All articles starting with S

Streptocarpus

Streptocarpus (Cape primrose), genus of ~160 African and Madagascan herbs in Gesneriaceae, type species S. rexii (1828); since 2015 includes African violets (Saintpaulia), with twisted capsules and major horticultural importance.

Streptocarpus ionanthus

Streptocarpus ionanthus, the African violet (formerly Saintpaulia ionantha), is a lithophytic Gesneriaceae herb native to Kenya and Tanzania, divided into nine subspecies, widely cultivated as an ornamental houseplant.

Streptococcal ecthyma

Streptococcal ecthyma (ICD-11 1B73.0), also called deep impetigo, is a dermal ulcerative skin infection caused by group A Streptococcus pyogenes, often with Staphylococcus aureus, treated with 7-day oral antibiotics.

Streptococcal necrotising fasciitis

Streptococcal necrotising fasciitis, or type II necrotizing fasciitis (hemolytic streptococcal gangrene), is a rapidly progressive Streptococcus pyogenes infection destroying fascia and fat, treated with urgent debridement plus penicillin and clindamycin, with 15-20% mortality.

Streptococcal pharyngitis

Streptococcal pharyngitis (strep throat), oropharynx infection by Streptococcus pyogenes (group A strep), causes 20-30% of childhood sore throats; treated with penicillin, which faces no reported GAS resistance; key complication is rheumatic fever.

Streptococcus

Streptococcus: genus of chain-forming Gram-positive cocci including S. pyogenes (group A strep), S. pneumoniae (pneumococcus), and S. agalactiae (group B strep), causing pharyngitis, pneumonia, meningitis, and neonatal sepsis.

Streptococcus agalactiae

Streptococcus agalactiae, or Group B Streptococcus (GBS), is a Gram-positive bacterium colonizing about a third of adults, the leading cause of neonatal sepsis and meningitis, and a major pregnancy pathogen; no licensed vaccine exists yet.

Streptococcus anginosus

Streptococcus anginosus, formerly confused with "Streptococcus milleri", is a viridans streptococcus of the SAG group (with S. constellatus and S. intermedius), a mucosal commensal causing abscesses, bacteremia, and endocarditis.

Streptococcus bovis

Streptococcus bovis, a Lancefield group D streptococcus, is now mostly renamed Streptococcus gallolyticus within the SBSEC; known for infective endocarditis and strong association with colorectal cancer and neoplasia.

Streptococcus equi

Streptococcus equi, a Lancefield group C streptococcus with subspecies equi, zooepidemicus, and ruminatorum; subsp. equi causes equine strangles, while zooepidemicus is an opportunistic, zoonotic commensal from which S. equi evolved.

Streptococcus gordonii

Streptococcus gordonii, a gram-positive alpha-hemolytic viridans group streptococcus, is a pioneer colonizer of dental plaque with adhesins SspA/B, GspB, and Hsa; it inhibits S. mutans via hydrogen peroxide but can cause infective endocarditis.

Streptococcus iniae

Streptococcus iniae (syn. S. shiloi) is a Gram-positive, beta-hemolytic fish pathogen first isolated from an Amazon freshwater dolphin in 1976; it causes streptococcosis in farmed finfish and opportunistic human cellulitis via fish-handling wounds.

Streptococcus intermedius

Streptococcus intermedius, a Gram-positive member of the Streptococcus anginosus (milleri) group, is an oral commensal and opportunistic pathogen best known for brain and liver abscesses, with species-specific toxins intermedilysin and NanA.

Streptococcus mitis

Streptococcus mitis (Andrewes and Horder 1906) is a gram-positive, alpha-hemolytic oral commensal of the mitis group of viridans streptococci, a leading cause of viridans streptococcal bacteremia and endocarditis, with boundaries against S. oralis redrawn by 2019 and 2025 whole-genome studies.

Streptococcus mutans

Streptococcus mutans, oral bacterium first isolated by J. K. Clarke in 1924, the species most strongly associated with dental caries; forms sucrose-glucan biofilms, produces lactic acid, and tolerates acid, though its essential causal role is debated.

