论文标题：Daylight exposure modulates bacterial communities associated with household dust

期刊：Microbiome

作者：Ashkaan K. Fahimipour, Erica M. Hartmann, Andrew Siemens, Jeff Kline, David A. Levin, Hannah Wilson, Clarisse M. Betancourt-Román, GZ Brown, Mark Fretz, Dale Northcutt, Kyla N. Siemens, Curtis Huttenhower, Jessica L. Green and Kevin Van Den Wymelenberg

发表时间：2018/10/18

数字识别码：10.1186/s40168-018-0559-4

原文链接：https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-018-0559-4?utm_source=WeChat&utm_medium=Website_linksSocial_media_organic&utm_content=CelZha-MixedBrand-multijournal-Multidisciplinary-China&utm_campaign=ORG_AWA_CZH_BMCWechat_dailyposts_blogs

微信链接：https://mp.weixin.qq.com/s/A1UCTTAZMARTAWlVE7Oxtg

原文作者：Ashkaan K. Fahimipour, Erica M. Hartmann, Andrew Siemens, Jeff Kline, David A. Levin, Hannah Wilson, Clarisse M. Betancourt-Román, GZ Brown, Mark Fretz, Dale Northcutt, Kyla N. Siemens, Curtis Huttenhower, Jessica L. Green and Kevin Van Den Wymelenberg

最近发表在Microbiome上的一项研究显示，让阳光透过窗子照进房间可以杀死生活在灰尘中的细菌。

让阳光照进室内。

图片来源：pixabay.com

美国俄勒冈大学的研究者们发现，在黑暗的房间中平均有12%的细菌存活且能够繁殖。与之形成对比的是，有阳光照射的房间里只有6.8%的细菌存活，UV照射过的细菌中只有6.1%仍具备繁殖能力。

研究的通讯作者Dr Fahimipour说：“人类大部分时间都在室内，这使得我们不可避免地暴露在携带各种细菌、甚至是致病菌的灰尘当中。因此了解我们居住建筑的特点会如何影响灰尘的生态环境以及这对我们的健康有何影响十分重要。”

黑暗中的灰尘会携带与呼吸系统疾病密切相关的微生物种类，而这些微生物在暴露于日光下的灰尘中含量很少。

作者们发现与黑暗中的灰尘相比，光下的灰尘中人类皮肤来源的细菌比例较小，室外空气来源的细菌比例较高。这可能表明日光会让室内灰尘的微生物组成更类似于户外发现的细菌群落。

研究人员制作了11个一模一样的气候控制微型房间，来模拟实际生活中的建筑，然后把住宅中收集的灰尘放入这些微型房间。作者对房间的窗户进行了3种处理，使它们分别可以透入可见光、紫外线或无法透光。90天之后，作者从每个环境中都收集了灰尘，并对其细菌组成、含量和繁殖能力（活力）进行了分析。

Dr Fahimipour说：“我们的研究支持了一个有百年历史的民间智慧，阳光有杀死灰尘颗粒上的微生物的潜力，但我们还需要更多的研究来理解阳光使灰尘上微生物组成发生变化的背后机理。我们希望随着进一步的了解，我们能为像学校、办公室、医院和住宅这样的建筑设计采光方案，以降低灰尘传播细菌导致感染的风险。”

作者提醒说，研究中使用的微型室内环境仅暴露于相对较窄范围的光线剂量下。虽然研究人选所选择的光剂量与大部分建筑中的光剂量相似，但是仍有许多建筑和地理特征会产生更低或更高的光剂量，可能还需要进一步的研究。

摘要：

Background

Microbial communities associated with indoor dust abound in the built environment. The transmission of sunlight through windows is a key building design consideration, but the effects of light exposure on dust communities remain unclear. We report results of an experiment and computational models designed to assess the effects of light exposure and wavelengths on the structure of the dust microbiome. Specifically, we placed household dust in replicate model “rooms” with windows that transmitted visible, ultraviolet, or no light and measured taxonomic compositions, absolute abundances, and viabilities of the resulting bacterial communities.

Results

Light exposure per se led to lower abundances of viable bacteria and communities that were compositionally distinct from dark rooms, suggesting preferential inactivation of some microbes over others under daylighting conditions. Differences between communities experiencing visible and ultraviolet light wavelengths were relatively minor, manifesting primarily in abundances of dead human-derived taxa. Daylighting was associated with the loss of a few numerically dominant groups of related microorganisms and apparent increases in the abundances of some rare groups, suggesting that a small number of microorganisms may have exhibited modest population growth under lighting conditions. Although biological processes like population growth on dust could have generated these patterns, we also present an alternate statistical explanation using sampling models from ecology; simulations indicate that artefactual, apparent increases in the abundances of very rare taxa may be a null expectation following the selective inactivation of dominant microorganisms in a community.

Conclusions

Our experimental and simulation-based results indicate that dust contains living bacterial taxa that can be inactivated following changes in local abiotic conditions and suggest that the bactericidal potential of ordinary window-filtered sunlight may be similar to ultraviolet wavelengths across dosages that are relevant to real buildings.

阅读论文全文请访问：

https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-018-0559-4?utm_source=WeChat&utm_medium=Website_linksSocial_media_organic&utm_content=CelZha-MixedBrand-multijournal-Multidisciplinary-China&utm_campaign=ORG_AWA_CZH_BMCWechat_dailyposts_blogs

期刊介绍:

The central purpose of Microbiome (https://microbiomejournal.biomedcentral.com/, 9.133 - 2-year Impact Factor, 10.903 - 5-year Impact Factor) is to unite investigators conducting microbiome research in environmental, agricultural, and biomedical arenas.

Topics broadly addressing the study of microbial communities, such as, microbial surveys, bioinformatics, meta-omics approaches and community/host interaction modeling will be considered for publication. Through this collection of literature Microbiome hopes to integrate researchers with common scientific objectives across a broad cross-section of sub-disciplines within microbial ecology.

（来源：科学网）