Lipopolysaccharide Is a 4-Aminoarabinose Donor to Exogenous Polyisoprenyl Phosphates through the Reverse Reaction of the Enzyme ArnT.

ABSTRACT: Modification of the lipid A portion of LPS with cationic monosaccharides provides resistance to polymyxins, which are often employed as a last resort to treat multidrug-resistant bacterial infections. Here, we describe the use of fluorescent polyisoprenoids, liquid chromatography-mass spectrometry, and bacterial genetics to probe the activity of membrane-localized proteins that utilize the 55-carbon lipid carrier bactoprenyl phosphate (BP). We have discovered that a substantial background reaction occurs when B-strain E. coli cell membrane fractions are supplemented with exogenous BP. This reaction involves proteins associated with the arn operon, which is necessary for the covalent modification of lipid A with the cationic 4-aminoarabinose (Ara4N). Using a series of arn</

SUBMITTER: Scarbrough BA 

PROVIDER: S-EPMC8495848 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature