[ccp4bb] Off-topic: chemical modification on thiol groups

[Remy Loris]

I am looking for a reagent (and vendor) that will irreversible put a 
raher bulky substituent on a free SH group and that does not react with 
free amines (or other potential reactive groups present on a protein 
surface). The connection with crystallography is that it is required for 
an experiment asked by a referee necessary to confirms or reject a 
hypothesis that results from a crystal structure. For this experiment it 
is essential that the reaction is not reversible (so no S-S bond 
formation).

Remy Loris
Vrije Universiteit Brussel