RpoB subfamilies.

A Lek clustering method was applied to all RpoB superfamily members retrieved from the NRAA database, microbial genome projects, and the GOS data set. Clusters that contain only sequences from the GOS data set are noted as “From GOS only.”*Clusters 1, 9, 10, 11, 15, and 16 contain only sequence fragments from the GOS data set; though possibly novel they were omitted from further analysis.**Cluster 5 contains only two sequences. Though both are from the GOS (IDs 1096695464231 and 1096681823525) and may represent a novel RpoB subfamily, this group was excluded from further analysis because we restricted analyses to groups with three or more sequences.本研究采用Lek聚类法，对从NRAA数据库、微生物基因组计划及GOS数据集中检索得到的全部RpoB超家族（RpoB superfamily）成员进行聚类分析。仅包含GOS数据集序列的聚类被标注为"仅源自GOS数据集"。*聚类1、9、10、11、15及16仅包含GOS数据集的序列片段；尽管其可能为新型类群，但未被纳入后续分析。**聚类5仅包含两条序列。尽管这两条序列均来自GOS数据集（序列ID：1096695464231与1096681823525），且可能代表一个新型的RpoB亚家族，但由于本研究将分析范围限定为包含3条及以上序列的类群，因此该聚类被排除在后续分析之外。