Biological functions of sialic acid as a component of bacterial endotoxin

Bartłomiej Dudek; Jacek Rybka; Gabriela Bugla-Płoskońska; Agnieszka Korzeniowska-Kowal; Bożena Futoma-Kołoch; Aleksandra Pawlak; Andrzej Gamian

doi:10.3389/fmicb.2022.1028796

Biological functions of sialic acid as a component of bacterial endotoxin

Front Microbiol. 2022 Oct 20:13:1028796. doi: 10.3389/fmicb.2022.1028796. eCollection 2022.

Authors

Bartłomiej Dudek¹, Jacek Rybka², Gabriela Bugla-Płoskońska¹, Agnieszka Korzeniowska-Kowal², Bożena Futoma-Kołoch¹, Aleksandra Pawlak¹, Andrzej Gamian²

Affiliations

¹ Department of Microbiology, University of Wrocław, Wrocław, Poland.
² Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.

Abstract

Lipopolysaccharide (endotoxin, LPS) is an important Gram-negative bacteria antigen. LPS of some bacteria contains sialic acid (Neu5Ac) as a component of O-antigen (O-Ag), in this review we present an overview of bacteria in which the presence of Neu5Ac has been confirmed in their outer envelope and the possible ways that bacteria can acquire Neu5Ac. We explain the role of Neu5Ac in bacterial pathogenesis, and also involvement of Neu5Ac in bacterial evading the host innate immunity response and molecular mimicry phenomenon. We also highlight the role of sialic acid in the mechanism of bacterial resistance to action of serum complement. Despite a number of studies on involvement of Neu5Ac in bacterial pathogenesis many aspects of this phenomenon are still not understood.

Keywords: Gram-negative bacteria; O-antigen; lipopolysaccharide; molecular mimicry; outer membrane; pathogenesis; sialic acid.

Publication types

Review