Genetic Typing:

There are various methods that can be used to perform genetic typing of Xylella fastidiosa isolates.  The Xylella Project utilizes a detailed scheme, the Multilocus Sequence Typing (MLST) system, to identify different strains of Xylella.  Other methods (such as the 16s ribosomal RNA and the spacer between the 16S and 23S ribosomal RNA) are less effective.

MLST characterizes isolates of bacteria on the basis of sequence variation, using internal fragments of about 500bp from each of seven housekeeping genes.  The different sequences at each locus are assigned different allele numbers, and each isolate is defined by the alleles at the seven loci (the allelic profile).  Each unique allelic profile defines a sequence type (ST), which is a convenient and un-ambiguous descriptor for distinguishing genetically different isolates.

If you think you have an infected plant and would like a complimentary analysis, visit our Sending Samples page.  We will contact you with instructions and we will make arrangements for sample shipment.

The technical details of how to apply this MLST method in your own lab can be found at the MLST website and data base: www.pubmlst.org/xfastidiosa/ or see Yuan et al. (2010).