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PubMed1996

[A preliminary study on the relationship between Streptococcus and Neisseria,Veillonella in an artificial mouth model]

The viable cell count of monobacterial plaque of Streptococcus and mixed bacterial plaque of streptococcus and Neisseria Veillonella,also the demineralization caused by the plaques were observed.The assumption that Neisseria and Veillonella might reduce demineralization of enamel caused by streptococcus was confirmed.The relationship between streptococcus and Neisseria,Veillonella were preliminarily found out.

Journal Article↗
PubMed2003

[Identification of Streptococcus species and Haemophilus influenzae by direct sequencing of PCR products from 16S-23S rRNA itergenic sacer regions].

To facilitate species level identification of bacteria without the requirement of presumptive identification, the paper describes a rapid identification method of bacteria by amplification and direct sequencing 16S-23S rDNA intergenic spacer regions (ISR) of the pathogens which cause the upper respiratory tract infective disease by Streptococcus and Haemophilus. Three pairs of primer targeting conserved sequences flanking the 3' end of 16S and the 5' end of 23S rRNA were used to amplify 16S~23S rRNA ISR of 7 streptococcus strains and 8 Haemophilus strains. The PCR products were separated by 1% agarose gel electrophoresis and the polymorphisms fragments were purified with the Wizard PCR Min-Prep Kit (Promega) and Protocol-SK131(Sangon). The nucleotide sequences of ISR inserts were determined by using the XEQTM DTCS Kitjj Terminator Cycle Sequencing and a CEQTM 2000XL DNA Analysis system (Backman Coulter) automatic DAN sequencer. Then those sequences were compared with known sequences on the GenBank. The alignment of nucleotide sequence, evolutionary distances and phylogenetic trees were analyzed by software DANMAN version 4.0. The PCR products were showed polymorphism patterns with agarose gel. One band was contained in streptococcus genus. The significant variation was found among the spacer sequences of different species in Streptococcus with the lengths of the spacer varying from 269 to 446 bp. All the ISR of the streptococcal species had a tRNA Ala gene in the spacer and the sequence identities varied from 78 to 88% within genera. It was found that some spacer sequence blocks were highly conserved between operons of a genome, whereas the presence of others was variable, three regions showed significant spatial variation. Most of the differences between the sequences came from several bases insertions/deletions and substitutions. There are two major bands in the Haemophilus biotypes (515 and 884 bp), the small ISR amplicon contained one tDNA coding for tRNA(Glu). In contrast to the large one contained two tRNA genes coding for tRAN(Ala) and tRNA(Ile). Two regions of repeating motifs with only A or T were present in higher copy numbers between tRAN(Ala) and tRNA(Ile). The phylogenetic trees varied from 97.5 to 98.8%. The PCR and direct sequencing of 16S-23S rRAN ISR were successful in the pathogen species identification.

English Abstract↗
PubMed1987

Experimental infection of lactating bovine mammary glands with Streptococcus uberis in quarters colonized by Corynebacterium bovis.

Twenty-seven quarters of 18 lactating dairy cows were inoculated intramammarily with 3.6 X 10(4) colony-forming units (CFU) of a strain of Streptococcus uberis isolated from a cow with clinical mastitis. Before quarters were inoculated, 22 were considered as naturally colonized with Corynebacterium bovis, and 5 were considered bacteriologically negative. Streptococcus uberis was isolated from all quarters within 2 days after inoculation, and all quarters developed clinical mastitis by 3 days after inoculation. Mastitis was acute, and most cows had increased rectal temperatures. The number of somatic cells increased significantly (P less than 0.05), and milk production decreased significantly. In many cows, rectal temperatures remained increased, and Str uberis was isolated from infected glands after intramammary and systemic antimicrobial treatments were given. A decreased number (110 CFU) of the same strain of Str uberis caused equally severe mastitis in 3 quarters colonized with C bovis and in 1 bacteriologically negative quarter in 2 cows. Streptococcus uberis was isolated from all inoculated quarters, and all quarters developed clinical mastitis by 2 days after inoculation. Two quarters colonized with C bovis and 2 bacteriologically negative quarters were inoculated once with 25 CFU and once with 240 CFU of a different strain of Str uberis (ATCC 27958). Streptococcus uberis was never isolated from inoculated quarters, and changes in milk yield or number of somatic cells were not observed.

