Pseudomonas putida Tryptophan Synthetase: Partial Sequence of the α Subunit

Abstract

There is 50% identity in the sequences of the first 50 residues of the α chains of Escherichia coli and Pseudomonas putida . No deletions or additions of residues are found in this region, except for the N-terminal methionine residue which is missing in the polypeptide isolated from P. putida . Most of the residues which differ are chemically dissimilar, and half of them are specified by codons which differ by more than a single base. The two residues known by mutational analysis to be essential for catalysis in E. coli are conserved in P. putida . The potential taxonomic usefulness of information of this sort is analyzed.