Key points are not available for this paper at this time.
A series of ten enzymes in Salmonella typhimurium convert the 5-carbon chain of phosphoribosyl pyrophosphate to the 5-carbon chain of histidine (Fig. 1). The pathway of histidine biosynthesis has no branches giving rise to other essential metabolites. Most of the intermediates of the pathway have been characterized and assays for 8 of the 10 enzymes are in routine use.
Ames et al. (Tue,) studied this question.