The Growth Precipitation Test As a Diagnostic Method for Differentiation of Mycoplasma and Acholeplasma Species

Abstract

The purpose of this paper is to evaluate the growth precipitation (GP) test for routine identification. The test was performed as described by Heitmann & Kirchhoff (1978) which is a modification of the method of Krogsgaard-Jensen (1972). On the basis of examination of 82 strains, using indirect immunofluorescence (IMF) and growth inhibition (GI) as well as GP tests it is concluded that the GP test seems to be very useful for species identification in the genus Acholeplasma, as this method displayed fewer cross-reactions between species than the other 2 tests. When applied to the genus Mycoplasma, however, the GP test is not species-specific, due to cross reactions observed within the group of arginine positive and within the group of glucose and scrum digestion positive species. In the genus Mycoplasma the method can only be used as a screening tool, and final identification is in general based on growth inhibition and immunofluorescence.

Sammendrag

Formålet med dette arbejde er at vurdere vækstprsecipitationsteknikken (GP) specielt med henblik p rutineidentifikation ai stammer af slægterne Myco- og Acholeplasma. Testen blev udført son beskrevet af Heitmann & Kirchhoff (1978), en modifikation af den oprindelige metode udformet af Krogsgaard-Jensen (1972). P basis af undersøgelse af 82 stammer, under anvendelse af indirekte immunofluorescens, væksthæmning og GP konkluderes, at sidstnævnte er meget anvendelig til speciesidentifikation indenfor slægten Acholeplasma, idet vækstpræcipitation var mere artsspecifik end de 2 andre tests. Derimod fandtes metoden ikke at være anvendelig til artsdifferentiering indenfor slægten Mycoplasma, idet der hyppigt optrådte krydsreaktioner både indenfor argininspaltende arter og i den gruppe af glukosespaltende og serumdigestion-positive arter, som bl. a. rummer de stammer, der er rsag til ondartet lungesyge hos køer, henholdsvis geder.