Occurrence of Lipoteichoic Acid in Oral Streptococci

Abstract

The heterogeneous bacterial group known as oral streptococci was screened for the presence of cellular polyglycerolphosphate-containing lipoteichoic acid. This compound was detected in phenol extracts of lyophilized cells by an immunoassay in which polyglycerolphosphate-specific monoclonal antibody was used. Polyglycerolphosphate-containing lipoteichoic acid occurred in all 86 strains of oral streptococci examined except the Streptococcus mitis and Streptococcus oralis strains. This confirms the findings of Rosan (B. The term lipoteichoic acid (LTA) has been used to describe a group of closely related macroamphiphiles which are synthesized and primarily located in the cytoplasmic membranes of various gram-positive bacteria (5, 48). Historically, LTA has been structurally characterized by an unbranched linear polymer of 1,3-linked glycerol phosphate residues covalently attached to a terminal hydrophobic region comprised of fatty acids. Variations may occur in the length of the polyglycerolphosphate (PGP) chain, which usually does not exceed 40 residues, in the presence of glycosyl substituents and D-alanine on C-2 of the glycerol moiety, and in the structure of the glycolipid anchor. Thus, it is now common to use the term LTAs to indicate this heterogeneity. For reviews see references 10 and 38.RosanRecently, Fischer (12) has redefined LTAs as macroamphiphiles that contain alditolphosphates as integral parts of the hydrophilic chain. This more liberal definition allows for the inclusion of compounds in which the repeating unit contains glycosyl residues. These polyglycosylalditolphosphate-containing LTAs are very much less common than the classic PGPcontaining LTAs (PGP-LTAs). The wider definition was thought to be necessary to distinguish LTAs from macroamphiphiles which do not contain phosphate residues as an integral part of the repeating structure of the polar moiety and which Fischer (12) refers to as lipoglycans.Not all gram-positive microorganisms synthesize a form of LTA in its broader sense, and current evidence suggests that the organisms in which it is not present instead elaborate a lipoglycan. This may imply that these two classes of compounds could have similar functions, although the nature of the functions is by no means clear. This division between LTA-and lipoglycan-producing microorganisms, as defined by Fischer (12), appears to follow the broad taxonomic line based on guanine-plus-cytosine (G+C) contents of DNAs in that LTA synthesis seems to occur predominantly in members of the low-G + C-content Clostridium-Bacillus branch of the grampositive eubacteria rather than in members of the high-G+C-content actinomycete branch as defined by Fox et al. (15). However, to date, only a relatively few species belonging to a small number of bacterial genera have been examined. Both PGP-and non-PGP-LTA-synthesizing species are represented within the oral streptococci, and since Schleifer et al. ( 3 9 , Ruhland and Fiedler (34), and, more recently, Sutcliffe (37) have suggested that LTAs may have value as c...

Blood-brain barrier invasion by group B Streptococcus depends upon proper cell-surface anchoring of lipoteichoic acid

“…To visualize glycolipids, we sprayed the samples with α-naphthol (3.2%) in methanol-H2SO4-H2O (25:3:2, vol/vol/vol) and heated the plate at 110°C for 5-10 minutes. An LTA ELISA was developed using a mAb against LTA, IgG3 clone 55 (Hycult Biotechnology), originally derived from the splenocytes of mice challenged with Streptococcus sobrinus (20) and recognizing the common polyglycerol backbone of LTA that is shared by a large number of streptococcal and staphylococcal isolates (59). Briefly, 100 µl of GBS supernatants from culture in THB or whole GBS cells washed several times and resuspended in THB were added to 96-well polystyrene plates (Immulon 4, Dynatech Laboratories) and incubated overnight at 4°C.…”

Nisin Resistance of Streptococcus bovis

“…Lipoteichoic acid (LTA) was extracted from cells by using hot aqueous phenol (11,30). Cultures (1 liter) were centrifuged (10,000 ϫ g, 15 min, 25°C), washed in phosphate buffer (10 mM Na 2 HPO 4 and 1 mM MgCl 2 [pH 7.5]), and concentrated to approximately 0.15 g of cells/ml.…”

A Continuum of Anionic Charge: Structures and Functions ofd-Alanyl-Teichoic Acids in Gram-Positive Bacteria

“…Type II LTA has a -GalGal-Gro-P-repeating unit, while type III LTA has a -Gal-Gro-P-repeating unit (160). Type I LTA occurs in 84 of 86 strains of oral streptococci (the exceptions are Streptococcus mitis and Streptococcus oralis) (221). Streptococcus sp.…”