Animals↗
PubMed1972

Humoral antibody responses of swine infected experimentally with group E streptococcus. I. Whole cell agglutinin response.

Reference streptococcal antisera and sera collected from swine infected experimentally (by intranasal inoculation or contact exposure) with group E Streptococcus (GES) were studied in a tube agglutination system using whole GES cells. Specificity studies revealed common group specific antigen among GES serotypes I and III, GES strains devoid of type specific antigen (untypable by ring precipitin testing) and group P and group U Streptococcus. The group specific antigens were not agglutinated by GES type specific antisera or by group specific antisera against Streptococcus groups A, B, C, D, F, G, H, K, L, M, N, or O. Results of the study suggested that GES serotypes I and III are invalid; i.e., they are devoid of type specific antigen. Groug E Streptococcus type specific antigens II, IV, and V were agglutinated significantly only by their homologous antisera. Experimentally infected swine developed significant titers against both the group and type specific antigen of GES. Antibodies appeared from three to eight weeks postexposure and persisted for the duration of the experiment (six months). The potential utilization of the whole cell agglutination (WCA) test for detection of GES carrier swine is discussed.

Agglutination Tests↗
PubMed1995

[Streptococcus pneumoniae-induced pulmonary consolidation prevented with tumor necrosis factor alpha monoclonal antibody in mouse].

Streptococcus pneumoniae stimulate mouse peritoneal macrophages to release tumor necrosis factor alpha (TNF alpha) in vitro. When penicillin was added to lysate bacterium, TNF alpha release was accelerated. 150 Kunming mice were infected with streptococcus pnumoniae through inspiration. Dynamic changes of TNF alpha concentration in serum and bronchoalveolar lavage fluid were detected; pulmonary pathological changes were also observed. It was found that TNF alpha monoclonal antibody significantly attenuates TNF alpha activity in serum and bronchoalveolar lavage fluid, white blood cell chemotaxis, emigation, and infiltration were inhibited. We conclude that streptococcus pneumoniae infection stimulates TNF alpha release, and TNF alpha is probably the major mediator that causes tissue damage during streptococcus pneumoniae infection. As penicillin accelerates TNFa release, single therapy of penicillin may worse tissue damage.

Animals↗
PubMed1997

[Primary peritonitis caused by Streptococcus pneumoniae].

Primary peritonitis caused by Streptococcus pneumoniae is a rare but serious complication of childbirth. We present here three cases of young women who developed abdominal pain after childbirth. All of the patients had fever with abdominal pain, diarrhea and clinical signs of peritonitis. In two cases a laparotomy was performed to remove pus. Cultures taken were positive for Streptococcus pneumoniae. Culture of vaginal swabs and blood cultures were also positive for the same pathogen. For the third patient, both vaginal swabs and blood cultures were positive for Streptococcus pneumoniae, antibiotic therapy only was administered. Outcome was favorable for all. We discuss the pathogenesis, clinical presentation, management and the usefulness for systematic search "for" Streptococcus pneumoniae in vaginal swabs.

Abdominal Pain↗
PubMed1984

A case study of Streptococcus group G infection in a dairy herd.

In this paper an outbreak of bovine mastitis in a dairy herd caused by Streptococcus group G is described. Initial identification of the organism as Streptococcus agalactiae was based upon hemolysis, esculin reaction, and CAMP reaction observed on blood agar used for bulk milk analysis. Initial therapy with a penicillin-containing, lactating cow product cured 24.4% of all streptococcal infections. Definitive serogrouping by coagglutination determined that the majority of infections were due to a weakly-hemolytic, esculin-negative Streptococcus group G. Treatment with a cephalosporin, lactating cow product was only moderately successful (54.9%). Dry-cow therapy with 300 mg cephalosporin eliminated 69.5% of refractory infections. Animals remaining infected following dry-cow therapy were culled. Histopathological study of parenchymal tissue in the lower portion of infected quarters revealed mild damage and slight involutionary changes, whereas, deep parenchymal areas appeared relatively unaffected.

