Inhibition of Oral Streptococci Growth Induced by the Complementary Action of Berberine Chloride and Antibacterial Compounds.

Synergistic interactions between natural bioactive compounds from medicinal plants and antibiotics may exhibit therapeutic benefits, acting against oral cariogenic and opportunistic pathogens. The aim of the presented work was to assess the antibacterial activity of berberine chloride (BECl) in light of the effect exerted by common antibiotics on selected reference strains of oral streptococci (OST), and to evaluate the magnitude of interactions. Three representative oral microorganisms were investigated: Streptococcus mutans ATCC 25175 (SM), S. sanguinis ATCC 10556 (SS), S. oralis ATCC 9811 (SO) and microdilution tests, along with disc diffusion assays were applied. Here, we report that growth (viability) of all oral streptococci was reduced by exposure to BECl and was dependent primarily on exposure/ incubation time. A minimum inhibitory concentrations (MIC) of BECl against OST ranged from 512 µg/mL (SS) to 1024 µg/mL (SM, SO). The most noticeable antibacterial effects were observed for S. sanguinis (MIC 512 µg/mL) and the most significant synergistic action was found for the combinations BECl-penicillin, BECl-clindamycin and BECl-erythromycin. The S. oralis reflects the highest MBC value as assessed by the AlamarBlue assay (2058 µg/mL). The synergy between berberine and common antibiotics demonstrates its potential use as a novel antibacterial tool for opportunistic infections and also provides a rational basis for the use of berberine as an oral hygiene measure.

Disease modifying effects of N-butyryl glucosamine in a streptococcal cell wall induced arthritis model in rats.

OBJECTIVE: To evaluate the effect of different doses of N-butyryl glucosamine (GlcNBu) on joint preservation and subchondral bone density and quality in a streptococcal cell wall (SCW) induced arthritis model in Lewis rats. METHODS: Chronic arthritis was induced in 36 female Lewis rats by a single intraperitoneal injection of SCW antigen. The 4 groups studied were: (1) no arthritis, no drug treatment; (2) arthritis, no drug treatment; (3) arthritis, oral GlcNBu 20 mg/kg/day; and (4) arthritis, oral GlcNBu 200 mg/kg/day. Inflammation (ankle swelling) was quantified throughout the clinical course; bone mineral density (BMD) was measured by dual-energy x-ray absorptiometry on dissected distal femurs and proximal tibiae, in user defined regions of interest. Qualitative and quantitative 3-D bone architecture changes were determined using microcomputerized tomography on the left tibiae. Subchondral plate thickness and trabecular bone connectivity were studied on the proximal tibia epiphyses from the central coronal sections of each scanned tibia. RESULTS: GlcNBu inhibited inflammatory ankle swelling at both 20 and 200 mg/kg/day, the latter being statistically significant, with an average reduction of 33%. GlcNBu preserved or enhanced BMD and bone connectivity and prevented further bone loss at both the high and the low dose. Comparisons of the isosurfaces and the architectural measures in the different groups showed that GlcNBu effectively protected the joint surfaces from further erosion in this model of chronic inflammatory arthritis. For some of the bone measurements, increasing doses of GlcNBu showed increasing protective effects, while for other measurements, effects were maximal at the lower dose. CONCLUSION: These data indicate that GlcNBu provides antiinflammatory and antierosive effects by preserving BMD, joint integrity, and bone architecture in involved joints of the SCW model.

Relationship of the cell wall composition of group H streptococci and Streptococcus sanguis to their serological properties.

