This enzyme in the enteric bacteria also possesses chorismate mutase activity and converts chorismate into prephenate. In microorganisms PDT is involved in the terminal pathway of the biosynthesis of phenylalanine. In some bacteria such as Escherichia coli PDT is part of a bifunctional enzyme (P-protein) that also catalyzes the transformation of chorismate into prephenate (chorismate mutase) while in other bacteria it is a monofunctional enzyme. The sequence of monofunctional PDT align well with the C-terminal part of that of P-proteins.

As signature patterns for PDT it has been selected two conserved regions. The first region contains a conserved threonine which has been said to be essential for the activity of the enzyme in Escherichia coli. The second region includes a conserved glutamate. Both regions are in the C-terminal part of PDT.
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