Acta Microbiologica 37. (1990)
4. szám - Vágvölgyi, Cs.–Brückner, B.–Frankó, A.: Size-Dependent Regeneration of Gibberella Protoplasts
4 Acta Microbiologica Hangar ica 37 (4), pp. 375—378 (1990) SIZE-DEPENDENT REGENERATION OF GIBBERELLA PROTOPLASTS Cs. Vágvölgyi, Bettina Brückner and A.Frankó Department of Microbiology, Attila József University, Szeged, Hungary, and Department of General Microbiology, Friedrich Schiller University, Jena, FRG (Received April 19, 1990) Regeneration ratios of protoplasts formed from the plant pathogenic Gibberella fujikuroi with a mixture of lytic enzymes were studied. The heterogeneous population of protoplasts was separated into groups differing in regeneration ratio. The frequency of regeneration was higher for large protoplasts containing an increased number of nuclei. The regeneration ratios of different fungal species display a great diversity [1]. H owever, even the reversion ratios of mutants from the same strain can differ [2]. These ratios always relate to the reversion of morphologically heterogeneous protoplast population. Within this population, there are differences in the metabolic abilities of the individual protoplasts [3]. Isaac et al. [4, 5] described a connection between the regeneration ability and the site of hyphal origin of Aspergillus nidulans protoplasts; those formed from a distal hyphal region regenerate better. Shawcross et al. [6] found that medium-sized A. nidulans protoplasts selected by filtration regenerate better than smaller or larger ones. Nycodenz, 5-(iV-2,3-dihydroxypropylacetamido)-2,4,6-triiodo-7V,IV’-bis(2,3-dihydroxypropyl) isophthalamide, is a nonionic density gradient medium that is very versatile in biological separations [7]. Because of its ability to form isoosmotic gradients, it has been successfully used for separations of osmotically susceptible particles such as organelles [8] or yeast protoplasts [9]. The aim of this study was to clarify the relationship between protoplast size, the number of nuclei and the regeneration capability (frequency) of Gibberella fujikuroi protoplasts. Csaba Vágvöi.gyi, András Frankó Department of Microbiology, Attila József University H-6071, Szeged, P.O.B. 428, Hungary Bettina Brückner Department of General Microbiology, Friedrich Schiller University Neugasse 24, Jena, D-O-6900, FRG Acta Microbiologica Ilungarica 37, 1900 Akadémiai Kiadó, Budapest