P5/P7 Flowcell Oligos

[jlove]

I apologize if this has been hashed out already, but I cannot seem to find any definitive documentation which describes whether the flowcell oligos are P5 and P7, or the complements. I know Illumina considers this information proprietary so it's not immediately obvious to me. I am wondering whether or not an excess of free P5 and P7 custom PCR primer (not dimer) would bind to the flowcell. I understand why dimers (which amplify and thus contain both P5/complement to P5, etc) would bind to the flowcell, but what about just these oligos?

My primers are:
SLXP5_PCR - AATGATACGGCGACCACCGAG
SLXP7_PCR - CAAGCAGAAGACGGCATACGAG

Anybody have a good, clear resource on this?

Thanks in advance!

[nucacidhunter]

Those oligos will not bind to flow cell oligo lawn but may bind to library strands reducing their effective concentration resulting in under clustering. Flow cell oligos for SE and PE flow cells are as following:

PE: 5’-PS-TTTTTTTTTT---------AATGATACGGCGACCACCGAGAUCTACAC-3’
SE: 5’-PS-TTTTTTTTTT-(diol)3-AATGATACGGCGACCACCGA-3

PE: 5’-PS-TTTTTTTTTTCAAGCAGAAGACGGCATACGAGoxoAT-3’
SE: 5’-PS-TTTTTTTTTTCAAGCAGAAGACGGCATACGA-3

[jlove]

This is very handy, thank you! May I ask how you figured out these sequences?
Jen

Those oligos will not bind to flow cell oligo lawn but may bind to library strands reducing their effective concentration resulting in under clustering. Flow cell oligos for SE and PE flow cells are as following:

PE: 5’-PS-TTTTTTTTTT---------AATGATACGGCGACCACCGAGAUCTACAC-3’
SE: 5’-PS-TTTTTTTTTT-(diol)3-AATGATACGGCGACCACCGA-3

PE: 5’-PS-TTTTTTTTTTCAAGCAGAAGACGGCATACGAGoxoAT-3’
SE: 5’-PS-TTTTTTTTTTCAAGCAGAAGACGGCATACGA-3

[nucacidhunter]

I have got it somewhere from a google search years ago, so the base modification may not be applicable to two colour chemistry or patterned flow cells. I think the sequences are still the same as old and new adapters share flow cell binding motives and when library fragments are shorter than cycle number a long stretch of A after adapter sequences are observed that are complementary to T homopolymer.

[darklight]

This is very handy, thank you! May I ask how you figured out these sequences?
Jen

This is very helpful. May I ask what does oxo stand for in the sequence?

[nucacidhunter]

I is oxoadenine (oxoA).

[darklight]

I is oxoadenine (oxoA).

Thank you!