Crystal Structure, Steady-State, and Pre-Steady-State Kinetics of Acinetobacter baumannii ATP Phosphoribosyltransferase.

ABSTRACT: The first step of histidine biosynthesis in Acinetobacter baumannii, the condensation of ATP and 5-phospho-α-d-ribosyl-1-pyrophosphate to produce N¹-(5-phospho-β-d-ribosyl)-ATP (PRATP) and pyrophosphate, is catalyzed by the hetero-octameric enzyme ATP phosphoribosyltransferase, a promising target for antibiotic design. The catalytic subunit, HisG_S, is allosterically activated upon binding of the regulatory subunit, HisZ, to form the hetero-octameric holoenzyme (ATPPRT), leading to a large increase in k_cat. Here, we present the crystal structure of ATPPRT, along with kinetic investigations of the rate-limiting steps governing catalysis in the nonactivated (HisG_S) and activated (ATPPRT) forms of the enzyme. A pH-rate profile sh

SUBMITTER: Read BJ 

PROVIDER: S-EPMC10795190 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature