Functional characterization of the HMP-P synthase of Legionella pneumophila (Lpg1565).

ABSTRACT: The production of the pyrimidine moiety in thiamine synthesis, 2-methyl-4-amino-5-hydroxymethylpyrimidine phosphate (HMP-P), has been described to proceed through the Thi5-dependent pathway in Saccharomyces cerevisiae and other yeast. Previous work found that ScThi5 functioned poorly in a heterologous context. Here we report a bacterial ortholog to the yeast HMP-P synthase (Thi5) was necessary for HMP synthesis in Legionella pneumophila. Unlike ScThi5, LpThi5 functioned in vivo in Salmonella enterica under multiple growth conditions. The protein LpThi5 is a dimer that binds pyridoxal-5'-phosphate (PLP), apparently without a solvent-exposed Schiff base. A small percentage of LpThi5 protein co-purifies with a bound molecule that can be converted to HMP. Analysis of variant proteins both in v

SUBMITTER: Paxhia MD 

PROVIDER: S-EPMC8026769 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature