Header

UZH-Logo

Maintenance Infos

Solution structure and dynamics of LptE from Pseudomonas aeruginosa


Moehle, Kerstin; Kocherla, Harsha; Bacsa, Bernadett; Jurt, Simon; Zerbe, Katja; Robinson, John A; Zerbe, Oliver (2016). Solution structure and dynamics of LptE from Pseudomonas aeruginosa. Biochemistry, 55(1):2936-2943.

Abstract

LptE is an outer membrane (OM) lipoprotein found in Gram-negative bacteria, where it forms a complex with the β-barrel lipopolysaccharide(LPS) transporter LptD. The LptD/E complex plays a key role in OM biogenesis, by translocating newly synthesized LPS molecules from the periplasm into the external leaflet of the asymmetric OM during cell growth. The LptD/E complex in Pseudomonas aeruginosa (Pa) is a target for macrocyclic β-hairpin-shaped peptidomimetic antibiotics, which inhibit the transport of LPS to the cell surface. So far, the three-dimensional structure of the Pa LptD/E complex and the mode of interaction with these antibiotics are unknown. Here, we report the solution structure of a Pa LptE derivative lacking the N-terminal lipid membrane anchor, determined by multidimensional solution nuclear magnetic resonance (NMR)spectroscopy. The structure reveals a central five-stranded β-sheet against which pack a long C-terminal and a short N-terminal α-helix, as found in homologues of LptE from other Gram-negative bacteria. One unique feature is an extended C-terminal helix in Pa LptE, which in a model of the Pa LptD/E complex appears to be long enough to contact the periplasmic domain of LptD. Chemical shift mapping experiments suggest only weak interactions occur between LptE and the oligosaccharide chains of LPS. The NMR structure of Pa LptE will be valuable for more detailed structural studies of the LptD/E complex from P. aeruginosa.

Abstract

LptE is an outer membrane (OM) lipoprotein found in Gram-negative bacteria, where it forms a complex with the β-barrel lipopolysaccharide(LPS) transporter LptD. The LptD/E complex plays a key role in OM biogenesis, by translocating newly synthesized LPS molecules from the periplasm into the external leaflet of the asymmetric OM during cell growth. The LptD/E complex in Pseudomonas aeruginosa (Pa) is a target for macrocyclic β-hairpin-shaped peptidomimetic antibiotics, which inhibit the transport of LPS to the cell surface. So far, the three-dimensional structure of the Pa LptD/E complex and the mode of interaction with these antibiotics are unknown. Here, we report the solution structure of a Pa LptE derivative lacking the N-terminal lipid membrane anchor, determined by multidimensional solution nuclear magnetic resonance (NMR)spectroscopy. The structure reveals a central five-stranded β-sheet against which pack a long C-terminal and a short N-terminal α-helix, as found in homologues of LptE from other Gram-negative bacteria. One unique feature is an extended C-terminal helix in Pa LptE, which in a model of the Pa LptD/E complex appears to be long enough to contact the periplasmic domain of LptD. Chemical shift mapping experiments suggest only weak interactions occur between LptE and the oligosaccharide chains of LPS. The NMR structure of Pa LptE will be valuable for more detailed structural studies of the LptD/E complex from P. aeruginosa.

Statistics

Citations

1 citation in Web of Science®
1 citation in Scopus®
Google Scholar™

Altmetrics

Downloads

2 downloads since deposited on 31 May 2016
0 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Chemistry
Dewey Decimal Classification:540 Chemistry
Uncontrolled Keywords:LPS biosynthesis NMR structural biology
Language:English
Date:31 May 2016
Deposited On:31 May 2016 16:17
Last Modified:26 Feb 2017 08:42
Publisher:American Chemical Society (ACS)
ISSN:0006-2960
Funders:Swiss National Science Foundation
Publisher DOI:https://doi.org/10.1021/acs.biochem.6b00313
PubMed ID:27166502

Download