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PubMed1990

Involvement of human mucous saliva and salivary mucins in the aggregation of the oral bacteria Streptococcus sanguis, Streptococcus oralis, and Streptococcus rattus.

The contribution of human parotid (Par) and submandibular/sublingual (SM/SL) saliva and of the human whole salivary mucin fraction (HWSM) to saliva-induced bacterial aggregation was studied for S. sanguis C476, S. oralis I581, and S. rattus HG 59. The mucous SM/SL saliva showed a much higher aggregation potency towards the S. sanguis and S. oralis strain than did the serous Par saliva. The SM/SL saliva-induced aggregation was observed after 30 min, at 60 min followed by the Par saliva-induced aggregation, and showed a 4-fold higher aggregation titer of 128 for S. sanguis, and an 8-fold higher titer of 516 for S. oralis. In contrast, the Par saliva showed a slightly higher aggregation activity than the SM/SL saliva towards S. rattus as judged by a twofold higher titer of 64. Morphologically, however, the SM/SL saliva-induced aggregation of S. rattus was far more pronounced as was also found for S. sanguis. Finally, the HWSM-induced aggregation showed a 4 to 8-fold higher titer than the originating salivary source, measuring 2048 for S. oralis and 128 for S. rattus. Moreover, no difference was observed in aggregation activity between the HWSM from whole saliva of a blood group O donor and the HWSM from SM/SL saliva of a blood group A donor. All the data point to an important, though not exclusive role of the human salivary mucin fraction in the saliva-induced aggregation of these strains.

Blood Group Antigens↗
PubMed1975

Streptococcus salivarius, Streptococcus sanguis and Streptococcus "mitis" as indicators of contamination of root canal cultures.

Small samples were taken from the first drop of saliva entering an operation field for root canal treatment isolated by rubber dam, which was intentionally leaky. The samples were primarly cultured in TAS- and BLH-medium and on MS-agar aerobically. The culture media were inoculated directly and via transport medium (VMG III). The cultures were analysed for Strep. salivarius, Strep. sanguis and/or Strep. "mitis" after subculture on MS-agar as soon as visible growth had appeared in the broth media and again after a further 2 days. The following observations were made: 1. Strep. salivarius was almost regularly found in either or both of TAS- and BLH-medium at primary culture of the samples contaminated with saliva. The result was the same whether these broth media were inoculated directly or via VMG III. 2. Strep. salivarius was always found in mixed cultures and was nearly always accompanied by Strep. sanguis and/or Strep. "mitis". 3. Strep. salivarius as well as Strep. sanguis survived two days after visible growth significantly more oftern in BLH-medium than in TAS-medium. The findings lend support to the hypothesis based on clinical studies that when present in root canal cultures Strep. salivarius is ascribable to contamination with saliva.

Adolescent↗
PubMed1991

[Manifestations of Streptococcus infection resulting from various serologic groups of streptococcus].

44 autopsy cases (from 1985 to 1990) are studied out of which in 38 cases the diseases were produced by streptococcus of group A. In 18 cases there was a pharyngeal or extra-pharyngeal generalized streptococcus infection (scarlet fever). Moderately pronounced local damage, mainly pneumonia, were found in 20 cases. In 3 other cases the disease was produced by group B streptococcus, in 2 cases by streptococcus D and in 1 case by streptococcus of G group. Group A streptococcus was encountered mainly in children older than 6 months (31 cases), B and D at an earlier age (particularly B streptococcus). Morphologically, there were no essential differences connected with different streptococcus groups. The infection in most cases was correlated with a respiratory diseases, more frequently with influenza or respiratory-syncytial infection this favouring more grave course of streptococcus infection.

Child↗
PubMed2003

Reappraisal of the taxonomy of the Streptococcus bovis/Streptococcus equinus complex and related species: description of Streptococcus gallolyticus subsp. gallolyticus subsp. nov., S. gallolyticus subsp. macedonicus subsp. nov. and S. gallolyticus subsp. pasteurianus subsp. nov.

