This information is specific for the 16S Illumina Libraries. Multiplexed genome libraries should follow the information for the genome barcodes.
Outline:
In order to multiplex more than 96 samples into a lane, a forward barcode is required. This is because the reverse barcodes cost a lot of money to make, and you can get more bang for your buck using the same reverse barcodes again with a different forward barcode. The forward barcode is a 5 bp sequence before the U515 F primer sequence. The forward primer must also include homology to the second step forward primer sequence. The entire construct is depicted in Fig S1.pdf.
Forward Primer Barcode Sequences:
These are the forward barcode sequences that we currently have are here: Manually_copied_forward_barcodes.xls