HTTM : Illumina libraries
Antoine Champie, Amélie De Grandmaison
Abstract
Part three of the HTTM protocol. A low-cost and high-throughput Tn-seq protocol.
This part cover the preparation of Illumina sequencing libraries form genomic DNA.
Before start
All steps and master mixes need to be kept on ice as much as possible. Thermocyclers need to be cooled at 4 ° C before inserting sample plate.
Steps
Libraries
Transfer2.5µL of DNA from the DNA extraction plate to a new PCR plate.
Prepare a fragmentation master mix with :
| A | B |
|---|---|
| NEB Ultra II FS buffer | 77 µl |
| NEB Ultra II FS enzyme | 22 µl |
| Molecular grade water | 11 µl |
Add 1µL of the fragmentation master mix to each well.
Incubate in a thermocycler with the following protocol :
0h 15m 0sat37°C0h 30m 0sat65°C
Add 1µLof 4µM Nextera (NxT) adaptors to each well.
Prepare a ligation master mix with :
| A | B |
|---|---|
| NEB Ultra II ligation master mix | 377.4 µl |
| NEB Ultra II ligation enhancer | 12.1 µl |
Add 3.5µLof ligation master mix to each well.
Incubate in a thermocycler with the following protocol :
0h 30m 0sat20°C0h 10m 0sat65°C
Prepare a PCR master mix with :
| A | B |
|---|---|
| NxT_A primer 20 µM | 880 µl |
| Nxt_B primer 20 µM | 880 µl |
| Molecular grade water | 8360 µl |
| PCR Supermix 2X | 11000 µl |
Add 192µLof PCR master mix to each well.
Split the PCR reaction into 4 different plates (50µl per plate).
Incubate each plate in a thermocycler with the following cycles :
0h 0m 30sat98°C0h 0m 15sat98°C0h 0m 30sat72°C- Repeat from step 2 for 20~25 cycles*
0h 2m 0s72°C
Pool the 4 PCR replicates together in a PCR plate.
Transfer2µLof DNA from the pool plate to a new PCR plate.
Add 2µLof each barcoding primer to the DNA :
-
Nxt_i5_barcoding
-
Nxt_i7_barcoding
Prepare a PCR master mix with :
| A | B |
|---|---|
| Molecular grade water | 2090 µl |
| PCR supermix 2X | 2750 µl |
Add 44µL of the PCR master mix to each well of the plate.
Incubate in a thermocycler using the following protocol :
0h 0m 30sat98°C0h 0m 15sat98°C0h 1m 0sat72°C(no anneal step)- Repeat from step 2 for 5 cycles
0h 2m 0sat72°C
Pool together 2µL of each sample.
Purify with Ampure XP SPRI beads using a 0.8 ratio. Resuspend with50µL of molecular grade water.
Proceed with QC and sequencing.