what group is streptococcus salivarius

What is Streptococcus salivarius?

Streptococcus salivarius is a species of spherical, gram-positive, facultative anaerobic bacteria that is both catalase and oxidase negative. S. salivarius colonizes (usually in chains) the oral cavity and upper respiratory tract of humans just a few hours after birth, making further exposure to the bacteria harmless in most circumstances.

Is Streptococcus salivarius catalase positive or negative?

Streptococcus salivarius is a species of spherical, gram-positive, facultative anaerobic bacteria that is both catalase and oxidase negative. S. salivarius colonizes (usually in chains) the oral cavity and upper respiratory tract

What are the groups of Streptococcus?

Streptococci are subdivided into groups by antibodies that recognize surface antigens (figure 4). These groups may include one or more species. The most important groupable streptococci are A, B and D.

Is Staphylococcus salivarius a commensal or a pathogen?

S. salivarius and S. vestibularis are commensal organisms that may occasionally cause opportunistic infections in humans, whereas S. thermophilus is a food bacterium widely used in dairy production. We developed Multilocus sequence typing (MLST) and comparative genomic analysis to confirm the clear separation of these three species.

Is Streptococcus salivarius a Viridans strep?

The viridans streptococci, and in particular the species of the mitis and salivarius groups, are dominant members of the resident microbiota of the oral cavity and pharynx in all age groups. They play an important role by inhibiting the colonization of many pathogens, including pyogenic streptococci.

Is Streptococcus A Salivarius pathogen?

Streptococcus salivarius is a Gram-positive bacterium that colonizes the human oral cavity throughout the host's life and is generally associated with health [18]. S. salivarius K12 and M18 have in vitro inhibitory activity against another oral-pathogen, Streptococcus pyogenes [19].

What does Streptococcus salivarius produce?

Streptococcus salivarius K12 (BLIS K12) is a probiotic strain producing the bacteriocins salivaricin A2 and salivaricin B, both of which strongly antagonize the growth of Streptococcus pyogenes, the most important bacterial cause of pharyngeal infections in humans.

Where is Streptococcus salivarius located?

human oral cavityStreptococcus salivarius is a commensal species commonly found in the human oral cavity and digestive tract, although it is also associated with human infections such as meningitis, endocarditis, and bacteremia.

Is Streptococcus salivarius positive or negative?

gram positive bacteriumStreptococcus salivarius is a gram positive bacterium found as part of the normal human oral microflora, predominantly colonising the tongue. Streptococcus salivarius K12 (isolated from the saliva of a healthy child) is a probiotic intended for use in oral cavity.

What is Streptococcus salivarius K12?

Streptococcus salivarius K12 is an oral probiotic strain releasing two lantibiotics (salivaricin A2 and salivaricin B) that antagonize the growth of S. pyogenes, the most important bacterial cause of pharyngeal infections in humans also affected by episodes of acute otitis media.

What is Streptococcus salivarius used for?

The S. salivarius TOVE-R strain has been reported to be a successful antagonist of virulent streptococci involved in tooth decay or pharyngitis, such as Streptococcus mutans, Streptococcus sobrinus, and Streptococcus pyogenes (19), or pathogens involved in periodontitis (20, 21).

Is Streptococcus salivarius beta hemolytic?

Thirty strains of Streptococcus salivarius were beta-haemolytic when initially isolated from throat swabs and, because they were also bacitracin sensitive, they could be confused with the pathogenic Streptococcus pyogenes on primary culture plates.

Does Streptococcus salivarius cause dental caries?

S. salivarius has been associated with caries in clinical studies using DNA-based methods [11], [37]. In the present study the salivarius group was significantly associated with caries, and appeared to be the primary pathogen in some subjects (Figure 3).

Is Streptococcus salivarius gram-positive cocci?

Streptococcus salivarius is a gram-positive, facultative anaerobic microorganism that is found in the oral cavity and upper respiratory tract of human beings. S.

What probiotic kills strep?

[9] Studies based on the use of the intestinal probiotics Lactobacillus rhamnosus GG,[10] Lactobacillus reuteri, and Bifidobacterium[11] have each reported achieving reduced levels of Streptococcus mutans.

What is the colony morphology of Streptococcus salivarius?

Bacteria Collection: Streptococcus salivarius subsp. salivarius Additional InformationFermentation Tests Text:Sorbitol : -,Sucrose : +Colony Appearance Text:smooth : Yes,shiny : YesColony Color Text:grey : YesColony Text:circular : Yes,convex : Yes,entire : YesColony Diameter:?11 more rows

Is Streptococcus salivarius hemolytic?