Previous studies indicated the a antigen was widely distributed among strains of Streptococcus sanguis and the group H streptococci. The cell walls of strains containing this antigen had moderate to large quantities of rhamnose, small amounts of phosphorus, and little to no ribitol. The molar ratios of the peptidoglycan amino acids and hexosamines suggested a di-alanyl cross bridge. The homogeneity of the walls of these strains suggested that serological group H can be considered synonymous with S. sanguis. In contrast those strains that did not contain the a antigen had only small amounts of rhamnose in their cell walls, galactosamine and ribitol were always detected, and large quantitites of phosphorus were present. The molar ratios of peptidoglycan components in the latter strains suggested a direct alanyl-lysl cross bridge. Although many of these strains had been classified either as S. sanguis or group H streptococci because of minor serological cross-reactions and similar biochemical properties, the distinct differences between the composition of their cell walls and those of S. sanguis and group H streptococci indicate that they do not belong in this species or group. The cell walls of strains containing the a antigen are relatively homogeneous and therefore it is suggested that cells containing this antigen be considered Lancefield serological group H.

Filamentous capsulated streptococci from the human respiratory tract. II. Antigenic structure of provisional capsular types 89 and 83-89.

Two immunologically distinct polysaccharides have been isolated from the filamentous alpha-hemolytic streptococcus of provisional capsular type 89, recovered from the human respiratory tract. Chemical analyses indicate that the capsular polysaccharide consists of glucose, galactose, and a small amount of rhamnose, whereas the cell wall-associated polymer contains galactosamine, glucosamine, glucose, and phosphorus. Immunological studies suggest that the capsular polysaccharide is type specific and that the cell wall-associated carbohydrate, which cross-reacts with the C(8), or cell wall-like capsular polysaccharide of pneumococcus, may be group specific. A noncapsulated variant of the prototypic streptococcus of provisional type 89 was shown to possess the same cell wall-associated carbohydrate as the strain from which it was derived, but it proved to be poorly antigenic in rabbits. A filamentous capsulated streptococcus reacting with antisera to filamentous streptococci of both provisional capsular types 83 and 89 has been found to produce two capsular polysaccharides, each of which reacts with antibody to one of the aforementioned unitypic strains and represents an unusual binary capsulated streptococcus.

Filamentous capsulated streptococci from the human respiratory tract. I. Antigenic attributes of provisional capsular type 83 and its relationship to streptococci of so-called group M.

Two immunologically reactive polysaccharides have been isolated from the cell walls and from culture filtrates of a filamentous alpha-hemolytic streptococcus provisionally designated capsular type 83. Both polysaccharides were purified by diethylaminoethyl-cellulose chromatography. Analysis indicates that the capsular polysaccharide consists of galactose and phosphorus, whereas the cell wall polysaccharide contains galactosamine, glucosamine, glucose, and phosphorus. On the basis of immunochemical experiments, it is suggested that the capsular polysaccharide is composed of galactose-phosphate units with terminal galactose residues at the nonreducing end. It has also been found that the capsular antigen of streptococcus type 83 is shared by a number of streptococcal strains classified in Lancefield's group M. The cell wall polysaccharide of streptococcus type 83 cross-reacts with antibody to the C(s), or cell wall-like capsular, polysaccharide of Diplococcus pneumoniae, and this cross-reactivity may be a reflection that the streptococcal antigen possesses certain structural features which are similar to those of pneumococcal C and C(s) polysaccharides.

Filamentous capsulated streptococci from the human respiratory tract. 3. Immunochemical studies of the cross-reactivity between the cell wall antigens of a filamentous streptococcus and of pneumococcus.

A cell wall-associated polysaccharide has been isolated from a noncapsulated mutant, 89R50, of the alpha-hemolytic filamentous streptococcus of provisional capsular type 89. Chemical analysis of the polysaccharide indicates that it consists of galactosamine, glucosamine, glucose, and phosphorus. Immunological cross-reactivity was observed between the streptococcal cell wall antigen and antibody to the cell wall-like capsular polysaccharide of pneumococcus. This cross-reactivity appears attributable to similarities in the teichoic acid moieties rather than in the mucopeptide moieties of the two polymers. No chemical or immunological differences were observed in the cell wall carbohydrate of the noncapsulated streptococcus, 89R50, and that of its capsulated progenitor. It is suggested that antibody to this cell wall polysaccharide might serve as a basis for grouping other filamentous strains of streptococci of diverse capsular types, the cell wall antigens of which show similar cross-reactivity with that of pneumococcus.