Development of a base stacking hybridization-based microarray method for rapid identification of clinical isolates.

A base stacking hybridization-based microarray method was developed for rapid identification of clinical isolates within 2 h. The oligonucleotide probe sequences for species or genus-level identification were targeted against ribosomal RNA. Isolates were lysed and directly hybridized to the microarray-bound capture probes without conventional DNA or RNA isolation and prior polymerase chain reaction amplification. Five bacterial species encountered frequently in the clinical setting, Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae, and one genus Enterococcus, could be discriminated by the microarray-based assay. Identification by this method matched biochemical identification for 150 of 152 clinical strains. This base-stacking hybridization microarray offers a simple, fast (</=2 h), and accurate identification of bacterial cultures and is a potential tool for routine clinical diagnosis.