Streptococcus pneumoniae, Streptococcus salivarius, viridans are referred to collectively as viridans streptococci, a name derived from viridis (Latin for "green"), referring to the green pigment formed by the partial, α-hemolysis of blood agar.

Does Streptococcus salivarius cause dental caries?

S. salivarius has been associated with caries in clinical studies using DNA-based methods [11], [37]. In the present study the salivarius group was significantly associated with caries, and appeared to be the primary pathogen in some subjects (Figure 3).

Does Streptococcus salivarius form endospores?

It tests negative for cytochrome, oxidase, and catalase, and positive for alpha-hemolytic activity. It is non-motile and does not form endospores.

What probiotic kills strep?

[9] Studies based on the use of the intestinal probiotics Lactobacillus rhamnosus GG,[10] Lactobacillus reuteri, and Bifidobacterium[11] have each reported achieving reduced levels of Streptococcus mutans.

What is the name of the bacteria that colonizes the pharyngeal cavity?

Streptococcus salivarius K12 (BLIS K12) is a probiotic strain producing the bacteriocins salivaricin A2 and salivaricin B, both of which strongly antagonize the growth of Streptococcus pyogenes, the most important bacterial cause of pharyngeal infections in humans. It successfully colonizes and exhibits persistence in the oral cavity, ...

What is the relationship between Sc. thermophilus and Lactobacillus?

thermophilus and a Lactobacillus (particulary Lb. bulgaricus ), there being an associative growth relationship between them: Sc. thermophilus produces formate that stimulates Lb. bulgaricus, and Lb. bulgaricus produces amino acids that stimulate Sc. thermophilus.

What is VSL-3?

VSL-3 is a proprietary mixture of Lactobacillus acidophilus, Lactobacillus bulgaricus, Lactobacillus casei, Lactobacillus plantarum, Bifidobacteriium brevis, Bifidobacteriium infantis, Bifidobacteriium longum, and Streptococcus salivarius ssp thermophilus, supplied in sachets containing 900 billion organisms each. When added to therapy with the 5-ASA derivative balsalazide, VSL-3 (one sachet twice a day) induced faster remission of active UC than balsalazide or mesalazine alone. 131 In an uncontrolled trial, two sachets of VSL-3 twice a day for 6 weeks as monotherapy yielded clinical and endoscopic remission of mild-to-moderate UC in 54% of patients treated. 132 VSL-3 also prevents relapse of pouchitis (postcolectomy inflammation of the ileal pouch), 133 with two sachets once a day producing remission rates far better than placebo over a 1-year period. 134 A survey done at the Cleveland Clinic, however, found poor compliance with this therapy in patients not participating in clinical trials. 135

Which bacteria produce lactose?

Yogurt bacteria, Streptococcus salivarius subsp. thermophilus and L. delbrueckii sp. bulgaricus, produce the enzyme, lactose (beta-galactosidase), which hydrolyzes lactose to glucose and galactose. It is possible that they supply preformed lactase to the gut, thus allowing digestion of lactose.

What is the oral flora of an abscess?

The oral flora involved in abscesses of odontogenic origin is similar to that in adults. At birth, the oral cavity is sterile and uncolonized, but within the first few days of life it begins to become colonized with Streptococcus salivarius and subsequently the other bacteria that comprise those found in the adult population (e.g., Staphylococcus, Actinomyces, Nocardia, Bacteroides species). 17 The eruption of dentition allows for the anaerobic bacteria to populate the gingival sulci, and also allows Streptococcus mutans and Streptococcus sanguinis (responsible for a large portion of dental caries) to colonize the enamel. Untreated dental caries that progresses to the pulp creates a portal of entry into the root apices, alveolus, maxilla, mandible, and surrounding spaces as the disease progresses. Infections in the submandibular and lingual spaces in a child are infrequent, but necessitate the close attention of the treating team to ensure that the smaller, developing airway is not compromised ( Figure 29-2 ). Incision and drainage is recommended for the definitive abscess, as well as extraction or treatment of the offending tooth. Patients with developing, partially erupted third molars are at risk of developing pericoronitis and associated abscesses (most notably the adjacent pterygomandibular space). Impacted teeth that present an impediment to maintaining proper oral hygiene should be extracted, preferably before the development of infections or complications.

Is S. thermophilus a species?