Streptococcus oralis

Streptococcus oralis (Bridge and Sneath 1982), an alpha-hemolytic viridans streptococcus of the S. mitis group, abundant oral commensal and early dental plaque colonizer; opportunistic cause of bacteremia and infective endocarditis; three subspecies; hard to distinguish from S. mitis.

Streptococcus pneumoniae

Streptococcus pneumoniae, also known as the pneumococcus, is a lancet-shaped Gram-positive bacterium colonizing the human nose and throat, and a leading cause of pneumonia, meningitis, and bacteremia worldwide.

Streptococcus pyogenes

Streptococcus pyogenes, or group A Streptococcus (GAS), is a human-only Gram-positive, beta-hemolytic bacterium causing strep throat, scarlet fever, necrotizing fasciitis, toxic shock, and rheumatic heart disease, with over 500,000 deaths yearly and no licensed vaccine.

Streptococcus salivarius

Streptococcus salivarius, an oral commensal streptococcus of the mouth and upper respiratory tract; strains K12 and M18 produce salivaricin bacteriocins against Streptococcus pyogenes and are used as oral probiotics for throat, ear, and dental health.

Streptococcus salivarius K12

Streptococcus salivarius K12 (BLIS K12), an oral probiotic strain from a healthy New Zealand child, producing salivaricin lantibiotics; GRAS in the US since 2016, with mixed clinical evidence for sore throat and otitis media prevention.

Streptococcus salivarius M18

Streptococcus salivarius M18 (BLIS M18, DSM 14865) is an oral probiotic bacteriocin-producing strain targeting Streptococcus mutans; GRAS (GRN 807, 2019) and tested in gingivitis and caries trials.

Streptococcus sanguis

Streptococcus sanguis (correctly S. sanguinis), White and Niven 1946, is a gram-positive viridans group streptococcus, a pioneer colonizer of dental plaque and a leading cause of subacute bacterial endocarditis.

Streptococcus sobrinus

Streptococcus sobrinus, a gram-positive viridans/mutans-group streptococcus (serotypes d, g) from human tooth surfaces, cariogenic in animals; type strain SL1 (ATCC 33478, DSM 20742), named by Coykendall 1983.

Streptococcus thermophilus

Streptococcus thermophilus is a thermophilic, homofermentative lactic acid bacterium and yogurt starter culture paired with Lactobacillus delbrueckii subsp. bulgaricus; EFSA QPS-listed, distinct from S. salivarius per 2025 genomics.

Streptokinase (drug)

Streptokinase, a 47 kDa protein from beta-hemolytic streptococci (S. equisimilis H46A), is the first plasminogen-activator thrombolytic drug, discovered by Tillett in 1933, dosed at 1.5 million IU IV, and still the low-cost (~US$200) clot-buster of developing countries.

Streptokinase (gene)

Streptokinase gene (ska): streptococcal gene encoding the 414-amino-acid plasminogen activator streptokinase; beta-domain polymorphism linked to glomerulonephritis; H46A allele source of commercial thrombolytic.

Streptomyces

Streptomyces: filamentous Gram-positive soil actinobacteria, 1,240 species as of 2024, producing about half of clinically used antibiotics including streptomycin from S. griseus; model species S. coelicolor with over 20 cryptic biosynthetic gene clusters.

Streptomyces coelicolor

Streptomyces coelicolor A3(2), the model streptomycete: filamentous Gram-positive soil bacterium with an 8.67 Mb linear chromosome, 7,825 genes, and antibiotics actinorhodin, undecylprodigiosin, CDA, and methylenomycin.

Streptomyces griseus

Streptomyces griseus (Actinomyces griseus) is a Gram-positive filamentous soil bacterium, family Streptomycetaceae, NCBI taxon 1911, that produces streptomycin, the first aminoglycoside antibiotic and first tuberculosis drug, discovered at Rutgers in 1943.