病毒与原核生物的比率(VPR),这反映了病毒在其宿主中的数量优势,已被提议作为评估病毒和原核生物之间关系的替代。以前的研究表明,VPR值在各种底栖生态系统内部和之间波动超过六个数量级,平均值约为10。我们假设这种高VPR值主要是由于病毒和原核生物的不准确计数(例如,离心处理可能导致VPR高估3-4倍)。在这项研究中,我们评估了处理方法对VPR值测定的影响.使用优化的程序,我们调查了31个地点的海洋底栖VPR,从潮间带穿过大陆架到深海平原,并在两个相反的潮间带生境(泥沙和沙质)中评估了其每月变化。通过收集来自37种出版物的135种表层沉积物的VPR数据点,我们揭示了离心对公布的VPR值的影响,并根据可靠的数据在更大范围内描述了VPR值的空间分布。结果表明,常用的离心法可能会导致VPR值的高估,比使用稀释法获得的VPR值高大约一个数量级,而其他处理步骤对VPR的影响有限。我们的分析表明,底栖VPR值较低,在时间和空间尺度上变化较小,在海洋和淡水栖息地中,平均VPR约为2。在潮间带观察到VPR中微不足道的季节性模式,在高温下发生较低的VPR值。VPR空间分布主要与沉积物phaeophylina有关,表明上部水柱的营养条件和有机物向底部的沉降是影响VPR值的关键因素。底栖生境的平均VPR比在中上层生境中观察到的平均VPR低大约一个数量级,并且变化要小得多。表明病毒与宿主的关系和病毒在两个生态系统中的生态功能可能有很大的不同。
The virus-to-prokaryote ratio (VPR), which reflects the numerical dominance of viruses over their hosts, has been proposed as a proxy for assessing the relationship between viruses and prokaryotes. Previous studies showed that VPR values fluctuate over six orders of magnitude within and across various benthic ecosystems, with an average value of approximately 10. We hypothesize that this high VPR value is largely due to the inaccurate enumeration of viruses and prokaryotes (e.g., centrifugation treatments may lead to a three-fourfold overestimation of VPR). In this study, we evaluated the impact of processing methods on the determination of VPR values. Using an optimized procedure, we investigated the marine benthic VPR at 31 sites, from intertidal zones through continental shelves to abyssal plains, and assessed its monthly variation in two contrasting intertidal habitats (muddy-sand and sandy). By compiling 135 VPR data points of surface sediments from 37 publications, we reveal the effect of centrifugation on published VPR values and describe the spatial distribution of VPR values on a larger scale based on reliable data. The results showed that the commonly used centrifugation method may result in an overestimation of VPR values that are approximately one order of magnitude higher than those obtained using the dilution method, while other processing steps had a limited impact on the VPR. Our analysis indicates that the benthic VPR value is low and less varied across temporal and spatial scales, fluctuating mostly within 10, and the average VPR is approximately 2 in both marine and freshwater habitats. An insignificant seasonal pattern in the VPR was observed in the intertidal zone, with lower VPR values occurring at high temperatures. The VPR spatial distribution was primarily associated with sediment phaeophytin a, suggesting that the trophic conditions of the upper water column and the sedimentation of organic matter to the bottom are the key factors affecting VPR values. The mean VPR in benthic habitats is approximately one order of magnitude lower and much less varied than that observed in pelagic habitats, indicating that the virus-host relationship and the ecological function of viruses in the two ecosystems may be very different.