The rapid differentiation of Streptomyces isolates using Fourier transform infrared spectroscopy

Fifteen putative Streptomyces spp. isolated from soil were selected to be analysed using Fourier transform infrared (FT-IR) spectroscopy and 16S rRNA gene sequencing. Four colour groupings (groups 1-4) were obtained and described according to the colour of their substrate mycelia, aerial mycelia, spore mass and pigmentation. The dendrogram constructed using unsupervised cluster analysis of the FT-IR data was in good congruence with the four colour groups and the neighbour-joining phylogenetic tree for 16S rDNA sequencing. In particular, those isolates having 100% 16S rDNA similarities which are supposed to be from the same species can be separated from each other using FT-IR analysis. This high throughput method only takes 1-10 s to collect a FT-IR spectrum from each sample, and both 96- and 384-well microplates are available for automated analysis. FT-IR therefore presents itself as a rapid, whole-organism fingerprinting approach which can be used for preliminary differentiation of Streptomyces spp. at sub-species or strain level.