bd1. What to send
Purified phage DNA extracted from a single, well-characterised phage isolate. Host bacterial DNA in the sample reduces the useful data and makes assembly harder.
| Parameter | Requirement |
|---|---|
| Concentration | 20–50 ng/µL or more |
| Total DNA | At least 500 ng |
| A260/280 | 1.8–2.0 |
| A260/230 | 2.0 or higher |
| Integrity | Intact DNA, free from host and environmental DNA |
2. Preparation tips
- Start from a plaque-purified phage; confirm purity before DNA extraction.
- Use a high-titre, purified lysate. Treat the lysate with DNase I and RNase A before opening the capsids, to remove free host nucleic acids.
- Extract the phage DNA (for example proteinase K + SDS, then phenol–chloroform or a kit).
- Use nuclease-free tubes and reagents; avoid repeated freeze–thaw.
- Store DNA at −20 °C (or as advised) and ship cool.
3. Information to send with the sample
- Phage name (if known) and sample ID
- Host bacterial species (scientific name)
- NCBI taxonomy ID or RefSeq accession of the host or a related phage, if available
Host information helps us interpret the genome and choose references for comparison. Sequencing: Illumina NovaSeq 6000, PE150, over 300× coverage (about 3–5 Gb per sample).