Denitrification is an important global N cycle process. The gene encoding NosZ that converts nitrous oxide (N₂O) to N₂ has been widely used as a biomarker to study denitrifying communities. However, conventional PCR primers target a limited range of the genetically diverse Clade I nosZ, and the amplicons are too long for sequencing on current NGS platforms. To address these issues, we developed a new PCR primer set that amplifies a 355-bp region of Clade I nosZ and captures broader taxonomic coverage than conventional primers in in silico tests. When compared with the widely used nosZF_nosZR_Rich_2003 set using the same soil samples and the same sequencing depth, the new set retrieved genes from four times more unique species, with consistently higher general diversity-based metrics. The new primer set performed well with different sequencing platforms (Ion Torrent and Illumina), and among a wide variety of soils from polar to tropical, desert to agricultural, and surface to a very low biomass subsoil, with significant differences in denitrifying community diversity and composition. This new primer set for Clade I together with the primers recently reported for Clade II by Chee-Sanford et al. (J Microbiol Meth 172:105908, 2020) provides a more comprehensive assessment of denitrifier gene hosts, their ecological patterns, and the degree of novelty in retrieved gene sequences.

反硝化是重要的全球N循环过程。编码将一氧化二氮（N ₂ O）转化为N _2的NosZ的基因已被广泛用作研究反硝化群落的生物标记。然而，常规的PCR引物靶向有限范围的遗传多样性的Clade I nosZ，并且扩增子对于在当前的NGS平台上测序太长。为了解决这些问题，我们开发了一种新的PCR引物组，可扩增Clade I nosZ的355 bp区域并在计算机测试中获得比常规引物更广泛的分类学覆盖范围。与使用相同土壤样品和相同测序深度的广泛使用的nosZF_nosZR_Rich_2003组进行比较时，该新组从四倍于独特物种的基因中检索到基因，并始终具有更高的基于一般多样性的指标。新的引物组在不同的测序平台（离子激流和Illumina）以及从极地到热带，从沙漠到农业，从地表到非常低的生物量土壤的各种土壤中表现良好，在反硝化群落多样性和作品。这种新的Clade I引物以及Chee-Sanford等人最近报道的Clade II引物。（微生物微生物学杂志 172：105908，2020）对反硝化基因宿主，其生态模式以及检索到的基因序列的新颖程度进行了更全面的评估。