Animals↗
PubMed1999

A DNA probe specific to Streptococcus sobrinus.

Three DNA fragments (SSB-1, -2 and -3) in the dextranase gene (dex) of Streptococcus sobrinus were amplified by polymerase chain reaction and used as DNA probes. The probes were examined for the specificity and the sensitivity of hybridization with DNA of oral streptococcal species. While probes SSB-1 and SSB-2 were specific to both S. sobrinus and Streptococcus downei, SSB-3 was specific only to S. sobrinus. SSB-3 was able to detect 5 ng of chromosomal DNA purified from S. sobrinus NIDR6715 and DNA extracted from 1 x 10(5) cells of the strain. In addition, SSB-3 could differentiate clinical isolates of S. sobrinus from Streptococcus mutans. These results suggest that SSB-3 is an effective DNA-probe to detect and to identify S. sobrinus.

Bacterial Proteins↗
PubMed1995

Homeologous recombination and mismatch repair during transformation in Streptococcus pneumoniae: saturation of the Hex mismatch repair system.

The ability of the Hex generalized mismatch repair system to prevent recombination between partially divergent (also called homeologous) sequences during transformation in Streptococcus pneumoniae was investigated. By using as donor in transformation cloned fragments 1.7-17.5% divergent in DNA sequence from the recipient, it was observed that the Hex system prevents chromosomal integration of the least and the most divergent fragments but frequently fails to do so for other fragments. In the latter case, the Hex system becomes saturated (inhibited) due to an excess of mismatches: it is unable to repair a single mismatch located elsewhere on the chromosome. Further investigation with chromosomal donor DNA, carrying only one genetically marked divergent region, revealed that a single divergent fragment can lead to saturation of the Hex system. Increase in cellular concentration of either HexA, the MutS homologue that binds mismatches, or HexB, the MutL homologue for which the essential role in repair as yet remains obscure, was shown to restore repair ability in previously saturating conditions. Investigation of heterospecific transformation by chromosomal DNA from two related streptococcal species, Streptococcus oralis and Streptococcus mitis, also revealed complete saturation of the Hex system. Therefore the Hex system is not a barrier to interspecies recombination in S. pneumoniae. These results are discussed in light of those described for the Mut system of Escherichia coli.

Adenosine Triphosphatases↗
PubMed2005

Acute otitis media caused by Streptococcus pyogenes in children.

BACKGROUND: Streptococcus pyogenes, or group A beta -hemolytic Streptococcus (GAS), is an important causative agent of bacterial pharyngotonsillititis and skin, soft-tissue, and invasive infections. Although it is also an important pathogen in acute otitis media (AOM), its exact role has not been determined. METHODS: Patients aged 0-18 years with AOM, from whom a specimen of middle-ear fluid was obtained and cultured during 1999-2003, were enrolled. Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and GAS were considered pathogens. Information collected included demographic characteristics, clinical history, and signs and symptoms. RESULTS: GAS otitis was observed in 350 (3.1%) of 11,311 episodes (of which 117 were also culture-positive for other pathogens). The other 10,961 episodes involved H. influenzae only (n = 2507), S. pneumoniae only (n = 2131), dual infection with H. influenzae and S. pneumoniae (n = 1290), M. catarrhalis only (n = 129), and other combinations of pathogens (n = 271). Increased age and Jewish ethnicity were independent, significant, positive risk factors for GAS AOM, and fall season was a negative risk factor. Episodes of GAS infection were less frequently bilateral, febrile, and accompanied by other systemic findings than were other episodes of other types of infection. Most patients with GAS AOM presented with acute drainage from the ears. A lower proportion of cases of AOM were due to GAS in children with recurrent AOM and in patients recently treated with antibiotics, compared with patients with AOM who did not have these factors. The risk for mastoiditis was highest among patients with GAS AOM, compared with patients infected with other pathogens: 11.6 episodes per 1000 episodes of GAS AOM, compared with 2.2, 0.3, and 0 episodes of mastoiditis per 1000 episodes of AOM due to S. pneumoniae, H. influenzae, and M. catarrhalis, respectively. CONCLUSION: Compared with AOM caused by pathogens other than GAS, GAS AOM is characterized by older age and higher local aggressiveness manifested by lower rates of fever and respiratory symptoms and higher rates of tympanic perforation and mastoiditis.

