The GalF protein of Escherichia coli is not a UDP-glucose pyrophosphorylase but interacts with the GalU protein possibly to regulate cellular levels of UDP-glucose

Molecular Microbiology
C L Marolda, M A Valvano

Abstract

We report the functional characterization of the galF gene of strain VW187 (Escherichia coli O7:K1), which encodes a polypeptide displaying structural features common to bacterial UDP-glucose pyrophosphorylases, including the E. coli GalU protein. These enzymes catalyse a reversible reaction converting UTP and glucose-1-phosphate into UDP-glucose and PPi. We show that, although the GalF protein is expressed in vivo, GalF-expressing plasmids cannot complement the phenotype of a galU mutant and extracts from this mutant which only produces GalF are enzymatically inactive. In contrast, the presence of GalU and GalF proteins in the same cell-free extract caused a significant reduction in the rate of pyrophosphorolysis (conversion of UDP-glucose into glucose-1-phosphate) but no significant effect on the kinetics of synthesis of UDP-glucose. The presence of GalF also increased the thermal stability of the enzyme in vitro. The effect of GalF in the biochemical properties of the UDP-glucose pyrophosphorylase required the co-synthesis of GalF and GalU, suggesting that they could interact as components of the oligomeric enzyme. The physical interaction of GalU and GalF was demonstrated in vivo by the co-expression of both proteins as fus...Continue Reading

Citations

Mar 17, 2004·Plant Physiology·Leszek A KleczkowskiHenrik Johansson
Apr 7, 2010·Applied and Environmental Microbiology·Henrike NiederholtmeyerJeffrey C Way
Dec 1, 2015·Frontiers in Microbiology·Ana C EbrechtMiguel A Ballicora
Aug 6, 2013·Applied and Environmental Microbiology·Revathy Ramachandran, Ann M Stevens
Oct 24, 2019·Environmental Microbiology Reports·Buddhie S NanayakkaraDavid M Gordon
Sep 21, 2018·Frontiers in Microbiology·Susan HarrisDavid G E Smith
Mar 28, 2019·MBio·Akanksha NigamHanna Engelberg-Kulka
Jun 5, 1998·Microbiology·Yoshihisa YamashitaToshihiko Koga
Sep 8, 1999·Microbiology and Molecular Biology Reviews : MMBR·H L RocchettaJ S Lam
Sep 8, 1998·Microbiology and Molecular Biology Reviews : MMBR·M K Berlyn

❮ Previous
Next ❯

Related Concepts

Related Feeds

Bacterial Respiration

This feed focuses on cellular respiration in bacteria, known as bacterial respiration. Discover the latest research here.