hz and 7.9–52.0 N/m. The inter-operator MDC ranged between 0.3–2.5 Hz and 10.5–105.1 N/m, and intra-operator SEM ranged between 1.1–3.3 Hz and 21.9–144.1 N/m. The agreement of inter-operator was better than that of intra-operator. The study concluded that MyotonPRO is a reliable device to detect the tone and stiffness of quadriceps femoris and patellar tendon.

In this study, we used miTAG approach to analyze the distributional pattern and fine‐scale genetic diversity of the ammonia oxidizing archaea (AOA) lineages in the global oceans with the metagenomics data sets of the Tara Oceans global expedition (2009–2013). Using the ammonium monooxygenase alpha subunit gene as a biomarker, the AOA communities in the global oceans were recovered with highly diverse operational taxonomic units that affiliated to previously defined clades, including water column A (WCA), water column B (WCB), and SCM1‐like clades. In general, the AOA communities were obviously segregated with depth (except the upwelling regions), and the communities in the euphotic zones were more heterogeneous than in the mesopelagic zones (MPZs). The WCA distributed more evenly and widely in the euphotic zone and MPZs, while WCB and SCM1‐like clade mainly distributed in MPZ and high‐latitude waters, respectively. At fine‐scale genetic diversity, SCM1‐like and 2 WCA subclades showed distinctive niche separations of distributional pattern. We further divided the AOA subclades into ecological significant taxonomic units (ESTUs), which were delineated from the distribution pattern of their corresponding subclades. For example, ESTUs of WCA have different correlations with depth, nitrate to silicate ratio, and salinity; SCM1‐like A was negatively correlated with irradiation, whereas other SCM1‐like ESTUs preferred low‐temperature and high‐nutrient conditions. Our result showed that the previously defined AOA clades and ecotypes consist of highly diverse sublineages, whose diversity might be overlooked in the past. The distribution patterns of different ESTUs imply their ecophysiological characteristics and potential roles in biogeochemical cycling.