Acute Disease↗
PubMed2004

Increasing antibiotic resistance of streptococcus species in New York City.

OBJECTIVE: Streptococcus species are common pathogens in head and neck infections and are leading causes of morbidity and mortality. Emerging penicillin-resistant streptococcal pathogens have shifted empirical antibiotic therapy in favor of valuable alternatives, including erythromycin and clindamycin. This study was undertaken to determine the magnitude of antimicrobial resistance to these antibiotics. STUDY DESIGN: Retrospective review. METHODS: A retrospective study of two streptococcal species isolates, Streptococcus pyogenes (163 specimens) and Streptococcus pneumoniae (164 specimens), collected between January 1, 2001 and January 1, 2002 at two academic institutions. The antibiotic susceptibility patterns were analyzed for penicillin, erythromycin, and clindamycin according to the National Committee for Clinical Laboratory Standards. RESULTS: Fourteen percent to 34% of S. pyogenes isolates were erythromycin-resistant, and 0% to 28% were clindamycin-resistant. None of the S. pyogenes isolates were resistant to penicillin. Of the S. pneumoniae isolates, 33% to 50% were resistant to erythromycin, and 18% to 33% were resistant to clindamycin. The penicillin resistance levels for S. pneumoniae were 0% to 45%. CONCLUSIONS: Our antimicrobial resistance levels for S. pyogenes and S. pneumoniae significantly exceeded national and worldwide levels of erythromycin and clindamycin resistance. With a diverse population of over 8 million residents and high physician supply, our model is a microcosm for the study of antimicrobial use and susceptibility patterns and of clinical failure.

Clindamycin↗
PubMed1996

Surface location of HPr, a phosphocarrier of the phosphoenolpyruvate: sugar phosphotransferase system in Streptococcus suis.

HPr is a low-molecular-mass phosphocarrier protein of the bacterial phosphoenolpyruvate (PEP): sugar phosphotransferase system (PTS) found in the cytoplasm or associated with the inner surface of the cytoplasmic membrane. Treatment of Streptococcus suis cells with a Sorvall Omnimixer, a technique used to extract cell surface components, resulted in the extraction of a major protein with a molecular mass of 9 kDa. Several lines of evidence suggested that this protein was HPr: (i) the S. suis protein showed homology over the first 35 N-terminal amino acid residues with the HPrs of Streptococcus salivarius and Streptococcus mutans, including the signature sequence for the site of PEP-dependent phosphorylation; (ii) it cross-reacted with the S. salivarius anti-HPr antibody preparation; (iii) it could be phosphorylated by enzyme I at the expense of PEP, and by a membrane-associated kinase at the expense of ATP; and (iv) it possessed phosphocarrier activity when used as a source of HPr in an in vitro PTS assay. The data suggested that a portion of the cellular HPr is associated with the external cell surface in S. suis, a result that was confirmed by immunogold electron microscopy. The cellular HPr of S. suis consisted of two forms that could be distinguished by the presence or the absence of the N-terminal methionine. Amino acid sequence analysis indicated that the cell-surface-associated HPr of S. suis lacked the N-terminal methionine residue.

Amino Acid Sequence↗
PubMed2006

Overestimation of Streptococcus mutans prevalence by nested PCR detection of the 16S rRNA gene.

This study was carried out in order to compare two PCR-based methods in the detection of Streptococcus mutans. The first PCR method was based on primers for the 16S rRNA gene and the second method was based on specific primers that targeted the glucosyltransferase gene (gtfB). Each PCR was performed with eight different streptococci from the viridans group, five other streptococci and 17 different non-streptococcal bacterial strains. Direct use of the S. mutans 16S rRNA gene-specific primers revealed that Streptococcus gordonii and Streptococcus infantis were also detected. After amplifying the 16S rRNA gene with universal primers and subsequently performing nested PCR, the S. mutans-specific nested primers based on the 16S rRNA gene detected all tested streptococci. There was no cross-reaction of the gtfB primers after direct PCR. Our results indicate that direct PCR and nested PCR based on 16S rRNA genes can reveal false-positive results for oral streptococci and lead to an overestimation of the prevalence of S. mutans with regards to its role as the most prevalent causative agent of dental caries.

