USEARCH manual > algorithms > OTU clustering
SSU metagenomics

 
See also
 
OTU clustering
  What is an OTU?
 
Finding species in SSU reads
  SSU reference databases

Metagenomics using SSU rRNA
Next-generation sequencing allows high-throughput acquisition of nucleotide sequences for genes or regions for which universal PCR primers are available, i.e. primers that match a large majority of the species of interest. In microbial ecology, small subunit ribosomal RNA (SSU rRNA) genes are typically used: 16S for prokaryotes, ITS for fungi and 18S for eukaryotes. A typical metagenomics experiment generates thousands (pyrosequencing) to millions (Solexa/Illumina) of reads.