Salegentibacter
holothuriorum - mishustinae - salegens

Salinivibrio
costicola

Salipiger
mucosus

Salmonella
enterica

Saprospira
grandis

Scardovia
inopinata

Schlegelella
thermodepolymerans

Serratia
ficaria - fonticola - grimesii - marcescens - plymuthica - proteamaculans - quinivorans - rubidaea - sp. - ureilytica

Shewanella
algae - baltica - denitrificans - fidelis - frigidimarina - hanedai - japonica - livingstonensis - marinintestina - oneidensis - putrefaciens - sairae - schlegeliana - violacea

Shigella
flexneri - sonnei

Shinella
zoogloeoides

Simonsiella
crassa - muelleri - steedae

Simplicispira
psychrophila

Sinorhizobium
americanum - arboris - fredii - kostiense - medicae - meliloti - morelense - saheli - terangae - xinjiangense

Sphaerotilus
natans

Sphingobacterium
faecium - multivorum - sp. - spiritivorum - thalpophilum

Sphingobium
chlorophenolicum - herbicidovorans - yanoikuyae

Sphingomonas
abaci - adhaesiva - aerolata - asaccharolytica - aurantiaca - cloacae - echinoides - faeni - mali - melonis - panni - parapaucimobilis - paucimobilis - phyllosphaerae - pruni - sanguinis - sp. - suberifaciens - trueperi

Sphingopyxis
alaskensis - chilensis - macrogoltabida - terrae

Spirosoma
linguale

Sporocytophaga
myxococcoides

Sporolactobacillus
inulinus - kofuensis - nakayamae - terrae

Sporosarcina
globispora - pasteurii - psychrophila - ureae

Staleya
guttiformis

Stanierella
latercula

Staphylococcus
arlettae - aureus - capitis - caprae - carnosus - chromogenes - delphini - epidermidis - equorum - felis - gallinarum - haemolyticus - hominis - hyicus - intermedius - kloosii - lentus - lugdunensis - lutrae - piscifermentans - pseudintermedius - saprophyticus - schleiferi - simiae - succinus - warneri - xylosus

Stappia
aggregata

Stenotrophomonas
acidaminiphila - maltophilia - nitritireducens

Streptococcus
acidominimus - agalactiae - alactolyticus - anginosus - australis - bovis - canis - constellatus - criceti - cristatus - didelphis - downei - dysgalactiae - entericus - equi - equinus - ferus - gallinaceus - gallolyticus - gordonii - hyointestinalis - hyovaginalis - infantarius - infantis - iniae - intermedius - macacae - minor - mitis - mutans - oligofermentans - oralis - orisratti - ovis - parasanguinis - parauberis - peroris - phocae - pleomorphus - pluranimalium - pneumoniae - porcinus - pyogenes - ratti - salivarius - sanguinis - sinensis - sobrinus - sp. - suis - thermophilus - thoraltensis - uberis - urinalis - vestibularis

Streptomyces
aburaviensis - acidiscabies - albidoflavus - albus - amakusaensis - antibioticus - anulatus - atroolivaceus - aurantiacus - aurantiogriseus - aureofaciens - badius - bambergiensis - bluensis - cacaoi - caelestis - caeruleus - californicus - canus - cellulosae - chattanoogensis - chromofuscus - cinnamoneus - cyanoalbus - diastaticus - echinatus - exfoliatus - filipinensis - flaveolus - flaveus - fulvissimus - glaucescens - glauciniger - griseocarneus - griseoflavus - griseoincarnatus - griseoluteus - griseoruber - griseoviridis - griseus - halstedii - hawaiiensis - hygroscopicus - intermedius - kanamyceticus - longisporoflavus - luridiscabiei - luridus - lydicus - massasporeus - microflavus - murinus - netropsis - nigrescens - noboritoensis - nodosus - nogalater - noursei - ochraceiscleroticus - olivaceiscleroticus - olivaceoviridis - pactum - pallidus - paucisporogenes - phaeochromogenes - poonensis - prasinopilosus - prasinosporus - prunicolor - puniciscabiei - ramulosus - rimosus - rochei - scopiformis - sp. - sparsogenes - spectabilis - sulphureus - tendae - tenebrarius - thermoviolaceus - thermovulgaris - tubercidicus - varsoviensis - venezuelae - violaceoruber - violaceus - violaceusniger - viridifaciens - yerevanensis

Sulfitobacter
delicatus - dubius - mediterraneus - pontiacus

Suttonella
indologenes

Swaminathania
salitolerans