Research progress of prevention and treatment of oral and oropharyngeal diseases by Streptococcus salivarius K12 / 中国医师杂志

Streptococcus salivarius K12 is a kind of bacteria that settled in the mucosal epithelium of human mouth and nasopharynx shortly after human birth. It is found that Streptococcus salivarius K12 is a probiotic beneficial to human health. Many studies have confirmed that Streptococcus salivarius K12 has bioactive effects against oral and oropharyngeal inflammation and infection, dental caries, halitosis and oral epithelial damage. This paper reviews the research progress of Streptococcus salivarius K12 in the prevention and treatment of oral and oropharyngeal diseases.

Probiotics study with Streptococcus salivarius and its ability to produce bacteriocins and adherence to KB cells / Estudo de probióticos Streptococcus salivarius e sua habilidade de produzir bacteriocinas e aderência à células KB

Abstract Introduction Streptococcus salivarius is a dominant oral species and the best suitable candidate for probiotic of the oral cavity. Since Streptococcus salivarius is able to produce bacteriocins against Streptococcus pyogenes interest has been focused on the use of it as a probiotic to avoid sore throats by Streptococcus pyogenes. Objective This study is for selecting Streptococcus salivarius strains for potential use as probiotics for the oral mucosa, that is, production of bacteriocin against Streptococcus pyogenes and the ability to bind to KB cells. Material and method Tongue material from 45 students was collected and seeded on Mitis Salivarius Agar plaques. The strains were tested by the production of bacteriocin-like substances (BLIS) against S. pyogenes, biochemically and PCR for identification of S. salivarius. The best strains were tested for adherence to KB cells. Briefly, S. salivarius strains were cultured in broth, washed and suspended at 108cells/ml. KB cells were inoculated into plaques, washed and incubated with the bacteria, for adhesion. These were washed for lysis of the KB cells and release bacteria for determination of CFU. Result The bacteriocin test showed that 133 strains presented inhibition of S. pyogenes. The samples tested for adhesion to KB cells, presented different profiles and only three strains presenting high adhesion capacity. Conclusion The selection of strains of Streptococcus salivarius with high inhibitory activity against Streptococcus pyogenes, as well as adherence to KB cells leads us to the next future step, that is, to use the best strains for in vivo colonization tests

Resumo Introdução Streptococcus salivarius é uma espécie dominante na cavidade bucal e tem sido indicada como um ótimo candidato para uso como probiótico. Visto que a espécie Streptococcus salivarius é capaz de produzir bacteriocinas contra Streptococcus pyogenes, desenvolveu-se interesse no uso desse microrganismo como probiótico, para evitar amigdalites causadas por Streptococcus pyogenes. Objetivo A pesquisa em questão tem o objetivo de selecionar cepas de Streptococcus salivarius para seu uso potencial como probióticos na cavidade bucal, ou seja, produção de bacteriocinas contra Streptococcus pyogenes e habilidade de aderência à células KB. Material e método Coletou-se material de língua de 45 estudantes e semeou-se em placas de ágar Mitis Salivarius. As amostras foram testadas para verificar a produção de substâncias semelhantes à bacteriocina (BLIS) contra S. pyogenes, bioquimicamente e através de PCR para identificação de S. salivarius. As melhores cepas foram testadas quanto aderência à células KB. Resumidamente, as cepas de S. salivarius foram cultivadas em caldo, lavadas e suspensas à correspondência de 108 cels/ml. As células KB foram inoculadas em placas, lavadas e incubadas com as bactérias, para adesão. Estas foram lavadas para lise das células KB e liberação das bactérias para determinação de UFC. Resultado O teste de bacteriocina, mostrou que 133 cepas apresentaram atividade inibitória contra Streptococcus pyogenes. As cepas testadas para aderência à células KB, apresentaram diferentes perfis e somente três com alta capacidade de adesão. Conclusão: A seleção de cepas de Streptococcus salivarius com alta atividade inibitória contra Streptococcus pyogenes, bem como aderência a células KB, pode nos levar ao próximo passo, ou seja, o uso das melhores cepas para o estudo de colonização in vivo.

