tryptophan mutants

[Kimberly Gilbride]

I am putting together a few genetics labs for a general microbiology 
course and I was interested in doing a nutritional mutant experiment 
using typtophan mutants.  These are mutants that have mutations at each 
of the steps in the tryptophan biosynthesis pathway.  The mutants that I 
wanted to use are ATCC 23717, ATCC 23718, ATCC 23719 and ATCC 23720.  I 
contacted ATCC and apparently they no longer have these strains.  I was 
wondering if anyone has these mutants and are willing to share them with 
me or can suggest an alternative biosynthetic pathway with corresponind 
mutants that can be used for this type of experiment.  If you can help 
please contact me directly at my e-mail address, thank-you.

Kim Gilbride
Ryerson Polytechnic University
350 Victoria Street
Toronto, Canada, M5B 2K3
gilbride at acs.ryerson.ca