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Stachybotrys chartarum and Stachybotrys chlorohalonata are two closely related species. Unambiguous identification of these two species is a challenging task if relying solely on morphological criteria and therefore smarter and less labor-intensive approaches are needed. Here we show that even such closely related species of fungi as S. chartarum and S. chlorohalonata are unequivocally discriminated by their highly reproducible MALDI-TOF-MS fingerprints (matrix assisted laser desorption/ionization time-of-flight mass spectrometry fingerprints). We examined 19 Stachybotrys and one Aspergillus isolate by MALDI-TOF-MS. All but one isolate produced melanin containing conidia on malt extract agar. Mass spectra were obtained in good quality from the analysis of hyaline and darkly pigmented conidia by circumventing the property of melanin which causes signal suppression. MALDI-TOF fingerprint analysis clearly discriminated not only the two morphologically similar species S. chartarum and S. chlorohalonata from each other but separated them precisely from Stachybotrys bisbyi and Aspergillus versicolor isolates. Furthermore, even S. chartarum chemotypes A and S could be differentiated into two distinct groups by their MALDI-TOF fingerprints. The chemotypes of S. chartarum isolates were identified by trichodiene synthase 5 ( tri5 ) sequences prior to mass spectra analysis. Additionally, species identities of all isolates were verified by their 18S rRNA and tri5 gene sequences. [ABSTRACT FROM AUTHOR]

Abstract: Water miscible metal working fluids (MWF) are prone to contamination by bacteria and fungi. In the present work it was investigated which components of a model MWF emulsion were most readily degraded by microorganisms and which are relatively resistant to biodegradation. The microbial community colonising an MWF emulsion, during its lifetime under in-use conditions was analysed up to species level. Shifts in the composition of microbial community were related to chemical changes in the MWF emulsion over time. [Copyright &y& Elsevier]

The guts of termites feature suitable conditions for methane oxidizing bacteria (MOB) with their permanent production of CH 4 and constant supply of O 2 via tracheae. In this study, we have isolated MOB from the gut contents of the termites Incisitermes marginipennis , Mastotermes darwiniensis , and Neotermes castaneus for the first time. The existence of MOB was indicated by detecting pmoA , the gene for the particulate methane monooxygenase, in the DNA of gut contents. Fluorescence in situ hybridization and quantitative real-time polymerase chain reaction supported those findings. The MOB cell titer was determined to be 10 2 –10 3 per gut. Analyses of the 16S rDNA from isolates indicated close similarity to the genus Methylocystis . After various physiological tests and fingerprinting methods, no exact match to a known species was obtained, indicating the isolation of new MOB species. However, MALDI-TOF MS analyses revealed a close relationship to Methylocystis bryophila and Methylocystis parvus . [ABSTRACT FROM AUTHOR]