'Streptococcus bovis/Streptococcus equinus' is a large bacterial complex including different species frequently isolated from infections of humans (Streptococcus gallolyticus, Streptococcus infantarius) or animals (S. bovis, S. equinus, Streptococcus alactolyticus). The separation of S. bovis into three different biotypes has been partially correlated with genetic differentiation. In addition, recent advances in bacterial phylogeny have led to the inclusion of Streptococcus macedonicus and Streptococcus waius in this complex. The aim of this study was to improve physiological differentiation between species related to the complex and to clarify their respective phylogenetic positions. In this study, physiological, genetic and phylogenetic analyses of a set of 88 streptococcal strains were performed. The diversity of strains of S. bovis biotype II was analysed, and it was confirmed that they belong to different species, either S. equinus or S. infantarius. It was demonstrated that S. gallolyticus, S. bovis biotype II.2, S. macedonicus and S. waius form a single DNA cluster separated into three different subspecies. They are delineated by different biochemical traits, limited DNA-DNA relatedness and noticeable divergence in 16S rDNA sequences. According to the current definition of species, the names S. gallolyticus subsp. gallolyticus subsp. nov., S. gallolyticus subsp. pasteurianus subsp. nov. and S. gallolyticus subsp. macedonicus subsp. nov. are proposed for these three subspecies.

Animals↗
PubMed2000

An unusual Streptococcus from human urine, Streptococcus urinalis sp. nov.

Biochemical, molecular chemical and molecular genetic studies were performed on an unknown Gram-positive, catalase-negative, chain-forming coccus isolated from the urine of a patient suffering from cystitis. Comparative 16S rRNA gene sequencing showed that the organism is a member of the 'pyogenic subgroup' of the genus Streptococcus and has a close affinity with Streptococcus pyogenes and Streptococcus canis. The unknown coccus was, however, readily distinguished from these species and other streptococci by biochemical tests and electrophoretic analysis of whole-cell proteins. Based on phenotypic and phylogenetic evidence, it is proposed that the unknown bacterium be classified as a new species of the genus Streptococcus, Streptococcus urinalis sp. nov. The type strain of Streptococcus urinalis is CCUG 41590T.

Cystitis↗
PubMed1994

[Comparative antibacterial activity of cefpodoxime against Haemophilus influenzae, Streptococcus pyogenes, Streptococcus pneumoniae and Moraxella catarrhalis].

The antimicrobial activity of cefpodoxime (Podomexef, CAS 80210-62-4) against 236 clinical isolates of H. influenzae, Moraxella catarrhalis, Streptococcus pyogenes and Streptococcus pneumoniae was investigated and compared with that of another 8 commonly used oral antibiotics. beta-Lactamase negative, beta-lactamase positive and multiresistant strains of H. influenzae were inhibited by cefpodoxime at a concentration of 0.13 mg/l. 10% of Moraxella catarrhalis isolates were moderately susceptible to cefpodoxime, with minimum inhibitory concentration (MIC) of cefpodoxime ranging between 0.13 and 2.0 mg/l. All isolates of Streptococcus pyogenes and Streptococcus pneumoniae were susceptible to < or = 0.25 mg/l cefpodoxime. Cefpodoxime was clearly more active than the older oral cephalosporins against all species tested. The activity was comparable to that of cefixime against all species except Streptococcus pneumoniae, against which cefpodoxime was more active than cefixime.

Bacteria↗
PubMed2001

Wound erysipelas following appendectomy caused by group B beta-hemolytic Streptococcus (Streptococcus agalactiae).

BACKGROUND: Case description of a patient who developed erysipelas of the surgical wound following appendectomy for acute appendicitis, and literature review of invasive group B streptococcal infections. METHODS: A 65-year-old man with perforated appendicitis underwent urgent appendectomy and drainage. Antibiotic prophylaxis with tobramycin (100 mg) and metronidazole (500 mg) was administered. At surgery, a phlegmon was identified with free perforation of the appendix and purulent peritoneal fluid. Appendectomy, irrigation with 0.9% NaCl solution, and drainage with a Silastic closed-suction drain was performed. A literature search in all languages was performed using MEDLINE, using the search terms surgical site infection, wound infection, group B streptococcus, Streptococcus agalactiae, necrotizing fasciitis, and postoperative infection. RESULTS: Erysipelas of the surgical wound developed on the fourth postoperative day. Intravenous penicillin and amoxicillin/clavulanic acid were administered empirically. Culture of the wound drainage identified Streptococcus agalactiae and a few colonies of Escherichia coli. The broad-spectrum antibiotic was discontinued, and a 10-day course of penicillin was completed. CONCLUSIONS: Erysipelas of the surgical wound is unusual, and infection with group B streptococci is rare compared with infection by group A streptococci. Streptococcus agalactiae is recognized to be increasingly virulent, with an increasing predilection for bacteremic infections in healthy hosts. Although Streptococcus agalactiae remains highly susceptible to antimicrobial agents effective against gram-positive cocci, the changing epidemiology and potentially invasive nature of these infections should have clinicians alert to the possibility of infection caused by group B streptococci.

