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Updated: Aug 18, 2026

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Aseptic Laboratory Techniques: Plating Methods
Published on: May 11, 2012
Pseudodiffuse-type growth of a Staphylococcus aureus strain in serum-soft agar
Journal of Clinical Microbiology
|July 1, 1985
Abstract:
Strain MC31 of Staphylococcus aureus showed diffuse-type growth in regular serum-soft agar (SSA) (pH 7.2), but in alkaline SSA (pH 8.4) the type of growth was compact. The organisms were of extra low virulence in the mouse and were unencapsulated. Based on three properties, the growth type of the S. aureus strains in SSA was designated as pseudodiffuse type.
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