Taxonomic placement of S. thermophilus is representative of its recent deviation from a related ancestor. Originally S. thermophilus was considered a species in its own right by Orla-Jensen in 1919 [4]. S. thermophilus and Streptococcus salivarius are highly related (99% at 16S rRNA gene level). Therefore, there is still contention as to whether the two should be included as the same species or not. The taxonomic status of S. thermophilus had been in question for several years and some investigators proposed that it should be a subspecies of S. salivarius. In 1984, DNA–DNA hybridization experiments placed S. thermophilus under the umbrella of the salivarius species, as S. salivarius subspecies thermophilus [5]. Schleifer et al. conducted further DNA–DNA reassociation experiments under stringent conditions and determined that these strains probably deserved separate full species status and suggested that the name should be shifted back to its former one, though it is still widely reported as S. salivarius ssp. thermophilus [4]. This has not been fully ratified by taxonomic committees.

Which bacteria produce lactose?

Yogurt bacteria, Streptococcus salivarius subsp. thermophilus and L. delbrueckii sp. bulgaricus, produce the enzyme, lactose (beta-galactosidase), which hydrolyzes lactose to glucose and galactose. It is possible that they supply preformed lactase to the gut, thus allowing digestion of lactose.

Which family of bacteria causes mastitis?

Some species of the family Micrococc aceae (which is closely related, from a taxonomical point of view, to family Staphylococcaceae) may cause mastitis. They include Rothia dentocariosa, Rothia mucilaginosa, Kocuria rosea, and Kocuria kristinae, which are often involved in human opportunistic infections.

What are the effects of betel nuts on Streptococcus mutans?

Betel nuts have an inhibitory effect on the growth of Streptococcus mutans and Fusobacterium nucleatum, and on glucan formation.

What is the antimicrobial activity of Psoralea corylifolia Linn?

Bakuchiol, which is isolated from the seeds and leaves of Psoralea corylifolia Linn, shows antimicrobial activity against oral pathogens.

Is Streptococcus epidermidis a nosocomial pathogen?

Among CNS, Streptococcus epidermidis is the species most commonly associated with lactational mastitis in women ( Thomsen et al., 1985; Delgado et al., 2008, 2009b; Jiménez et al., 2008a; Arroyo et al., 2010 ). Normally, it is a commensal inhabitant of healthy human skin and mucosal surfaces but, also, it is a common nosocomial pathogen ( Otto, 2009 ). Living at the edge between commensalism and pathogenicity, S. epidermidis has developed interesting strategies to transform into a notorious pathogen ( Schoenfelder et al., 2010 ). Similarly as in humans, CNS have become the most common mastitis-causing agents in ruminants and other mammals in many countries ( Zhang and Maddox, 2000; Pyörälä and Taponen, 2009; Thorberg et al., 2009; Park et al., 2011a ). Although CNS are not as pathogenic as S. aureus and infection mostly remains subacute or subclinical, CNS are relevant as they can cause persistent infections, which result in increased milk SCCs, tissue damage, and decreased milk quality and secretion.

Where is S. salivarius found?

Ecology. S. salivarius is found in the upper respiratory tract and oral cavity of the human body. While the bacterium is part of the normal flora in those environments, its entrance to the bloodstream causes it to become pathogenic (3).

What is salivarius?

S. salivarius is a facultative anaerobe (6) . Facultative anaerobes perform respiration in the presence of oxygen. In situations where oxygen is not readily available, facultative anaerobes can switch to fermentation or anaerobic respiration to generate ATP.

Why is salivarius purple?

salivarius is a Gram-positive cocci so Gram stain results would show a purple stain under the microscope due to crystal-violet dye’s affinity to the thick peptidoglycan layer. S. salivarius contains a peptidoglycan layer specifically called murein, which provides protection and rigidity, and helps shape the cell.

Does salivarius cause sepsis?

S. salivarius has been linked to cases of sepsis in people with neutropenia, a disease associated with a depleted level of white blood cells in the body (3). Sepsis occurs when the immune system becomes compromised, which allows the bacteria to attack when immune cells are weakened.

Does salivarius have heat resistant genes?

It is unknown whether the similar gene found in S. sa livarius have the same heat-resistant properties.

Is S. salivarius a Gram positive or negative?

S. salivarius is a spherical, Gram-positive, facultative anaerobic commensal bacterium that is both catalase and oxidase negative. As one of the first colonizers of the human oral cavity, upper respiratory tract, and gut after birth, S. salivarius is thought to contribute to immune homeostasis and regulate inflammatory response. Thus, the bacterium is most often harmless but considered an opportunistic pathogen (1).

Is salivarius good for ear infections?

S. salivarius K12 also has a beneficial effect on ear health in humans. A bacteriotherapy trial has been conducted which tested the potential benefits of S. salivarius by administering a nasal spray containing a strain of S. salivarius to children with recurrent acute otitis media, or middle ear infection (10).

