Design of targeted primers based on 16S rRNA sequences in meta-transcriptomic datasets and identification of a novel taxonomic group in the Asgard archaea

Table 2 Types of mismatches among primer sites meeting the screening criteria

Primer	OTU	Mismatch type	OTU size	SILVA_Tax	NCBI_Tax
8F	OTU1	==G==A====A=========	49	Unclassified	Planctomycete
	OTU2	==G==A====A=========	33	Unclassified	Planctomycete
	OTU3	==G==A====A=========	34	Unclassified	Planctomycete
	OTU4	==G==A====A=C=======	11	Unclassified	Planctomycete
	OTU5	==G==A=====T========	10	Unclassified	Planctomycete
	OTU6	==G==A====A=C=======	10	Unclassified	Planctomycete
Arch21F	OTU7	C==T=============A==	69	Unclassified	Crenoarchaeota
	OTU8 (Type B)	=====T=C=======A====	25	Unclassified	Unclassified
	OTU9	=A=T=============A==	24	Unclassified	Euryarchaeota
	OTU10	C===A===========T===	10	Unclassified	Euryarchaeota
	OTU11 (Type A)	C==TA===========TA==	12	Unclassified	Unclassified

Evaluation of universal primers for mudflat meta-transcriptomic SSU rRNA sequences [26]. Screening criteria: the sequences of this OTU are taxonomically unclassified at the domain or/and phylum level, primer-binding regions in each sequence of this OTU are complete and the mismatched bases with the universal primer ≥3, and the sequence number in the OTU ≥10. OTUs identified in unclassified phyla with both SILVA_123 and NCBI BLAST are shown in boldface

ISSN: 1471-2180