Crystal structure of imidazole glycerol phosphate synthase: a tunnel through a (beta/alpha)8 barrel joins two active sites.
Chaudhuri, B.N., Lange, S.C., Myers, R.S., Chittur, S.V., Davisson, V.J., Smith, J.L.(2001) Structure 9: 987-997
- PubMed: 11591353 
- Primary Citation of Related Structures:  
1JVN - PubMed Abstract: 
Imidazole glycerol phosphate synthase catalyzes a two-step reaction of histidine biosynthesis at the bifurcation point with the purine de novo pathway. The enzyme is a new example of intermediate channeling by glutamine amidotransferases in which ammonia generated by hydrolysis of glutamine is channeled to a second active site where it acts as a nucleophile. In this case, ammonia reacts in a cyclase domain to produce imidazole glycerol phosphate and an intermediate of purine biosynthesis. The enzyme is also a potential target for drug and herbicide development since the histidine pathway does not occur in mammals.
Organizational Affiliation: 
Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.