Structure and function of Listeria teichoic acids and their implications

Abstract

Teichoic acids (TAs) are the most abundant glycopolymers in the cell wall of Listeria, an opportunistic Gram‐positive pathogen that causes severe foodborne infections. Two different structural classes of Listeria TA exist: the polyribitolphosphate‐based wall teichoic acid (WTA) that is covalently anchored to the peptidoglycan, and the polyglycerolphosphate‐based lipoteichoic acid (LTA) that is tethered to the cytoplasmic membrane. While TA polymers govern many important physiological processes, the diverse glycosylation patterns of WTA result in a high degree of surface variation across the species and serovars of Listeria, which in turn bestows varying effects on fitness, biofilm formation, bacteriophage susceptibility and virulence. We review the advances made over the past two decades, and our current understanding of the relationship between TA structure and function. We describe the various types of TA that have been structurally determined to date, and discuss the genetic determinants known to be involved in TA glycosylation. We elaborate on surface proteins functionally related to TA decoration, as well as the molecular and analytical tools used to probe TAs. We anticipate that the growing knowledge of the Listeria surface chemistry will also be exploited to develop novel diagnostic and therapeutic strategies for this pathogen.

Reporter Phage-Based Detection of Bacterial Pathogens: Design Guidelines and Recent Developments

“…(B) Host specificity of phages is mediated by specialized receptor-binding proteins (RBPs) that provide equivalent binding capabilities as whole phages, but at a fraction of the size. Recently, RBPs have been applied in biosensors [47], ELISA-based assays [38,40], and for glycotyping Salmonella [39] and Listeria [32]. (C) Alternatively, cell wall-binding domains (CBDs) of phage endolysins have proven highly effective at detecting Gram-positive pathogens.…”

“…The alternative to whole-phage bio-probes is to use phage proteins that confer host binding ( Figure 1 B,C). For example, cell wall-binding domains (CBDs) of phage endolysins have been successfully used for detecting various Gram-positive bacteria, e.g., Listeria [ 32 , 33 ], Bacillus cereus [ 34 ], and Clostridium tyrobutyricum [ 35 ]. Phages recognize their bacterial hosts using specialized receptor-binding proteins (RBPs), identified as tail fibers and tailspikes, which initiate the attachment of the phage to specific receptors on the bacterial cell wall [ 36 , 37 ].…”

Bacteria elicit a phage tolerance response subsequent to infection of their neighbors

“…WTA polymers were found to be crucial surface components, required for invasion by manifold phages into Gram-positive bacteria [e.g. Bacilli, Staphylococci, Listeria (Habusha et al, 2019;Ingmer et al, 2019;Lindberg, 1973;Sumrall et al, 2020)]. SPP1, a double-stranded DNA (dsDNA) phage (44 kb) and a member of the Siphoviridae family, characterized by a long noncontractile tail (Alonso et al, 1997), initiates infection by reversible binding of the tail tip to polyglycosylated WTA (gWTA).…”

Glucose decoration on wall-teichoic acid is required for phage adsorption and InlB-mediated virulence in Listeria ivanovii

“…Beyond serving as the major antigenic determinants for serotyping, WTAs are involved in several key physiological functions, including maintaining osmotic pressure, antibiotic resistance, virulence, and interaction with host cells and bacteriophages (13)(14)(15)(16)(17)(18). WTAs consist of a single glycosylated glycerol-based linkage unit, and a chain of 20-30 repeating units which can vary in structure between individual strains (19).…”

“…Because these decorations appear to serve both as receptors for bacteriophage binding, as well as ligands for the surface-associated virulence factor InlB, it became evident that Listeria faces a tradeoff between maintaining virulence and developing bacteriophage resistance (18).…”