Construction of a low-pH-sensing system in Streptococcus mutans / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To construct a low-pH-sensing system in Streptococcus mutans (S. mutans) and to visually detect the pH in situ.</p><p><b>METHODS</b>Promoter of ureaseⅠ(PureⅠ) and green fluorescence protein (gfp) DNA fragments were amplified by polymerase chain reaction (PCR) from the genome of Streptococcus salivarius 57.I and S. mutans containing the gfp fragment. The two amplified DNA fragments were ligated together and further integrated into pDL278 to construct the recombinant plasmid pDL278-pureⅠ-gfp. This recombinant plasmid was then transformed into S. mutans UA159 cells. Subsequently, the intensity of the optical density per unit area of the low-pH-sensing system was measured and compared under different pH conditions and different processing times.</p><p><b>RESULTS</b>PureⅠ and gfp DNA fragments were amplified successfully with the correct molecule sizes (450 and 717 bp, respectively). The recombinant plasmid pDL278-pureⅠ-gfp was constructed and further verified by PCR and sequencing. The intensity of the optical density per unit area of the low-pH-sensing system increased with decreasing pH and increasing processing time.</p><p><b>CONCLUSIONS</b>A low-pH-sensing system was constructed successfully in S. mutans. Our research verified that pureⅠ of Streptococcus salivarius can function well in S. mutans as an acid induced promoter, and provided a new method of detecting the pH of plaque biofilms in situ.</p>

A Case of Streptococcus salivarius Meningitis in a Patient with Cerebrospinal Fluid Rhinorrhea after Skull Base Fracture / 대한임상미생물학회지

Streptococcus salivarius meningitis is very uncommon, and most cases are iatrogenic, occurring after invasive procedures such as spinal anesthesia or lumbar puncture etc.. Post-traumatic occurrence of this infection is especially rare. A 20-year-old man with a previous history of skull base fracture was seen at the emergency department with signs of acute bacterial meningitis. The CSF had a few gram positive cocci with neutrophilic pleocytosis, which were identified as S. salivarius by the Vitek system (bioMerioux, Inc., Hazelwood, MO, USA), rapid ID 32 Strep (bioMerieux, Marcy-l'Etoile, France) and 16S rRNA sequencing. The microorganism showed intermediate resistance to penicillin (MIC=0.25 microg/mL) but was susceptible to cefotaxime (MIC=0.25 microg/mL) and vancomycin (MIC= 0.75 microg/mL). The patient was treated with ceftriaxone and vancomycin. He also had his CSF leakage repaired by an endoscopic approach. To our knowledge, this is the first case of S. salivarius meningitis reported in Korea.

Streptococcus salivarius pneumonia with pulmonary nocardiosis in a rheumatoid arthritis patient treated with immunosuppressants / 대한내과학회지

Streptococcus salivarius is a Gram-positive organism that belongs to the viridians group of streptococci. It is a relatively non-virulent bacterium that is part of the normal flora. It is rarely isolated from blood and is usually considered a contaminant. Nevertheless, S. salivarius may cause life-threatening infections, especially in immunocompromised hosts. There have been relatively few reports of S. salivarius pneumonia. Nocardiosis is also a rare opportunistic infection. Pulmonary nocardiosis is difficult to diagnose and, consequently, the diagnosis is often delayed. We report an unusual presentation with multiple pulmonary mass-like consolidations caused by a mixed infection of S. salivarius and Nocardia sp. in a 58-year-old man with rheumatoid arthritis who was taking oral corticosteroid, methotrexate, and leflunomide. The patient's symptoms and radiographic findings improved after six weeks of antibiotic therapy

Producción de ácido láctico por una mezcla de Lactococcus lactis y Streptococcus salivarius en fermentaciones en discontinuo / Lactic acid production from a mixture of cultures of Lactococcus lactis and Streptococcus salivarius using batch fermentation

Se estudió la producción de ácido láctico (AL), la conversión de sustrato (CG), y el rendimiento (Y p/s) de Lactococcus lactis, Streptococcus salivarius y una mezcla 1:1 de ambas cepas en sustrato glucosado. Lactococcus lactis se seleccionó de 20 cepas homofermentativas aisladas de cultivos de caña de azúcar variedad CC85-92 y Streptococcus salivarius se aisló de un fermento láctico comercial. En fermentaciones llevadas a cabo con lamezcla microbiana, a 32 °C con 60 gL-1 de glucosa y pH 6,0 se obtuvo un máximo de 47,63 gL-1 de ácido láctico, conversión de glucosa de 95,4% y rendimiento en producto de 0,83 gg-1.

Production of lactic acid (LA), yield (Y p/s) and substrate conversion (SC) from Lactococcus lactis, Streptococcus salivarius and their mixtures were tested. Lactococcus lactis was selected from 20 homofermentative strains isolated from a sugar cane crop (variety CC85-92) and Streptococcus salivarius was isolated from a commercial lactic ferment. Batch fermentation experiments at 32 C with a glucose concentration of 60 gL-1 and a pH of 6,0 were carried out. A maximum of 47,63 gL-1 of lactic acid concentration, 95,4% of substrate conversion and 83 gg-1were obtained from the mixture of strains after a fermentation of 48 h.