DIAGNOSTIC METHODS AND REAGENTS FOR DETECTION AND QUANTIFICATION OF RHODOCOCCUS EQUI BASED ON CHOE AND VAPA GENES

摘要

A two-stage assay for detecting Rhodococcus equi in a DMA containing sample, said method comprising in a first stage, detecting in said sample, the presence or absence of a nucleic acid which is characteristic of a first gene from Rhodococcus equi (eg. ChoE) , which is conserved in all strains of R. equi, and, if this is found to be present, subjecting the sample to a second stage in which the presence or absence of a nucleic acid which is characteristic of a second gene Rhodococcus equi (eg. VapA) which is specific to a specific host, is detected. The first nucleic acid is suitably quantitated to provide a useful means for determining the amounts of R. equi in the sample. ChoE is present as monocopy on the chromosome, in contrast to VapA which is present in variable gene copy number in different bacterial cells. Kits for use in the assay are also described and claimed.