Aged↗
PubMed1991

[Structure of the beta-galactosidase gene from Streptococcus diacetylactis 144 and its expression in Escherichia coli and Streptococcus diacetylactis cells].

The ability of industrial strains of mesophylic Streptococcus diacetylactis to synthesize the enzyme beta-galactosidase has been studied. Among the 22 studied strains 8 were found to synthesize the enzyme. Plasmid DNA was isolated from the Streptococcus diacetylactis strain 144 possessing the highest level of beta-galactosidase activity. The cells of the strain harbour the 35, 40 and 60 kb plasmids. The alpha-galactosidase genes from this strain was cloned in Escherichia coli cells. The gene is located on the BglIII DNA fragment of the total plasmid DNA from Streptococcus diacetylactis the size of 2.8 kb. Following the Sau3A restriction endonuclease digestion the gene was subcloned on a birepliconed vector plasmid pCB20. The latter is capable of replication in the Gram-negative as well as Gram-positive microorganisms. The pCB20 derivatives carrying the different length fragments with the beta-galactosidase gene were isolated. DNA of an obtained plasmid was used for transformation of Streptococcus diacetylactis cells. The presence of the recombinant plasmid in streptococcus strain 144 results in the 1.8 fold increase in beta-galactosidase production.

Escherichia coli↗
PubMed2004

Molecular analysis of age-related changes of Streptococcus anginosus group and Streptococcus mitis in saliva.

The purpose of this study was to survey the prevalence of streptococcal species, especially Streptococcus anginosus (which has been reported to be associated with cancer in the upper digestive tract), Streptococcus constellatus, and Streptococcus intermedius in the saliva of different age groups. A sequence analysis of 16S rDNA was performed and DNA quantified using real-time polymerase chain reaction. The S. anginosus level increased with age, whereas the levels of S. constellatus and S. intermedius did not change. Streptococcus mitis was the predominant species in the saliva of all the age groups but, unlike the S. anginosus, the proportion of S. mitis in the salivary bacteria decreased with age. The increase in S. anginosus with age should be carefully monitored because of its association with diseases, including cancer.

Adult↗
PubMed1984

In-vivo dental plaque-forming ability and relative cariogenicity of the bacteria Streptococcus mitis and Streptococcus sanguis I and II in mono-infected gnotobiotic rats.

Sixteen strains of Streptococcus mitis, Streptococcus sanguis I and Strep. sanguis II were tested for cariogenic potential and in-vivo plaque-forming ability in a gnotobiotic WAG/RIJ rat test system. All strains produced far less fissure plaque in vivo than strains of Streptococcus milleri or Streptococcus mutans. There was less extracellular matrix around cells of Strep. mitis or Strep. sanguis than around Strep. mutans, in the fissures. Dense sheets of cells were observed only with Strep. mutans. Some localized colonization of exposed smooth surfaces occurred with most strains. Strep. mitis produced no caries in three tests, low-caries scores in two tests and high-caries scores in one test. A single strain of Strep. mitis produced a highly-cariogenic variant able to ferment raffinose. Strep. sanguis I induced low-levels of caries in 12 tests; one test of NCTC 7865 produced moderate levels of caries, and another test of 311 produced no caries. Strep. sanguis 311 was dextran-negative. Strep. sanguis II strains induced no caries in three tests, low caries scores in six tests and moderate levels of caries with Strep. sanguis 402. No strain of Strep. mitis or Strep. sanguis was able to induce smooth-surface lesions.

Animals↗
PubMed2006

A Comparison of group A Streptococcus versus Streptococcus pneumoniae pneumonia.