What is the name of the group of streptococci?

The salivarius group of streptococci is of particular importance for humans. This group consists of three genetically similar species, Streptococcus salivarius, Streptococcus vestibularis and Streptococcus thermophilus. S. salivarius and S. vestibularis are commensal organisms that may occasionally …

What are the three species of streptococci?

This group consists of three genetically similar species, Streptococcus salivarius, Streptococcus vestibularis and Streptococcus thermophilus. S. salivarius and S. vestibularis are commensal organisms that may occasionally cause opportunistic infections in humans, whereas S. thermophilus is a food bacterium widely used in dairy production. We developed Multilocus sequence typing (MLST) and comparative genomic analysis to confirm the clear separation of these three species. These analyses also identified a subgroup of four strains, with a core genome diverging by about 10%, in terms of its nucleotide sequence, from that of S. salivarius sensu stricto. S. thermophilus species displays a low level of nucleotide variability, due to its recent emergence with the development of agriculture. By contrast, nucleotide variability is high in the other two species of the salivarius group, reflecting their long-standing association with humans. The species of the salivarius group have genome sizes ranging from the smallest (∼ 1.7 Mb for S. thermophilus) to the largest (∼ 2.3 Mb for S. salivarius) among streptococci, reflecting genome reduction linked to a narrow, nutritionally rich environment for S. thermophilus, and natural, more competitive niches for the other two species. Analyses of genomic content have indicated that the core genes of S. salivarius account for about two thirds of the genome, indicating considerable variability of gene content and differences in potential adaptive features. Furthermore, we showed that the genome of this species is exceptionally rich in genes encoding surface factors, glycosyltransferases and response regulators. Evidence of widespread genetic exchanges was obtained, probably involving a natural competence system and the presence of diverse mobile elements. However, although the S. salivarius strains studied were isolated from several human body-related sites (all levels of the digestive tract, skin, breast milk, and body fluids) and included clinical strains, no genetic or genomic niche-specific features could be identified to discriminate specific group.

How much of the genome does S. salivarius have?

Analyses of genomic content have indicated that the core genes of S. salivarius account for about two thirds of the genome, indicating considerable variability of gene content and differences in potential adaptive features.

Why is the nucleotide variability low in S thermophilus?

S. thermophilus species displays a low level of nucleotide variability, due to its recent emergence with the development of agriculture. By contrast, nucleotide variability is high in the other two species of the salivarius group, reflecting their long-standing association with humans.

Content

Streptococcus salivarius is a Gram positive, spherical (coconut) bacteria that colonizes the oral cavity and intestine of humans after birth. For this reason, this bacterium can be part of the establishment of immune homeostasis, in the ecology of the digestive and oral tracts.

characteristics

Streptococcus salivarius It is a Gram positive bacterium, with a cocci morphology of more or less 2 µm. They are grouped in pairs or in short chains of cocci.

Morphology

Streptococcus salivarius belongs to the viridans group; It is the main microorganism that colonizes the tongue, the upper respiratory tract and the oral mucosa.

Culture

The optimal growth temperature for S. salivarius It is 37 ° C, so it grows perfectly in the mucosa of human beings. It grows in blood agar culture medium.

Diseases it causes

Streptococcus salivarius it does not normally have a high potential as a virulent microorganism. In fact, being isolated from blood cultures indicated that there was some contamination of the sample.

Associated risks

This microorganism is not transmitted from person to person, nor is an incubation period known. Furthermore, no vector is known, nor any zoonoses.

Treatment

Treatment is usually done with penicillin and erythromycin (for people who are allergic to penicillin), as these bacteria are sensitive to these drugs. For its part, erythromycin is an antibiotic of the macrolide family, and is synthesized by Streptomyces erythraeus.

What is group A streptococci?

Group A streptococci: Lancefield’s group A Streptococcus is also known as Streptococcus pyogenes. Identification is confirmed by demonstrating the presence of the group A antigen on the streptococcal cells. All S. pyogenes have group A antigen; but, not all streptococci with group A antigen are S. pyogenes. Some strains of S. anginosus and S. dysgalactiae subsp. equisimilis may also have group A antigen. Non-pyogenes strains grow more slowly and form smaller colonies than do S. pyogenes strains. If the ß-hemolytic colonies appear small and growth is delayed or carbon dioxide is required for growth or the group A strain is PYRase negative the microbiologist should suspect that the strain may be S. anginous or S. dysgalactiae subsp. equisimilis, regardless of group reaction. When this occurs the strain should be tested for voges-proskauer (VP) reaction. See Table 2, for correct identification.

