Details

Autor(en) / Beteiligte

• Balážová, Tereza
• Makovcová, Jitka
• Šedo, Ondrej
• Slaný, Michal
• Faldyna, Martin
• Zdráhal, Zbyněk

Titel

The influence of culture conditions on the identification of Mycobacterium species by MALDI-TOF MS profiling

Ist Teil von

• FEMS microbiology letters, 2014-04, Vol.353 (1), p.77-84

Ort / Verlag

Oxford, UK: Blackwell Publishing Ltd

Erscheinungsjahr

2014

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• Abstract Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) represents a simple reliable approach for rapid bacterial identification based on specific peptide/protein fingerprints. However, cell-wall characteristics of mycobacterial species, and their well known stability, complicate MALDI-TOF MS profiling analysis. In this study, we tested two recently published protocols for inactivation and disruption of mycobacteria, and we also examined the influence of different culture conditions (four culture media and five cultivation times) on mass spectral quality and the discriminatory power of the method. We found a significant influence of sample pretreatment method and culture medium on species identification and differentiation for a total of 10 strains belonging to Mycobacterium phlei and Mycobacterium smegmatis. Optimum culture conditions yielding the highest identification success rate against the BioTyper database (Bruker Daltonics) and permitting the possibility of automatic acquisition of mass spectra were found to be distinct for the two mycobacterial species examined. Similarly, individual changes in growth conditions had diverse effects on the two species. For these reasons, thorough control over cultivation conditions should always be employed to maximize the performance and discriminatory power of MALDI-TOF MS profiling, and cultivation conditions must be optimized separately for individual groups of mycobacterial species/strains. Sample preparation and growth conditions have species-specific influence on MALDI-TOF MS profiling outputs of mycobacteria and thus should be optimized individually to obtain accurate identification.