Abstract
Bacterial lipoproteins comprise a subset of membrane proteins with a lipid-modified cysteine residue at their amino termini through which they are anchored to the membrane. In Gram-negative bacteria, lipoproteins are localized on either the inner or the outer membrane. The Lol system is responsible for the transport of lipoproteins to the outer membrane.
The Lol system comprises an inner-membrane ABC transporter LolCDE complex, a periplasmic carrier protein, LolA, and an outer membrane receptor protein, LolB. Lipoproteins are synthesized as precursors in the cytosol and then translocated across the inner membrane by the Sec translocon to the outer leaflet of the inner membrane, where lipoprotein precursors are processed to mature lipoproteins. The LolCDE complex then mediates the release of outer membrane-specific lipoproteins from the inner membrane while the inner membrane-specific lipoproteins possessing Asp at position 2 are not released by LolCDE because it functions as a LolCDE avoidance signal, causing the retention of these lipoproteins in the inner membrane. A water-soluble lipoprotein–LolA complex is formed as a result of the release reaction mediated by LolCDE. This complex traverses the hydrophilic periplasm to reach the outer membrane, where LolB accepts a lipoprotein from LolA and then catalyzes its incorporation into the inner leaflet of the outer membrane.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsSpringer Nature is developing a new tool to find and evaluate Protocols. Learn more
References
Yokota, N., Kuroda, T., Matsuyama, S., and Tokuda, H. (1999) Characterization of the LolA-LolB system as the general lipoprotein localization mechanism of Escherichia coli. J. Biol. Chem. 274, 30995–30999.
Pugsley, A.P., d’Enfert, C., Reyss, I., and Kornacker, M.G. (1990) Genetics of extracellular protein secretion by Gram-negative bacteria. Annu. Rev. Genet. 24, 67–90.
Tajima, T., Yokota, N., Matsuyama, S., and Tokuda, H. (1998) Genetic analyses of the in vivo function of LolA, a periplasmic chaperone involved in the outer membrane localization of Escherichia coli lipoproteins. FEBS Lett. 439, 51–54.
Narita, S., Tanaka, K., Matsuyama, S., and Tokuda, H. (2002) Disruption of lolCDE, encoding an ATP-binding cassette transporter, is lethal for Escherichia coli and prevents release of lipoproteins from the inner membrane. J. Bacteriol. 184, 1417–1422.
Tanaka, K., Matsuyama, S., and Tokuda, H. (2001) Deletion of lolB, encoding an outer membrane lipoprotein, is lethal for Escherichia coli and causes accumulation of lipoprotein localization intermediates in the periplasm. J. Bacteriol. 183, 6538–6542.
Miyamoto, A., Matsuyama, S., and Tokuda, H. (2001) Mutant of LolA, a lipoprotein-specific molecular chaperone of Escherichia coli, defective in the transfer of lipoproteins to LolB. Biochem. Biophys. Res Commun. 287, 1125–1128.
Ito, Y., Kanamaru, K., Taniguchi, N., Miyamoto, S., and Tokuda, H. (2006) A novel ligand-bound ABC transporter, LoICDE, provides insights into the molecular mechanisms underlying membrane detachment of bacterial lipoproteins. Mol. Microbiol. 62, 1064–1075.
Mizuno, T. (1979) A novel peptidoglycan-associated lipoprotein found in the cell envelope of Pseudomonas aeruginosa and Escherichia coli. J. Biochem. (Tokyo) 86, 991–1000.
Kaback, H. R. (1971) Bacterial membranes. Methods Enzymol. 22, 99–120.
Matsuyama, S., Tajima, T., and Tokuda, H. (1995) A novel periplasmic carrier protein involved in the sorting and transport of Escherichia coli lipoproteins destined for the outer membrane. EMBO J. 14, 3365–3372.
Matsuyama, S., Yokota, N., and Tokuda, H. (1997) A novel outer membrane lipoprotein, LolB (HemM), involved in the LolA (p20)-dependent localization of lipoproteins to the outer membrane of Escherichia coli. EMBO J. 16, 6947–6955.
Hussain, M., Ichihara, S. and Mizushima, S. (1980) Accumulation of glyceride-containing precursor of the outer membrane lipoprotein in the cytoplasmic membrane of Escherichia coli treated with globomycin. J. Biol. Chem. 255, 3707–3712.
Laemmli, U. K. (1970) Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 227, 680–685.
Ito, H., Ura, A., Oyamada, Y., Yoshida, H., Yamagishi, J., Narita, S., Matsuyama, S., and Tokuda, H. (2007) A new screening method to identify inhibitors of the Lol (localization of lipoproteins) system, a novel antibacterial target. Microbiol. Immunol. 51, 263–270.
Acknowledgements
We wish to thank Rika Ishihara for the help in the preparation of this chapter. The work described here was supported by grants to H. T. from the Ministry of Education, Science, Sports, and Culture of Japan.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2010 Springer Science+Business Media, LLC
About this protocol
Cite this protocol
Narita, Si., Tokuda, H. (2010). Sorting of Bacterial Lipoproteins to the Outer Membrane by the Lol System. In: Economou, A. (eds) Protein Secretion. Methods in Molecular Biology, vol 619. Humana Press. https://doi.org/10.1007/978-1-60327-412-8_7
Download citation
DOI: https://doi.org/10.1007/978-1-60327-412-8_7
Published:
Publisher Name: Humana Press
Print ISBN: 978-1-60327-167-7
Online ISBN: 978-1-60327-412-8
eBook Packages: Springer Protocols