The name 'viridans' is somewhat of a misnomer, as many species do not produce any hemolysis on blood agar. Identification of VGS to the species level can be difficult, and phenotypic identification is not always accurate. Phenotypic and biochemical identification This mechanism underlies their ability to cause subacute valvular heart disease following their introduction into the bloodstream (e.g., following dental extraction). Viridans streptococci have the unique ability to synthesize dextrans from glucose, which allows them to adhere to fibrin- platelet aggregates at damaged heart valves. Viridans streptococci are identified in cases of neonatal infections. They are the most common causes of subacute bacterial endocarditis. If they are introduced into the bloodstream, they have the potential of causing endocarditis, in particular in individuals with damaged heart valves. Others may be involved in other mouth or gingival infections as pericoronitis. sanguinis is also another potential cause. mutans, is the cause of dental caries in most cases and populations. The organisms are most abundant in the mouth, and one member of the group, S. pneumoniae or the Lancefield antigens of the pyogenic members of the genus. Viridans streptococci can be differentiated from Streptococcus pneumoniae using an optochin test, as viridans streptococci are optochin-resistant they also lack either the polysaccharide-based capsule typical of S. These species possess no Lancefield antigens.

The pseudo- taxonomic term 'Streptococcus viridans' is often used to refer to this group of species, but writers who do not like to use the pseudotaxonomic term (which treats a group of species as if they were one species) prefer the terms viridans streptococci, viridans group streptococci ( VGS), or viridans streptococcal species.

The viridans streptococci are a large group of commensal streptococcal Gram-positive bacteria species that are О±-hemolytic, producing a green coloration on blood agar plates (hence the name 'viridans', from Latin 'vДrДdis', green).

Strep pyogenes sketchy micro