Converts a FASTA or FASTQ file with usearch-compatible sample identifiers to QIIME-compatible format.
QIIME embeds sample identifiers into sequence labels using the following rules:
A label starts with the sample name followed by an underscore (_) and a read number 1, 2, 3 etc.
The read number is optionally followed by white space and other information which is usually (always?) ignored by the QIIME scripts.
Only alphanumeric and perdiod (.) characters are allowed in sample names.
The fastx2qiime command converts to QIIME format by finding the sample identifier and appending an underscore and a sequence number. All other information in the label is discarded. Any character in the sample identifier which is not alphameric or a period is replaced by a period.
Input can be in FASTA or FASTQ format. The output filename is specified by -fastqout (FASTQ format) and / or -fastaout (FASTA format). You cannot create FASTQ output from FASTA input.
usearch -fastx2qiime reads.fastq -fastaout reads_qiime.fa