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Identification of PST 10 bacterial isolate with ?-hemolysis characteristic isolated from pig's tonsil

  • Hamong Suharsono ,
  • I Wayan Suardana ,
  • Rizki Kusuma Putri ,


Background: Pig's tonsil is one of the entry points and habitat of commensal microbes and pathogenic bacteria, both Gram-positive and Gram-negative bacteria. Recently, a human meningitis outbreak has reported at Sibang Kaja, Badung-Bali. The cause of this outbreak has been suspected due to the consumption of pig-derived foods. The outbreak was known to be caused by Gram-positive ?-hemolytic bacteria. Based on this fact, PST 10 bacterial isolate with similar characteristics to the outbreak caused interesting identification.

Method: PST 10 isolate was cultivated in a specific medium 5% defibrinated sheep blood agar plate. Subsequently, Gram staining, catalase, oxidase, salt tolerance (6% NaCl), and hemolysis test. This presumptive isolation was then conventionally identified by KIT API 20 STREP and molecularly using the 16S rRNA gene.

Results: PST 10 isolate was identified as Enterococcus faecium using KIT API 20 STREP. Furthermore, the 16S rRNA gene sequencing analysis shows that the isolate has 99.6% similarities with Enterococcus faecalis (MG543832). The isolate shares the same clade in the phylogenetic tree analysis with a 100% bootstrap value.

Conclusion: The high sensitivity in molecular identification mainly to distinguish close species using phenotypic approaches, PST 10 isolate was concluded as Enterococcus faecalis.


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How to Cite

Suharsono, H., Suardana, I. W., & Putri, R. K. (2022). Identification of PST 10 bacterial isolate with ?-hemolysis characteristic isolated from pig’s tonsil. Bali Medical Journal, 11(1), 56–60.




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Hamong Suharsono
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I Wayan Suardana
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Rizki Kusuma Putri
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