MALDI-TOF mass spectrometry - a quicker tool to identify dampess related actinomycetes?

摘要

Thousands of microbial samples are collected yearly from Finnish buildings suspected of dampness problems, either from building materials, surfaces or indoor air. The present laboratory techniques rely mostly on the cultivation method, and on the identification of colonies with light microscopy. The interpretation of results are based on the microbial concentrations and the composition of microbiota. The list of microbial 'signature taxa' of moisture damage in Finland consists of some 25 fungal taxa, and actinomycetes-type bacteria. The group of Actinomycetes is large and polyphyletic, and there is a clear need to determine more accurately, which subtaxa arereally connected to dampness and/or potential health problems and which are not. Matrix-assisted laser desorption-ionization time - of - flight mass spectrometry (MALDI-TOF MS) is a proteomic based technique for identification microbes. This technique is widely in use in the identification of pathogenic microbes in hospital settings. Our project aims at testing the applicability of MALDI-TOF in identification of environmental microbes, sampled from buildings with dampness problems. In the first phase of the project we have developed an extraction procedure for aerobic Actinomycete isolates and started to build a non-clinical MALDI-TOF library for these environmental Actinobacteria. The potential use of MALDI-TOF in indoor investigations would have several assets. From cultivated samples, idenfication procedure is fast, only some minutes, simple and cost-effective. The technique brings new possibilities to species level identification, previously needed DNA sequencing or chemotaxonomical methods.