BACKGROUND: St reptococcus pyogenes is an uncommon cause of community-acquired pneumonia in children. Further, its clinical course in comparison to pneumonia caused by Streptococcus pneumonia has not been previously highlighted. METHODS: We reviewed medical records of children 0-18 years of age from April 1983 to April 2005, with discharge diagnoses of invasive disease caused by group A streptococcus (GAS) (Streptococcus pyogenes), or Streptococcus pneumonia (SP) or pneumonia. Data were extracted from the charts, and a comparison of clinical characteristics between the 2 etiologies was performed. Confirmed disease required blood or pleural fluid isolates. Patients with single isolates of GAS in tracheobronchial secretions or sputum were classified as having presumed disease caused by GAS. Patients with confirmed disease due to GAS and SP were compared with respect to clinical characteristics. RESULTS: Of 103 patients with invasive GAS disease, 12 (11.6%) had confirmed GAS lobar pneumonia. In addition 7 patients had presumed GAS pneumonia. There were 54 patients with confirmed SP pneumonia. Most children who had GAS pneumonia were healthy and recovered completely. Compared with patients with confirmed SP pneumonia, those with confirmed GAS pneumonia had more frequent and larger effusions, more culture positive effusions, had prolonged fever, and had longer hospitalizations. There was not an increasing trend to GAS pneumonia over the 22-year period. There was not a predominant serotype responsible for the pneumonias. CONCLUSIONS: Lobar GAS pneumonia represents approximately 11% of all cases of invasive disease in this institution during a 22-year period. Compared with patients with SP pneumonia, it appears to cause more effusions and morbidity. The organism is also more frequently recovered from pleural fluid.

Adolescent↗
PubMed1986

Coaggregation between Actinomyces viscosus with Streptococcus pyogenes and Streptococcus agalactiae.

Interbacterial coaggregation between Actinomyces viscosus indigenous to the human mouth and Streptococcus pyogenes and Streptococcus agalactiae was studied. Fifteen of twenty-six strains of Streptococcus pyogenes and thirteen of thirty-one Streptococcus agalactiae showed a coaggregation with Actinomyces viscosus strain. The results show that the coaggregation mechanism required calcium and was dependent on pH. Some coaggregations were inhibited by 0.06 M. lactose and by 1 M. NaCl.

Actinomyces↗
PubMed1991

Streptococcus crista sp. nov., a viridans streptococcus with tufted fibrils, isolated from the human oral cavity and throat.

We studied strains of an unusual streptococcus that superficially resembles Streptococcus sanguis but has fibrils that are arranged in lateral tufts. These strains were originally isolated from human throats and oral cavities and have been referred to previously as "Streptococcus sanguis I," the "CR group," and the "tufted-fibril group." Until now, insufficient phenotypic data have been available to allow reliable differentiation of these strains from other viridans streptococcal species, particularly the species in the S. sanguis group. Recently, workers have proposed a scheme of phenetic tests that is based on 4-methylumbelliferyl-linked substrates and conventional biochemical tests and allows the tufted-fibril group to be differentiated; these organisms differ from other viridans species in being able to hydrolyze arginine but not esculin and in producing alpha-L-fucosidase but not beta-glucosidase or alkaline phosphatase. These data, together with the results of our DNA-DNA hybridization experiments and the unusual ultrastructure of the tufted-fibril strains as determined by electron microscopy, demonstrate that these organisms represent a new species, for which the name Streptococcus crista is proposed. The DNA base composition is 42.6 to 43.2 mol% G + C. The type strain is strain CR311 (= NCTC 12479).

DNA, Bacterial↗
PubMed1999

Streptococcus intestinalis Robinson et al. 1988 and Streptococcus alactolyticus Farrow et al. 1984 are phenotypically indistinguishable.

The one-dimensional whole-cell protein patterns and a variety of biochemical characteristics of the type and reference strains of Streptococcus intestinalis and Streptococcus alactolyticus were studied. All the data revealed that strains of both species were indistinguishable. Reported differences in haemolytic activity and presence of Lancefield antigens were not reproduced. All strains were alpha-haemolytic. The S. intestinalis type strain possessed the group G antigen, but a second S. intestinalis reference strain and all of the S. alactolyticus strains possessed the group D antigen. All strains produced urease activity (albeit some after prolonged incubation), a characteristic considered important for S. intestinalis. Given the congruence between whole-cell protein electrophoresis and percentage of DNA-DNA hybridization, these data suggest that Streptococcus intestinalis Robinson et al. 1988 is a junior synonym of Streptococcus alactolyticus Farrow et al. 1984.

Animals↗