DNA Primers↗
PubMed1990

Glucosyltransferase production by Streptococcus sanguis Challis and comparison with other oral streptococci.

Glucosyltransferase (GTF) activity in batch cultures of Streptococcus sanguis strain Challis in defined medium was maximum at peak growth and declined rapidly on further incubation into stationary phase. Activity was present in spent culture medium and was associated with 2 polypeptides of approximate Mrs 170 kDa (90% of activity) and 155 kDa (about 10% of activity). Other S. sanguis strains produced similar antigenically-related polypeptides but with varying activities, and antibodies to the S. sanguis enzyme did not react with enzymes produced by other species of oral streptococci. Increasing the [Na+] reduced GTF production by S. sanguis strains Challis and NCTC 7865, and by Streptococcus sobrinus, but not by Streptococcus salivarius. Addition of Tween 80 to cultures caused a rapid inhibition of GTF synthesis by strain Challis, but not by strain NCTC 7865. Benzyl alcohol had a slower and less inhibitory effect on GTF production by strain Challis. Tween 80 generally inhibited to varying degrees GTF production by other oral streptococci through in S. sobrinus it was stimulated. The results suggest controls operating on GTF synthesis and secretion by different strains of oral streptococci appear to be diverse.

Animals↗
PubMed1985

Streptococcus-Escherichia coli shuttle vector pSA3 and its use in the cloning of streptococcal genes.

A shuttle vector that can replicate in both Streptococcus spp. and Escherichia coli has been constructed by joining the E. coli plasmid pACYC184 (chloramphenicol and tetracycline resistance) to the streptococcal plasmid pGB305 (erythromycin resistance). The resulting chimeric plasmid is designated pSA3 (chloramphenicol, erythromycin, and tetracycline resistance) and has seven unique restriction sites: EcoRI, EcoRV, BamHI, SalI, XbaI, NruI, and SphI. Molecular cloning into the EcoRI or EcoRV site results in inactivation of chloramphenicol resistance, and cloning into the BamHI, SalI, or SphI site results in inactivation of tetracycline resistance in E. coli. pSA3 was transformed and was stable in Streptococcus sanguis and Streptococcus mutans in the presence of erythromycin. We have used pSA3 to construct a library of the S. mutans GS5 genome in E. coli, and expression of surface antigens in this heterologous host has been confirmed with S. mutans antiserum. A previously cloned determinant that specifies streptokinase was subcloned into pSA3, and this recombinant plasmid was stable in the presence of a selective pressure and expressed streptokinase activity in E. coli, S. sanguis (Challis), and S. mutans.

Chloramphenicol↗
PubMed1981

Effect of human saliva on glucose uptake by Streptococcus mutans and other oral microorganisms.

We examined the effects of human whole salivary supernatant and parotid fluid on glucose uptake by Streptococcus mutans, Streptococcus sanguis, Streptococcus mitis, Actinomyces viscosus, Staphylococcus aureus, and Escherichia coli. The following three effects of saliva were observed: (i) inhibition of glucose uptake (S. mutans, S. sanguis), (ii) promotion of a transient, rapid (0 to 30 s) burst of glucose uptake (S. mutans, S. sanguis), and (iii) enhancement of glucose uptake (S. mitis, A. viscosus, S. aureus, E. coli). We observed no differences between the effects of whole salivary supernatant and the effects of parotid fluid. Heat treatment (80 degrees C, 10 min) of saliva or the addition of dithiothreitol abolished inhibition of glucose uptake. Supplementation of saliva with H(2)O(2) potentiated inhibition of glucose uptake. S. mitis and A. viscosus, which were stimulated by saliva alone, were inhibited by H(2)O(2)-supplemented saliva; 50% inhibition of glucose uptake by S. mutans and S. mitis required ca. 10 muM H(2)O(2) in 50% (vol/vol) saliva. Loss of the inhibitory action of saliva occurred at about 5% (vol/vol) saliva. Supplementation of saliva dilutions with SCN(-) and H(2)O(2) extended the inhibitory activity to solutions containing ca. 0.2% (vol/vol) saliva. We suggest that the salivary lactoperoxidase-SCN(-)-H(2)O(2) system is responsible for the inhibitory activity of saliva reported here. Furthermore, we concluded that lactoperoxidase and SCN(-) are present in saliva specimens in concentrations that exceed minimal inhibitory levels by factors of ca. 500 and 10 to 20, respectively. The resistance of A. viscosus, S. aureus, and E. coli to the inhibitory potential of saliva alone was probably due to the production of catalase by these organisms. The resistance of S. mitis may have been due to special effects of saliva on H(2)O(2) accumulation by this organism compared with S. mutans and S. sanguis. The basis of saliva-dependent enhancement of glucose uptake and the basis of promotion of a transient, rapid burst of glucose uptake are unknown. The role of the salivary lactoperoxidase-SCN(-)-H(2)O(2) system in the oral microbial ecosystem is discussed.

