Medical Microbiology and Immunology

, Volume 174, Issue 3, pp 115–118 | Cite as

Assay of extracellular proteinases using a colorimetric collagen substrate for the differentiation ofSerratia in the tribe Klebsielleae

  • S. C. Edberg
  • M. K. Edberg


The gelatin test has been utilized for many years as a characteristic to separate the genusSerratia from other members of the tribe Klebsielleae. Gelatin is a large protein matrix that cannot diffuse into bacterial cells. Microbes that attack gelatin do so by producing extracellular proteinases. The measurement of gelatinase has suffered from the lack of a defineable endpoint and the inability to quantitate the enzyme. A method was developed utilizing an azodye-labelled collagen substrate that could measure the extracellular proteinase ofSerratia. The test was easy to perform, inexpensive, and potentially quantifiable. The azodye test corresponded completely with the gelatinase tests.


Collagen Gelatin Bacterial Cell Protein Matrix Large Protein 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • S. C. Edberg
    • 1
  • M. K. Edberg
    • 1
  1. 1.Department of Laboratory MedicineYale University School of MedicineNew HavenUSA

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