(GTG)5 microsatellite regions in citrinin-producing Penicillium.

Morphological and cultural characteristics, as well as biochemical properties, are the main criteria used in fungal taxonomy and in the standard description of fungi species. Sometimes, however, this criterion is difficult to apply due to fungal phenotypic variations. This is particularly true in the genus Penicillium. The aims of this work were to determine (GTG)5 microsatellite sequence in potentially citrinin-producing Penicillium strains and to investigate if this sequence could be useful to characterize such fungi. Penicillium citrinum Thom and Penicillium chrysogenum Thom were isolated from different foods. The identification of the isolates at species level was carried out according to classical taxonomy. The production of citrinin was determined by thin layer chromatography. This study proved that microsatellite regions exist as short repeated sequences in all tested strains. The patterns were very similar for all P. citrinum isolates and it was possible to group them in function of the quantity of citrinin produced. Yet, not similar clusters were obtained when P. chrysogenum isolates were analyzed.