Streptococcus alactolyticus

Streptococcus alactolyticus
Scientific classification
Domain:	Bacteria
Kingdom:	Bacillati
Phylum:	Bacillota
Class:	Bacilli
Order:	Lactobacillales
Family:	Streptococcaceae
Genus:	Streptococcus
Species:	S. alactolyticus
Binomial name
	Streptococcus alactolyticus; Farrow & Collins 1984
Type strain
	ATCC 43077 = DSM 20542

Streptococcus alactolyticus is a species of Gram-positive, facultatively anaerobic cocci that forms chains and belongs to the Streptococcus bovis/equinus complex (SBSEC). It was proposed as a novel species in 1984 when lactose-negative porcine intestinal isolates previously assigned to biotype II of Streptococcus bovis were shown by DNA–DNA hybridization and phenotypic traits to constitute a distinct taxon.¹

Etymology

The specific epithet *alactolyticus* (Latin: *a-* "without", *lactum* "milk", and *lyticus* "able to break down") refers to the species' inability to hydrolyze or ferment lactose.

Ecology

S. alactolyticus has been isolated from dogs,² pigs,³⁴ and poultry,⁵ where it is considered part of the normal microbiota.

Clinical relevance

Although uncommon, S. alactolyticus has been implicated in opportunistic human infections. Reported clinical cases include infective endocarditis,⁶ bacteremia, and neonatal sepsis. A 2020 case report described a rare instance of neonatal meningitis caused by this species, confirmed through culture and treated successfully with ampicillin and cefotaxime.⁷

References

Farrow, J. A. E.; Kruze, J.; Phillips, B. A.; Bramley, A. J.; Collins, M. D. (December 1984). "Taxonomic studies on Streptococcus bovis and Streptococcus equinus: Description of Streptococcus alactolyticus sp. nov. and Streptococcus saccharolyticus sp. nov". Systematic and Applied Microbiology. 5 (4): 467–482. Bibcode:1984SyApM...5..467F. doi:10.1016/S0723-2020(84)80004-1.
Rinkinen, M.-L.; Koort, J.-M.; Ouwehand, A. C.; Westermarck, E.; Björkroth, K. J. (15 January 2004). "Streptococcus alactolyticus is the dominating culturable lactic acid bacterium species in canine jejunum and feces of four fistulated dogs". FEMS Microbiology Letters. 230 (1): 35–39. doi:10.1016/S0378-1097(03)00851-6. hdl:1975/521. PMID 14734163.
Devriese, L. A.; Hommez, J.; Pot, B.; Haesebrouck, F. (July 1994). "Identification and composition of the streptococcal and enterococcal flora of tonsils, intestines and faeces of pigs". Journal of Applied Bacteriology. 77 (1): 31–36. doi:10.1111/j.1365-2672.1994.tb03040.x. PMID 7928781.
Jiménez, E.; Sánchez, B.; Farina, A.; Margolles, A.; Rodríguez, J. M. (2014). "Characterization of the bile and gall bladder microbiota of healthy pigs". MicrobiologyOpen. 3 (6): 937–949. doi:10.1002/mbo3.218. PMC 4263516. PMID 25336405.
Devriese, L. A.; Hommez, J.; Wijfels, R.; Haesebrouck, F. (July 1991). "Composition of the enterococcal and streptococcal intestinal flora of poultry". Journal of Applied Bacteriology. 71 (1): 46–50. doi:10.1111/j.1365-2672.1991.tb04480.x (inactive 20 July 2025). PMID 1910033.{{cite journal}}: CS1 maint: DOI inactive as of July 2025 (link)
Yiu, K. H. (2011). "Native-valve endocarditis due to Streptococcus alactolyticus: Case report and literature review". Clinical Microbiology and Infection. 17 (4): 630–632. doi:10.1111/j.1469-0691.2010.03258.x. PMID 20459438.
Park, S. J.; Yoon, L.; Park, J. K.; Kim, Y. M. (2020). "The first case report of neonatal bacterial meningitis caused by Streptococcus alactolyticus". Annals of Child Neurology. 28 (2): 69–71. doi:10.26815/acn.2019.00234. PMC 11061664. PMID 32310703.

External links

LPSN – Streptococcus alactolyticus

[Farrow1984-1] Farrow, J. A. E.; Kruze, J.; Phillips, B. A.; Bramley, A. J.; Collins, M. D. (December 1984). "Taxonomic studies on Streptococcus bovis and Streptococcus equinus: Description of Streptococcus alactolyticus sp. nov. and Streptococcus saccharolyticus sp. nov". Systematic and Applied Microbiology. 5 (4): 467–482. Bibcode:1984SyApM...5..467F. doi:10.1016/S0723-2020(84)80004-1.

[Rinkinen2004-2] Rinkinen, M.-L.; Koort, J.-M.; Ouwehand, A. C.; Westermarck, E.; Björkroth, K. J. (15 January 2004). "Streptococcus alactolyticus is the dominating culturable lactic acid bacterium species in canine jejunum and feces of four fistulated dogs". FEMS Microbiology Letters. 230 (1): 35–39. doi:10.1016/S0378-1097(03)00851-6. hdl:1975/521. PMID 14734163.

[Devriese1994-3] Devriese, L. A.; Hommez, J.; Pot, B.; Haesebrouck, F. (July 1994). "Identification and composition of the streptococcal and enterococcal flora of tonsils, intestines and faeces of pigs". Journal of Applied Bacteriology. 77 (1): 31–36. doi:10.1111/j.1365-2672.1994.tb03040.x. PMID 7928781.

[Jimenez2014-4] Jiménez, E.; Sánchez, B.; Farina, A.; Margolles, A.; Rodríguez, J. M. (2014). "Characterization of the bile and gall bladder microbiota of healthy pigs". MicrobiologyOpen. 3 (6): 937–949. doi:10.1002/mbo3.218. PMC 4263516. PMID 25336405.

[Devriese1991-5] Devriese, L. A.; Hommez, J.; Wijfels, R.; Haesebrouck, F. (July 1991). "Composition of the enterococcal and streptococcal intestinal flora of poultry". Journal of Applied Bacteriology. 71 (1): 46–50. doi:10.1111/j.1365-2672.1991.tb04480.x (inactive 20 July 2025). PMID 1910033.{{cite journal}}: CS1 maint: DOI inactive as of July 2025 (link)

[Yiu2011-6] Yiu, K. H. (2011). "Native-valve endocarditis due to Streptococcus alactolyticus: Case report and literature review". Clinical Microbiology and Infection. 17 (4): 630–632. doi:10.1111/j.1469-0691.2010.03258.x. PMID 20459438.

[Park2020-7] Park, S. J.; Yoon, L.; Park, J. K.; Kim, Y. M. (2020). "The first case report of neonatal bacterial meningitis caused by Streptococcus alactolyticus". Annals of Child Neurology. 28 (2): 69–71. doi:10.26815/acn.2019.00234. PMC 11061664. PMID 32310703.

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