Providing sample metadata
Entering sample metadata starts with providing basic details which are common to all your samples (Figure 8).
Figure 8 Entering metagenomic sample metadata.
- You will then be asked for the ‘Organism details’ related to your sample(s) - this is where you will indicate that they are metagenomic samples. Use the text search box to look for the metagenome taxonomy identifier related to your sample (Figure 8). NB: this field has to be filled even if your samples are not host-associated.
- For host-associated samples, do not enter the host organism but instead use the corresponding metagenome (e.g. 'human metagenome' for human metagenomic samples). For non-host-associated samples, there are defined metagenomes for most cases (e.g.:'soil metagenome', 'marine metagenome', 'freshwater metagenome', 'air metagenome' or simply 'metagenome').
- Finally, in the bottom right-hand corner of the page, you can provide the metadata relevant to the checklist you chose - mandatory fields are labelled with a red icon. You can expand each section by clicking on the ‘+’ sign in front or using the ‘Expand’ button.
NB: To ensure metadata are consistent, drop-down menus are provided where appropriate.
- Once you have filled in the checklist attributes, click 'Next' to go to the samples page. You can add as many samples as you like. Each one will require a unique sample title. The checklist metadata will be automatically associated with all these samples. You can edit the attributes for a particular sample on this page by selecting the corresponding sample checkbox.
- To make this process quicker, particularly if you have a lot of samples, ENA Webin allows you to download the attributes for all the samples in a tab-separated file. The file can easily be edited in software tools such as Excel and LibreOffice Calc. After editing, you can upload it back into ENA by clicking 'Previous' - this takes you back to the GSC MIxS checklist (Figure 7). Be aware that the date format may have been altered if you used Excel.
- Once you have updated the metadata for your samples, click 'Next' to associate your samples to your sequencing run data.