Why are there so many genera in the streptococcus reference laboratory?

The following genera are identified in Streptococcus Reference Laboratory. There are three major reasons for the increase in number of genera that clinical microbiologist must identify. First the genetic studies by taxonomists have clarified the relationship of some genera. The enterococci and lactococci were split from the Streptococcus genus. DNA homology studies have indicated that these two genera are separate and distinct entities. In addition the vagococci were split from the Lactococcus genus on the same basis. The tetragenococci were split from the Pediococcus genus because it too is genetically different from the other members of the genus.

What is the origin of gram positive cocci?

The origin of this genus is from a collection of viridans-like streptococci that most closely resembled Streptococcus uberis. What makes Globicatella distinct from the viridans streptococci is that all the Globicatella strains were PYR positive, LAP negative and grow in broth containing 6.5% NaCl while all viridans species are PYR negative, LAP positive and fail to grow in 6.5% NaCl. All strains identified to date have been sensitive to vancomycin, PYR positive, LAP negative, grow in 6.5% NaCl broth, do not grow at 10ΕC or 45ΕC, are nonmotile, and are α-hemolytic.

Why were the vagococci and pediococci split?

The tetragenococci were split from the Pediococcus genus because it too is genetically different from the other members of the genus. The Leuconostoc s and pediococci were considered non-pathogenic until the mid 1980s.

What are the two species of helocococci?

H. kurzii is the only one isolated from humans. These bacteria have been isolated from wound infections. Like the Alloiococci and Gemella e these bacteria grow very slowly on blood agar media. The physiologic characteristics of helocococci are similar to the aerococci in that they are PYR positive, LAP negative, and grow in broth containing 6.5% NaCl. These bacteria grow more slowly and are not α-hemolytic on blood agar while the aerococci grow readily and are α-hemolytic on blood agar. Like the Aerococci these strains are vancomycin sensitive, do not form gas in MRS broth and fail to grow at 10ΕC and 45ΕC. All isolates have been non-motile.

What are ß-hemolytic streptococci?

There are other ß-hemolytic streptococci but they are rarely found in human infections. Some of the strains are associated with infections of swine and they have specific group antigens. Using DNA-DNA homology the taxonomist have suggested that those ß-hemolytic strains with group E, P, U, V, and other experimental group antigens be called S. porcinus. ß-hemolytic strains with group L antigen have been associated with avian sources (chicken), it is suggested that these strains be called S. dysgalactiae. ß-hemolytic strains with group M antigen are not well studied and there is no suggested taxonomic name for these strains. A ß-hemolytic strain with a yet to be named group antigen (suggested X) isolated from fresh water dolphins, and occasionally in human infections, is called S. iniae. This bacterium may be submitted as a group A streptococci because it may react with the group A antibody in the latex slide agglutination assay. It is also PYRase positive but is not sensitive to bacitracin. Whenever a latex agglutination group A positive bacterium is submitted that is not sensitive to bacitracin the group reaction should be confirmed using the Lancefield extraction procedure.

How to separate bacteria into genera?

Initial separation into the appropriate genera is accomplished by determining the physiologic characteristics listed in Table 1. The extent to which each bacterial strain is tested is dependent upon the source of the strain . If the strain is from a normally sterile-site then all the tests listed below should be applied. There are some instances where all the tests do not need to be applied; i.e., the beta-hemolytic streptococci and the pneumococci. There are specific tests that clinical microbiologist perform when these pathogens are suspected. These situations and tests will be discussed in the section on streptococci.

Why is the nomenclature and taxonomy of streptococci confusing?

Nomenclature and taxonomy of streptococci confusing because of many historical efforts at describing the class. Often described by 5% sheep blood agar hemolysis (1902) or Lancefield carbohydrate group antigens (1933). Group A streptococci: cause complete hemolysis/lysis of red cells in blood agar media around/under colonies caused by streptolysin ...

What is the name of the group of streptococci that causes complete hemolysis?

Group A streptococci: cause complete hemolysis/lysis of red cells in blood agar media around/under colonies caused by streptolysin (exotoxin), so called β-hemolysis . See separate module for details on this organism.

Classification

Description and Significance

• S. salivarius is a spherical, Gram-positive, facultative anaerobic commensal bacterium that is both catalase and oxidase negative. As one of the first colonizers of the human oral cavity, upper respiratory tract, and gut after birth, S. salivarius is thought to contribute to immune homeostasis and regulate inflammatory response. Thus, the bacterium...

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Genome Structure

Cell Structure

Metabolic Processes

Ecology

Pathology

Current Research

References