User:BalboaalvarezM

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A Microbial Biorealm page on the genus BalboaalvarezM

Classification

Higher order taxa

Domain(Bacteria); Phylum(Firmicutes); Class(Bacilli); Order(Bacillales); Family(Staphylococcaceae); Genus(Staphylococcus)

Species

NCBI: Taxonomy

Species: Staphylococcus schleiferi

Subspecies: Staphylococcus schleiferi subsp. coagulans; Staphylococcus schleiferi subsp. schleiferi

Description and significance

The first description of the species Staphylococcus schleiferi was first done in April 1988. Contrarily the subspecies Staphylococcus schleiferi subsp. coagulans and Staphylococcus schleiferi subsp. schleiferi were identified many years later. Staphylococcus schleiferi subsp. coagulans is coagulase positive but instead Staphylococcus schleiferi subsp. schleiferi is coagulase negative (Kluytmans,2001).

Staphyloccous schleiferi is very similar in appearance than other species of staphylocci. It is particularly difficult to differentiate it from S. aureus because both species present a very similar morphology. It is actually believed that this is the reason why pathogenic activity by Staphylococcus schleiferi has been underreported, maybe some infections that were believed to be caused by S. aureus can actually be blamed on S. schleiferi (Kluytmans,2001).

It is important to study this bacterium because in the last few years disease caused by this pathogen has increased, so it must be better understood how this microorganism's metabolism works and how can it affect humans.

Genome structure

The complete genome sequence has not been coded for this bacterium, only portions of specific genes. It is known that it has a circular DNA. Studies of the gene sequence of some genes of Staphylococcus schleiferi have determined the expression of a Fibronectin-Binding Protein which increases the ability of the bacterium to add to other cells increasing its pathology (Peacock, 2000).

Cell structure and metabolism

Staphylococcus schleiferi is a cocciform, catalase-positive bacteria. It presents a cocci morphology and it forms part of the 36 species that conform the Staphylococcus genus.

The subspecies schleiferi has positive results for metabolic test which include catalase, clumping factor, nitrate reduction and acid production from D-glucose and D-mannose. Contrarily for the tests oxidase, coagulase, urease, lactose, maltose, sucrose the results observed for this subspecies are positive.

The subspecies coagulans has similar results for some of the tests but it can also have total different results for others. This subspecies has positive results for the coagulase, nuclease, nitrate reduction, phosphatase, urease, acid production from fructose and glucose tests. Instead for the clumping factor and oxidase test the results observed are negative. (McClung, 1974)

Ecology

When Staphylococcus shleiferi was first discovered nothing was known about the ecological niches of this microorganism. Nowadays it is known that its typical ecological niche is the skin and multiple mucosal surfaces. It is also believe that is part of the preaxilary human flora. In dogs, where it is most commonly observed it has been related to otitis due to its location in the auditory meatus of dogs.(Hernandez, 2001).

Pathology

Staphylococcus schleiferi is an opportunistic pathogen. Not much is known about the pathology of the coagulase-positive S. schleiferi subspecies. The other subspecies that is coagulase-negative has always been though as an apathogenic microorganism until more detailed research had been done more recently. It is believed that specific factors present in this bacterium make it more pathogenic that it was thought, this factors include bacterial polysaccharide components because they facilitate the attachment of these to foreign surfaces. They have also become more pathogenic with time because they have developed antibiotic resistance. Some of the infections that these bacteria can be associated with include bacteremia, catheter related infections, central nervous system shunt infections, endocarditis, urinary tract infection, surgical site infection, endophthalmitis. Staphylococcus schleiferi uses dogs as their most common host, but it has been discovered in the last few years that it can also be pathogenic to humans and other mammals. This Staphilococcus subspecies has been associated with recurrent pyoderma and otitis in dogs. Infection tends to come back even after antibiotic treatment. The virulence factors of these bacteria are the production of beta-hemolysin,lipase, and esterase.(Johannes, 2001)

Current Research and or Application to Biotechnology

There is research being done to scheme the differentiation between the S. schleiferi sups. coagulans from other coagulase-positive staphylococci (Igimi)

An increase number of endocarditis and infections after cardiac surgery cases in humans, possibly caused by Staphylococcus schleiferi have been detected. Therefore there are several projects to try to determine if it is really this particular bacterium who is causing the disease, how is it causing the disease and why had not been present in humans before.(Kluytmans)

Research is being done to be able to prove how resistant is this species of staphylococci to antibiotics. The research is also trying to determine to which specific antibiotics is the Staphylococcus schleiferi resistant to and why. (Bruno)

There are several projects working on trying to determine if pets could serve as reservoirs for spread of antibiotic-resistance in humans. Because Staphylococcus schleiferi is most commonly found in dogs and only here recently it has been detected in humans the concern for spread of disease has increased specially because a lot of people are in contact with dogs all the time but further studies are required. (Bruno)

References

Igimi, S., Takahashi, E., & Mitsuoka, T. (1990). Staphylococcus schleiferi subsp. coagulans subsp. nov., isolated from the external auditory meatus of dogs with external ear otitis. Int J Syst Bacteriol 40, 409-411.

Kluytmans Jan, Hans Berg, and Paul Steegh. "American Society for MicrobiologyJournal of Clinical Microbiology." Outbreak of Staphylococcus Schleiferi Wound Infections: Strain Characterization by Randomly Amplified Polymorphic DNA Analysis, PCR Ribotyping, Conventional Ribotyping, and Pulsed-Field Gel Electrophoresis. Journal of Clinical Microbiology, 1998. Web. 09 May 2012. <http://jcm.asm.org/content/36/8/2214.full.pdf html>.

Johannes Huebner, and Donald A. Goldmann. "COAGULASE-NEGATIVE STAPHYLOCOCCI: Role as Pathogens." - Annual Review of Medicine, 50(1):223. Annual Reviews, 2001. Web. 09 May 2012.

Peacock, S.J., G. Lina, and J. Etienne. "Staphylococcus Schleiferi Subsp. Schleiferi Expresses a Fibronectin-Binding Protein." Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin (2000). Web.

Hernandez, J. L., J. Calvo, R. Sota, and J. Aguero. "Clinical and Microbiological Characteristics of 28 Patients with Staphylococcus Schleiferi Infection." Uropean Journal of Clinical Microbiology & Infectious Diseases (2001): 153-58. Http://www.springerlink.com/content/5e7eauxjn00v7qfb/. Web.

McClung, N.M. (1974). Family VI: Nocardiaceae. In R. E. Buchanan & N. E. Gibbons (Eds.), Bergey's manual of determinative bacteriology (8th ed., pp 726-746). Baltimore, MD: Williams & Wilkins.

Bruno Penna, Renato Varges, and Rodrigo Martins. "In Vitro Antimicrobial Resistance of Staphylococci Isolated from Canine." PubMed Central. Canadian Veterinary Medical Association. Web.

Edited by student of Dr. Lynn M Bedard, DePauw University http://www.depauw.edu