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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.
Streptomyces lividans
Streptomyces lividans, a high-GC Gram-positive soil actinomycete related to S. coelicolor, is a risk-group-1 cloning and protein-secretion host lacking restriction of methylated DNA, with Sec and Tat secretion routes and largely silent antibiotic gene clusters.
Streptomyces subtilisin inhibitor
Streptomyces subtilisin inhibitor (SSI), MEROPS family I16, is a dimeric 113-residue bacterial protease inhibitor from Streptomyces albogriseolus S-3253 that inhibits subtilisin, trypsin, plasmin, kexin, and griselysin via a Met73 reactive site.
Streptomycin
Streptomycin, a 1944 aminoglycoside from Streptomyces griseus and the first antibiotic effective against tuberculosis, now a second-line injectable TB and endocarditis drug dosed 15 mg/kg IM, limited by ototoxicity and rrs/gidB resistance.
Streptopelia
Streptopelia (turtle-doves) is a genus of Columbidae doves of Europe, Asia, and Africa, with 15 recognized species, weak molecular monophyly, a critically declining turtle dove, and the invasive Eurasian collared-dove.
Streptopelia senegalensis
Streptopelia senegalensis, the laughing dove (also Spilopelia senegalensis, palm dove), a small Columbidae dove of Africa, Arabia, and South Asia; IUCN Least Concern, expanding range, two-egg clutches, CITES Appendix III Ghana.
Streptozocin
Streptozocin, also spelled streptozotocin (STZ), is a nitrosourea chemotherapy drug produced by the bacterium Streptomyces achromogenes and sold as Zanosar for pancreatic neuroendocrine tumors.
Stresa Front
Stresa Front: April 14, 1935 agreement of Britain, France, and Italy at Stresa against German rearmament; collapsed after the Anglo-German Naval Agreement and Italy's invasion of Ethiopia.
Stress (biology)
Stress (biology): the physiological response of organisms to stressors that disturb homeostasis. Also eustress/distress, allostasis, allostatic load, HPA axis, and cellular stress responses from Selye's 1936 work onward.
Stress (linguistics)
Stress (linguistics) is relative phonetic prominence of a syllable in a word or a word in a phrase, cued by pitch, duration, intensity, vowel quality, and spectral balance. Its placement can be fixed, weight-sensitive, or lexically contrastive, and it interacts with tone and pitch accent.
Stress (mechanics)
Stress, also called mechanical or internal stress, is the internal force per unit area within a deformable body, described by the Cauchy stress tensor and measured in pascals.
Stress concentration
Stress concentration, also known as a stress riser or stress raiser, is the localized increase of stress around a discontinuity such as a hole or notch in a loaded solid, measured by a dimensionless factor.
Stress corrosion cracking
Stress corrosion cracking (SCC) is crack growth in metal under tensile stress, applied or residual, in a corrosive environment, causing large strength loss with little metal loss.
Stress echocardiography
Stress echocardiography, including dobutamine stress echocardiography, is a cardiac ultrasound method that images left ventricular wall motion during exercise or pharmacological stress to detect coronary artery disease.
Stress electrocardiography
Stress electrocardiography, or exercise ECG testing, records a continuous electrocardiogram during treadmill or cycle exercise to detect myocardial ischemia and assess prognosis in known or suspected coronary artery disease.
Stress fracture
Stress fracture: a bone crack from repetitive overuse loading on normal bone, common in athletes and military recruits. MRI is the diagnostic gold standard; sites are classified low- or high-risk by blood supply and tensile load, guiding rest versus surgery.
Stress grading
Stress grading, also called field grading or electric field grading, controls the electric field distribution within or around a high-voltage device, most commonly in the terminations and joints of power cables.
Stress granule
Stress granule: membraneless cytoplasmic RNA-protein condensate of stalled translation initiation complexes, formed reversibly via G3BP1-driven liquid-liquid phase separation during stress; linked to ALS, Alzheimer's, cancer, and blocked by SARS-CoV-2 N and NSP3.
Stress incontinence
Stress incontinence (stress urinary incontinence, SUI) is involuntary urine leakage during coughing, exertion, or sneezing, the most common incontinence type in women; treated first with pelvic floor muscle training and weight loss, then slings or colposuspension.
Stress intensity factor
The stress intensity factor (SIF), denoted K, characterizes the stress field at a sharp crack tip in a linear elastic body, combining applied stress, crack size, and geometry.
Stress management
Stress management is the use of techniques such as relaxation training, breathing exercises, and mindfulness to cope with stressful situations and with the stressed condition itself.
Stress path
A stress path is the trajectory that a soil element's stress state follows during loading, unloading, or reloading, plotted on a p-q diagram in soil mechanics.