Actinomyces↗
PubMed1985

Competitive displacement of mutans streptococci and inhibition of tooth decay by Streptococcus salivarius TOVE-R.

The ability of Streptococcus salivarius TOVE-R to displace virulent representatives of the most prevalent human mutans streptococci from the teeth of rats, and thereby to inhibit caries, was studied. Streptococcus mutans 10449S- or Streptococcus sobrinus 6715-13WT-infected specific-pathogen-free rats consuming a high-sucrose diet were inoculated by TOVE-R. The infectants were differentially recovered from swabs of the teeth over the time course of infection and from sonically treated material of extracted teeth and excised tongues. Despite initial colonization of the teeth by the mutans streptococci, TOVE-R colonized the teeth, unlike other essentially nonvirulent plaque formers already described. It did not colonize the tongues of the rats. TOVE-R emerged and persisted as a prominent member of the plaque ecology. There was an associated decline in the mutans streptococci on the teeth, and this decline was associated with significant inhibition of the caries component attributable to 10449S infection (56%) and to 6715-13WT infection (52%). TOVE-R did not reliably inhibit the component of fissure caries attributable to the nonmutans indigenous flora of the rats. TOVE-R itself induced no detectable decay. The data suggest the potential therapeutic utility of TOVE-R to inhibit caries by displacement of mutans streptococci from the teeth. These results supplement the already reported ability of TOVE-R to preempt initial colonization of teeth by the mutans streptococci.

Animals↗
PubMed1989

Molecular and immunochemical characterization of recombinant Escherichia coli containing the spaA gene region of Streptococcus sobrinus.

We identified and characterized a recombinant Escherichia coli containing the entire gene for surface protein antigen A (spaA) of Streptococcus sobrinus 6715. The recombinant E. coli was isolated from a cosmid gene bank of size-fractionated S. sobrinus DNA fragments, and recombinants expressing the SpaA protein were detected immunologically. Subcloning experiments showed that the DNA sequences encoding the SpaA protein could be isolated on two contiguous EcoRI fragments, 3.7 and 3.3 kilobases (kb) in size, both contained on a 16.2-kb BglII fragment. Southern blot hybridization experiments using the EcoRI fragments to probe genomic DNAs from various serotypes of the mutans group of streptococci revealed DNA sequence homology not only to S. sobrinus 6715 (serotype g) chromosomal DNA but also to S. sobrinus serotype d DNA. Weak hybridization signals to Streptococcus mutans serotypes c, e, and f and to Streptococcus cricetus serotype a were observed with the 3.3-kb EcoRI fragment. These results suggest that the coding sequence for the spaA gene is probably conserved in S. sobrinus strains. Plasmid-encoded polypeptides made in E. coli minicells revealed that transcription of the spaA gene was initiated on the 3.7-kb EcoRI fragment and that its product size was about 210 kilodaltons. The cloned SpaA protein was purified from the periplasmic protein of E. coli, and monospecific antiserum against the cloned product was prepared in rabbits. The data obtained from various physiochemical and immunological procedures allowed us to conclude that the coding sequence for the entire spaA gene of S. sobrinus 6715 had been successfully cloned in E. coli and that faithful expression of the cloned product could be obtained.

Bacterial Proteins↗