For the convenience of users, particularly for the vast majority of experimental scientists, a publicly accessible web-server for iPromoter-2L has been established. Moreover, to maximize users' convenience, given below a step-by-step guide on how to use it to get the desired results without the need to through the above mathematical details.

  Step 1. Open the web-server by clicking the link at http://bliulab.net/iPromoter-2L/ and you will see its top page of iPromoter-2L. Click on the ReadMe button to see a brief introduction about the server.

  Step 2. Either type or copy and paste the query sequences into the input box at the center of iPromoter-2L. You may also upload your input via the Browse button. The input sequence should be in the FASTA format. For the examples of sequences in FASTA format, click the Example button right above the input box.

  Step 3. Click on the Submit button to see the predicted results. The predicted results will be shown on the screen. For example, if using the query sequences in the Example window, you will see the following on your computer screen: (1) the 1st query sequence is of non-promoter sequences; (2) the 2nd query is of σ²⁴-promoter sequences; (3) the 3rd query sequence is of σ⁷⁰-promoter sequences. All these predicted results are fully consistent with experimental observations.

  Step 4. Click the on Supporting Information button to download the benchmark dataset used in this study.

  Step 5.Click on the Citation button to find the relevant papers that have played the key roles in developing the iPromoter-2L predictor.