Supplementary Methods

Supplementary
Table 1 The amount and percentage of contaminant sequences in the
negative control that passed through quality filtering and clustered into
operational taxonomic units (OTUs). The negative control contained trace
contaminants from nine of the 16 mock community members. This is presumably
due to cross-contamination during PCR and library preparation steps, despite
surface sterilization and stringency in protocols.

Supplementary Table 2 Amount of Operational Taxonomic Units (OTUs)
before and after filtering. For the mock libraries (A, B, and C). OTUs that
were chimeric were removed, and OTUs that matched ≤95% to one of the mock
community members were considered to be a weak consensus match and were also
removed.

补充表1：在阴性对照中，经过质量过滤并聚类成操作分类单元（OTU）的污染物序列的数量及百分比。阴性对照中含有来自16个模拟群落成员中的9个成员的微量污染物。这可能是由于在聚合酶链反应和文库制备步骤中存在交叉污染，尽管实施了表面灭菌和严格的操作规程。