Identification of a Specific Inhibitor of Human Scp1 Phosphatase Using the Phosphorylation Mimic Phage Display Method
Round 1
Reviewer 1 Report
In this manuscript, the authors reported a rapid and simple method to identify substrates of Ser/Thr phosphatases. They used PMPD method with BeF3- instead of AlF4− to identify novel substrate peptides that can bind to the catalytic pocket of Scp1. Three peptide sequences were identified as Scp1-binding candidates. This method may be useful to identify novel substrates and inhibitors of the FCP/SCP phosphatase family. Two comments were suggested to the authors.
1) Line 102 to line 106
It may be better to use a picture to explain how AlF4- or BeF3- connect with the residues AA in the enzyme's activity pocket.
2) The authors should explain why BeF3- is better to identify novel substrate in PMPD method. Line 111 to line 122, these are results of the research, they should be moved to the discussion.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Please find my comments about the results and the presentation below:
Figure 4 b: Please explain why there is a very large standard deviation in chart b? Materials and methods: Please describe in detail the conditions under which the HPLC analyzes were performed. Materials and methods:” After 7 min reaction, the reactions were quenched by adding 50 μL of stop solution (0.1 M Tris, 2% SDS).” Please change this sentence to remove the laboratory slang. What does it mean: The BeM12-1(1pT) peptide was added to reaction mixtures as the inhibitor at concentrations of 0, 10, 40 and 100 μ”? Line 479: The name of compounds should be written in small letter.Author Response
Please see the attachment.
Author Response File: Author Response.pdf
