Streptococcus zooepidemicus

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A Microbial Biorealm page on the genus Streptococcus zooepidemicus

Classification

Higher order taxa

Bacteria; Firmicutes; Bascilli; Lactobacillales; Streptococcaceae; Streptococcus

Species

NCBI: Taxonomy

Streptococcus equi

Subspecies

zooepidemicus

Other names

“Animal pyogenes, type A” [Edwards 1934]
“Streptococcus pyogene animalis” [Seelemann 1942]
“Streptococcus equi subsp. zooepidemicus” [Farrow and Collins 1985]

Type Strains

ATCC 43079
DSM 20727
NCDO 1358

Description and significance

Streptococcus zooepidemicus is one of the two subspecies of Streptococcus equi; it is suggested to be the species from which subspecies equi has been derived (5). Subspecies zooepidemicus is a normal bacterial flora in horses. It is isolated from wound infections of horses, and it has been isolated from other mammals such as cows, rabbits, and swine (3). In some cases, subspecies zooepidemicus is also isolated from humans through throat swabs (4). It occasionally causes human infection that can be traced back to contact with horses or consumption of unpasteurized dairy products (4).

Like other streptococci, Streptococcus zooepidemicus is a non-motile, non-sporulating, encapsulated, gram-positive, catalse-negative, and coccoid bacterium. It is a beta hemolytic streptococcus that produces hyaluronic acid but not streptolysin O and occurs in pairs or long chains (2). It is also lactose positive and is capable of fermenting sorbitol but not trehalose (3, 28).

Genome structure

Although the shotgun sequencing is complete with an available database of reads, the genome project of Streptococcus zooepidemicus is still in progress. At present, the genome size of this microorganism is about 2.3 Mb with a G+C content of approximately 41%, and 33,640 reads totaling 23.629Mb covering theoretically 99.99% of the genome (14). The similarity between the DNA of the two subspecies, zooepidemicus and equi, is over 92%. However, their biological behaviors in horses differ significantly. Subspecies zooepidemicus is a commensal of equine nasopharynx and external genitalia and causes infections in various areas, while subspecies equi is a contributing agent that causes strangles (3, 18). In addition, S. zooepidemicus has Szp proteins that may have an antiphagocytic role similar to the M proteins in group A streptococci (GAS) in the case of causing human infection. The Szp proteins not only share structural similarities with the M proteins but also stimulate opsonic antibodies just like the M proteins do (13).

Cell structure and metabolism

Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.

Ecology

Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.

Pathology

How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

Application to Biotechnology

Does this organism produce any useful compounds or enzymes? What are they and how are they used?

Current Research

Enter summaries of the most recent research here--at least three required

References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

Edited by Jenny Chong, student of Rachel Larsen