chemical analyses and qPCR
(1) Production of 15N-labeled N2 (i.e., 29N2 and 30N2), reduction of As(V) to As(III) and abundances of arrA and hzsB genes in soil slurry cultures amended with urea+As(V), urea or urea+As(V)+C2H2. (2) Proportions of hzsB genes in the fractions obtained in DNA-SIP. (3) Nucleic acid reads based on Prokar_16S and AMX_16S amplicons.
Steps to reproduce
All the raw amplicon sequencing data were analyzed with the Quantitative Insights Into Microbial Ecology (QIIME2, version 2020.2) toolkit as described previously. Briefly, sequences were qualified by removing the low-quality reads and chimera with the parameters as follows: --p-trim-left-f 0, --p-trim-left-r 184 for Prokar_16S and 293 for AMX_16S, --p-trunc-len-f 0, --p-trunc-len-r 161 for Prokar_16S and 259 for AMX_16S. The qualified reads were merged into amplicon sequence variants (ASVs) using DADA2. ASVs with proportion < 0.01% of total counts were eliminated before being assigned to taxonomy using the RDP classifier (version 16S rRNA training set 18, http://rdp.cme.msu.edu/classifier/classifier.jsp).