CLOTU: An online pipeline for processing and clustering of 454 amplicon reads into OTUs followed by taxonomic annotation

Table 1 Result summary of ITS data analyses (Filtering step)

	No error allowed			Two base pair error allowed
A NALYSIS I	Considered	Accepted	Rejected	Considered	Accepted	Rejected
Tags	12486	12015	471	12486	12015	471
Primers (FP+RP)	12015	3285	8730	12015	3656	8359
Incompatible tags combination	3285	3284	1	3656	3655	1
Ns	3283	3034	250	3655	3399	256
Length (<150)	3034	3033	1	3399	3398	1
Identical sequences	3033	339	2694	3398	571	2827
A NALYSIS II
Tags	12486	12015	471	12486	12015	471
Primers (FP)	12015	11753	262	12015	11988	27
Ns	11753	10622	1132	11988	10827	1161
Length (<150)	10622	10430	192	10827	10614	213
Identical sequences	10430	2389	8041	10614	2549	8065

Table providing detailed statistics about the various filtering steps used on the example datasets. In analysis I both forward and reverse primers were searched for in the sequences (with zero or two mismatches in forward and reverse primers). In analysis II, only the forward primer was searched for (with zero or two mismatches in forward primer only). The filtering in analysis I resulted in 339 and 571 unique sequences while analysis II resulted in 2389 and 2549 unique sequences.

ISSN: 1471-2105