Repository logo
 

Reconstitution of surface lipoprotein translocation through the Slam translocon.

Published version
Peer-reviewed

Type

Article

Change log

Authors

Hooda, Yogesh 
Li, Yuzi Raina 
Jagielnicki, Maciej 
Lai, Christine Chieh-Lin 

Abstract

Surface lipoproteins (SLPs) are peripherally attached to the outer leaflet of the outer membrane in many Gram-negative bacteria, playing significant roles in nutrient acquisition and immune evasion in the host. While the factors that are involved in the synthesis and delivery of SLPs in the inner membrane are well characterized, the molecular machinery required for the movement of SLPs to the surface are still not fully elucidated. In this study, we investigated the translocation of a SLP TbpB through a Slam1-dependent pathway. Using purified components, we developed an in vitro translocation assay where unfolded TbpB is transported through Slam1-containing proteoliposomes, confirming Slam1 as an outer membrane translocon. While looking to identify factors to increase translocation efficiency, we discovered the periplasmic chaperone Skp interacted with TbpB in the periplasm of Escherichia coli. The presence of Skp was found to increase the translocation efficiency of TbpB in the reconstituted translocation assays. A knockout of Skp in Neisseria meningitidis revealed that Skp is essential for functional translocation of TbpB to the bacterial surface. Taken together, we propose a pathway for surface destined lipoproteins, where Skp acts as a holdase for Slam-mediated TbpB translocation across the outer membrane.

Description

Keywords

E. coli, Gram negative, Neisseria, bacteria, infectious disease, membrane proteins, microbiology, protein translocation, surface lipoprotein, Bacterial Outer Membrane Proteins, Escherichia coli, Escherichia coli Proteins, Lipoproteins, Periplasm

Journal Title

Elife

Conference Name

Journal ISSN

2050-084X
2050-084X

Volume Title

11

Publisher

eLife Sciences Publications, Ltd
Sponsorship
Canadian Institutes of Health Research (PJT-148795)
CIHR (PJT-148795)