A Server Program for Hydrogen Exchange Rate Estimation


Neither the author of this program, Yu-Zhu Zhang, nor Fox Chase Cancer Center will be responsible for any damage that may result in from using this program. The author retains the right to modify the program without notice to any user.

If you use SPHERE to produce data for publication, Please advertise this page and reference ref. 1 on the SPHERE help page, where an early version of the Fortran Code for this program can be found. Also, I highly recomment referencing ref. 2 on the SPHERE help page where most of the information this program based on can be found.

Exchange in: D2O H2O pH meter reading: Temperature: oC
Reference Data from: Poly D-L Alanine Alanine in Oligo-peptide
Are the terminals blocked? N-Term: Yes No C-Term: Yes No

Default pKa

His: Glu: Asp: N-term.: C-term.:

Default activation energies Eas, (kcal/mol):

Acid EaH: Base EaOH: General EaG:
Are all cysteines involved in disulfide bonds? Yes No

If not, Type in the residue number of the reduced Cysteine(s), separated by a space:

Are there any cis Proline(s) in the structure? Yes No

If yes, Type in the residue number of the cis Proline(s), separated by a space:


Enter your sequence below (copy & paste):

Input query format
In the case of a PDB file of a dimer, etc.,
how many residues are in a monomer?

Include catalytic constants in the output? No Yes

To execute the query, press this button:

To clear the form, press this button:


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