HOMD Banner
16S rRNA RefSeq: V15.23    Genomic RefSeq: V10.1
Back To Tax Table
Streptococcus mitis (HMT-677)
Taxon Description:
Heterogenous group of viridans type of streptococci that has had taxonomic revisions. Original type strain NCTC 3165 (= SK51) clustered with Streptococcus gordonii strains. Proposed NCTC 12261 be replacement type strain of S. mitis [2]. Closely related to S. pneumoniae by 16S rRNA comparisons.


Disease Associations:
Not usually attributed to disease especially oral infections.May be involved in infective endocarditis toxic shock-like syndrome and neonatal infections. Septicemias have been reported.

Prevalence and Source:
Commonly found on most surfaces in the human oral cavity and throat [1].
species/SmitisMagenta-HparaCyan.jpg Cells of Streptococcus mitis/oralis (magenta) and Haemophilus parainfluenzae (cyan) together in dental plaque.
See Perera et al. 2021

Classification:
Domain:Bacteria
Phylum:Firmicutes
Class: Bacilli
Order: Lactobacillales
Family:Streptococcaceae
Genus: Streptococcus
Species:Streptococcus mitis
Status: Named - Cultured
Type/Reference Strain: NCTC 12261
[Check LPSN.dsmz.de]
[Check Global Catalogue of Microorganisms]
Former Names or Synonyms:
Phylum: Firmicutes
16S rRNA Reference Sequences:    view in
RefSeq tree
RefSeq ID: 677_3929


Download latest 16S rRNA reference gene sequences.
Genotypic Description:
Phenotypic Characteristics:
Facultatively anaerobic Gram positive cocci approximately 1 um in diameter that grow in short or long chains in broth cultures. Carbohydrates are femented primarily to lactic acid and no gas. Catalase negative. Cell wall contains riitol teichoic acid and minimal rhamnose. Peptidoglycan type is Lys-direct. G+C content is 41 mol%.[23]2 biovars of S. mitis differ biochemically and serologically [23]
Cultivability: Alpha-hemolytic colonies (0.7- 1.2 mm diameter) on blood agar and extensive greening on chocolate agar.
Pangenome(s):
(Anvi`o-server hosted on VAMPS)		 Mitis_Group
Microbial Ecology
(Abundance/Prevalence):		 [Open Abundance/Prevalence Page for ]
Proteomics:
NCBI Taxon ID: 28037 [Link to NCBI]
PubMed Searches:
[NCBI PubMed Link]
[NCBI (Entrez) Nucleotide Link]
[NCBI (Entrez) Protein Link]
Number of
Genome Sequences:		 216 See List
Phylogenetic Trees:
View in genome tree
View in ribosome protein tree
View in 16S rRNA gene tree
References:

[1] Kilian M, Mikkelsen L, Henrichsen J. Taxonomic study of viridans Streptococci: Description of Streptococcus gordonii sp. nov. and emended descriptions of S. sanguis (White and Niven 1946), S. oralis .... Int J Syst Bacteriol. 1989 Oct;39(4):471-84.
[2] Aas JA, Paster BJ, Stokes LN, Olsen I, Dewhirst FE. Defining the normal bacterial flora of the oral cavity. J Clin Microbiol. 2005 Nov;43(11):5721-32
[3] Hardie RM. Genus Streptococcus. Bergey's Manual of Systematic Bacteriology 1986; Vol. 2, pp. 1043-1063.