Differenzierung und Charakterisierung von humanpathogenen Hefen (Candida albicans, Exophiala dermatitidis) und tierpathogenen Algen (Prototheca spp.) mittels Fourier‐Transform‐Infrarot‐Spektroskopie (FT‐IR) im Vergleich zu konventionellen Methoden

Zusammenfassung. Die Fourier‐Transform‐Infrarot‐Spektroskopie (FT‐IR) erwies sich als eine geeignete und effiziente Methode für diagnostische und epidemiologische Bestimmungen bei den Hefen Candida albicans, Exophicla dermalitidis und chlorophyllosen Algen der Gattung Prototheca aufgrund eindeutig abgrenzbarer IR‐Spektren stammspezifischer Merkmale. FT‐IR führt schnell und ökonomisch zu reproduzierbaren Ergebnissen. Unterschiedliche Genera, Spezies und Subspezies bzw. differierende Stämme können anhand spektraler Unterschiede kompletter Zellen (IR‐Fingerprints) in eindeutige Cluster und Subcluster eingeordnet werden. Die FT‐IR‐Analysen bei Candida albicans‐Isolaten (n = 150) von 22 Risikoneugeborenen einer Intensivstation ergaben, daß 86% der Kinder mit mehreren (2–4) unterschiedlichen Stämmen in Mundhöhle und Faeces besiedelt waren. Stationäre Kreuzinfektionen ließien sich eindeutig nachweisen. Summary. Due to the Fourier‐Transform Infrared Spectroscop)‐ (FT‐IR) of strain specific traits demonstrated t o be a suitable and efficient method for diagnostic and epidemiological determinations for the yeasts Candida albicans, Exophiala dermatitidis and the chlorophylless algae of the genus Prototheca. FT‐IR leads in a rapid and economical way to reproducible results according to the spectral differences of intact cells (IR‐fingerprints). Different genera, species and sub‐species respective13 different strains can be recognized and grouped into different clusters arid subclusters. The FT‐IK analysis of Cundida albicans isolates (n = 150) of 22 nekvborns‐at‐risk of an intensive care unit sholvcd, that 86% of the children were colonised with seiwal (2–4) different strains in the oral cavities and faeces. Stationary cross‐infections could definitely be determined. Erofihiala dumatitidis isolates (n = 31), mostly isolatcd repetitixdy within a period of 3 years from sputa of patients suffering from cystic fibrosis could be characterized and grouped patient‐specificically over the total sampling period. Of 6 from 8 patients (75 %) their indi{idual strains remain the same and could be tracked over thr three years. Cross‐infections during the stationary treatment could be clearly identified by FT‐IR. Thr Protorheca isolate (n = 43) from live‐stock and farm environment showed clear distinguishable clustrrs differrntiating the species 2 wickerhamii, P Zopji and Pstagnoru. In addition, the biotypes ofP'opji could bc distinguished, especially the subclusters of variants I1 and 111. It could be demonstrated, that FT‐IR is suitable for the routine identification and differentiation of yeasts and algae. However. in spite of the gain of knowledge by using F7‐IR for the characterization of microorganisms, the conventional phenotyping and/or genetic analysis of cast or algae strains cannot be replaced completely For a final taxonomic classification a combination of conventional methods on FT‐IR together with more sophisticated molecular genetic procedures is necessary.