School of Biological Sciences, University of Essex, Colchester, UK.
School of Water, Energy and Environment, Cranfield University, Cranfield, UK.
Mol Ecol Resour. 2019 May;19(3):672-690. doi: 10.1111/1755-0998.13002.
Bioaerosols (or biogenic aerosols) have largely been overlooked by molecular ecologists. However, this is rapidly changing as bioaerosols play key roles in public health, environmental chemistry and the dispersal ecology of microbes. Due to the low environmental concentrations of bioaerosols, collecting sufficient biomass for molecular methods is challenging. Currently, no standardized methods for bioaerosol collection for molecular ecology research exist. Each study requires a process of optimization, which greatly slows the advance of bioaerosol science. Here, we evaluated air filtration and liquid impingement for bioaerosol sampling across a range of environmental conditions. We also investigated the effect of sampling matrices, sample concentration strategies and sampling duration on DNA yield. Air filtration using polycarbonate filters gave the highest recovery, but due to the faster sampling rates possible with impingement, we recommend this method for fine -scale temporal/spatial ecological studies. To prevent bias for the recovery of Gram-positive bacteria, we found that the matrix for impingement should be phosphate-buffered saline. The optimal method for bioaerosol concentration from the liquid matrix was centrifugation. However, we also present a method using syringe filters for rapid in-field recovery of bioaerosols from impingement samples, without compromising microbial diversity for high -throughput sequencing approaches. Finally, we provide a resource that enables molecular ecologists to select the most appropriate sampling strategy for their specific research question.
生物气溶胶（或生物成因气溶胶）在很大程度上被分子生态学家所忽视。然而，这种情况正在迅速改变，因为生物气溶胶在公共卫生、环境化学和微生物的扩散生态学中起着关键作用。由于生物气溶胶在环境中的浓度较低，因此收集足够的生物量进行分子方法研究具有挑战性。目前，用于分子生态学研究的生物气溶胶采集尚无标准化方法。每个研究都需要一个优化的过程，这极大地减缓了生物气溶胶科学的进展。在这里，我们评估了空气过滤和液体撞击法在一系列环境条件下对生物气溶胶的采样效果。我们还研究了采样基质、样品浓缩策略和采样持续时间对 DNA 产量的影响。使用聚碳酸酯过滤器进行空气过滤可获得最高的回收率，但由于撞击法的采样速度更快，我们建议将这种方法用于精细尺度的时间/空间生态研究。为了防止对革兰氏阳性菌回收的偏差，我们发现撞击法的基质应为磷酸盐缓冲盐水。从液体基质中浓缩生物气溶胶的最佳方法是离心。然而，我们还提出了一种使用注射器过滤器从撞击样品中快速回收生物气溶胶的方法，这种方法不会影响高通量测序方法中微生物多样性。最后，我们提供了一个资源，使分子生态学家能够为他们的特定研究问题选择最合适的采样策略。
