Cross Index | Streptococcus |
SuperSet | Prokaryote, Eubacteria Gram Positive Cocci |
Compare | aerobes: Deinobacter grandis Deinococcus,
Marinococcus, Micrococcus,
Planococcus , Salinicoccus roseus facultative anaerobes: Aerococcus viridans, Enterococcus, Gemella haemolysans, Lactococcus Leuconostoc, Melissococcus pluton, Pediococcus, Saccharococcus thermophilus, Staphylococcus, Stomatococcus mucilaginsos, Streptococcus, Trichococcus flocculiformis, Vagococcus anaerobes Coprococcus, Peptococcus niger , Peptostreptococcus, Ruminococcus, Sarcina Catalase positive:Deinococcus, Micrococcus, Planococcus, Staphylococcus,, Stomatococcus mucilaginsosus |
Contrast | Micrococcaceae are not a coherent group. Micrococcus is closely related to Arthrobacter , Planococcus is related to Bacilluss, while the radioresistant cocci called Deinococcus have atypical Gram positive cell walls |
Subset |
Morphology | Streptococcus |
CELLULAR |
Staining | Gram-positive |
Morphology | spherical or ovoid occurring in`pairs or chains |
Motility | |
Specialized structures | Endospores are not formed |
Division |
COLONIAL |
Solid surface | Hemolytic Streptococci cause either beta hemolysis which is characterized by a sharp zone or clearing around the colony on sheep blood agar or alpha hemolysis which causes an indistinctzone of greenish discoloration |
Liquid |
Growth Parameters | Streptococcus |
PHYSIOLOGICAL |
Tropism | chemoorganotrophs |
Oxygen | Most are facultative anaerobes but some require carbon dioxide and some are anaerobes fermentative metabolism |
pH | |
Temperature | |
Requirements | |
Products | Carbohydrates are fermented to lactic acid with no gas |
Enzymes | Catalase negative |
Unique features | The streptococci can be group ed and classified serologically. The Beta hemolytic S. pyogenes is sensitive to bacitracin but some of the non hemolytic group A streptococci are also sensitive. The streptococci produce a wide range of toxins and extracellular products. |
ENVIRONMENTAL |
Habitat | |
Lifestyle | |
Pathogenicity | Many species are commensals or parasites on man or animals but some are highly pathogenic. A few are saprophytes and are found in the natural environment |
Distribution |
Genome | Streptococcus |
G+C Mol % | 34-46 |
Reference | Streptococcus |
First citation | Rosenbach,F.J.(1884) Micro-organismen bei den Wund-Infections-Krankheiten des Menschen. J.F. Bergmann, Weisbaden, pp 1-122 |
The Prokaryotes | p |
Bergey's Systematatic | p 1043 J. M. Hardie |
Bergey's Determinative | p 532 |
References |