Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, WV, USA.
Health Effect Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, USA.
Microbiome. 2021 Jan 20;9(1):15. doi: 10.1186/s40168-020-00954-2.
Characterizing indoor microbial communities using molecular methods provides insight into bacterial assemblages present in environments that can influence occupants' health. We conducted an environmental assessment as part of an epidemiologic study of 50 elementary schools in a large city in the northeastern USA. We vacuumed dust from the edges of the floor in 500 classrooms accounting for 499 processed dust aliquots for 16S Illumina MiSeq sequencing to characterize bacterial assemblages. DNA sequences were organized into operational taxonomic units (OTUs) and identified using a database derived from the National Center for Biotechnology Information. Bacterial diversity and ecological analyses were performed at the genus level. We identified 29 phyla, 57 classes, 148 orders, 320 families, 1193 genera, and 2045 species in 3073 OTUs. The number of genera per school ranged from 470 to 705. The phylum Proteobacteria was richest of all while Firmicutes was most abundant. The most abundant order included Lactobacillales, Spirulinales, and Clostridiales. Halospirulina was the most abundant genus, which has never been reported from any school studies before. Gram-negative bacteria were more abundant and richer (relative abundance = 0.53; 1632 OTUs) than gram-positive bacteria (0.47; 1441). Outdoor environment-associated genera were identified in greater abundance in the classrooms, in contrast to homes where human-associated bacteria are typically more abundant. Effects of school location, degree of water damage, building condition, number of students, air temperature and humidity, floor material, and classroom's floor level on the bacterial richness or community composition were statistically significant but subtle, indicating relative stability of classroom microbiome from environmental stress. Our study indicates that classroom floor dust had a characteristic bacterial community that is different from typical house dust represented by more gram-positive and human-associated bacteria. Health implications of exposure to the microbiomes in classroom floor dust may be different from those in homes for school staff and students. Video abstract.
采用分子方法描述室内微生物群落，有助于了解环境中存在的细菌组合，这些组合可能会影响居住者的健康。我们在美国东北部一个大城市的 50 所小学进行了一项环境评估，作为一项对这些小学的流行病学研究的一部分。我们使用真空吸尘器从 500 间教室的地板边缘收集灰尘，共采集了 499 份处理过的灰尘样品，用于 16S Illumina MiSeq 测序，以描述细菌组合。DNA 序列被组织成操作分类单元（OTUs），并使用从国家生物技术信息中心衍生的数据库进行鉴定。在属水平上进行了细菌多样性和生态分析。我们在 3073 个 OTUs 中鉴定出 29 个门、57 个纲、148 个目、320 个科、1193 个属和 2045 个种。每所学校的属数量范围从 470 到 705 个。所有门中，厚壁菌门（Proteobacteria）最丰富，而 Firmicutes 最丰富。最丰富的目包括乳杆菌目（Lactobacillales）、螺旋菌目（Spirulinales）和梭菌目（Clostridiales）。盐螺旋菌属（Halospirulina）是最丰富的属，以前从未在任何学校研究中报道过。革兰氏阴性菌比革兰氏阳性菌更丰富和丰富（相对丰度=0.53；1632 OTUs）。与通常在家庭中更丰富的人类相关细菌相比，与室外环境相关的细菌在教室里的丰度更高。学校位置、水损害程度、建筑状况、学生人数、空气温度和湿度、地板材料以及教室地板高度对细菌丰富度或群落组成的影响具有统计学意义，但很细微，表明教室微生物组从环境压力下相对稳定。我们的研究表明，教室地板灰尘具有不同于典型房屋灰尘的特征细菌群落，典型房屋灰尘代表更多的革兰氏阳性菌和与人类相关的细菌。暴露于教室地板灰尘微生物组可能会对学校工作人员和学生的健康产生不同于家庭的影响。视频摘要。
