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Dickeya and Pectobacterium species represent an important group of broad-host-range phytopathogens responsible for blackleg and soft rot diseases on numerous plants including many economically important plants. Although these species are commonly detected using cultural, serological, and molecular methods, these methods are sometimes insufficient to classify the bacteria correctly. On that account, this study was undertaken to investigate the feasibility of three individual analytical techniques, capillary zone electrophoresis (CZE), capillary isoelectric focusing (CIEF), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), for reliable classification of Dickeya and Pectobacterium species. Forty-three strains, representing different Dickeya and Pectobacterium species, namely Dickeya dianthicola, Dickeya dadantii, Dickeya dieffenbachiae, Dickeya chrysanthemi, Dickeya zeae, Dickeya paradisiaca, Dickeya solani, Pectobacterium carotovorum, and Pectobacterium atrosepticum, were selected for this purpose. Furthermore, the selected bacteria included one strain which could not be classified using traditional microbiological methods. Characterization of the bacteria was based on different pI values (CIEF), migration velocities (CZE), or specific mass fingerprints (MALDI-TOF MS) of intact cells. All the examined strains, including the undetermined bacterium, were characterized and classified correctly into respective species. MALDI-TOF MS provided the most reliable results in this respect.

The methicillin-resistant Staphylococcus aureus causes difficult-to-treat healthcare-associated infections in humans. For fast and effective selection of an appropriate antibiotic therapy, it is essential to have rapid and reliable methods for differentiation of methicillin-resistant S. aureus from less dangerous methicillin-sensitive S. aureus. There have been many methods for the identification of methicillin-resistant S. aureus described but none has been accepted as an international standard. The most commonly used techniques such as phenotyping and genotyping have a few disadvantages, for instance, these techniques are not reproducible and stable. In addition, they are time-consuming, expensive, and they are not capable to distinguish all S. aureus strains. In this study, the methicillin-resistant and methicillin-sensitive S. aureus isolates obtained from patients were extracted in hot water. The released proteins were characterised by sodium dodecyl sulphate polyacrylamide gel electrophoresis and gel isoelectric focusing. These two methods were able to differentiate among tested bacterial strains. The proposed methods are time saving, they are applicable in standard biochemical laboratories, and they do not require any expensive equipment.

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