title: Protoplasts from Aspergillus nidulans.
abstract: A very effective lytic enzyme system for massive micro/macro-scale production of protoplasts from the filamentous fungus Aspergillus nidulans is described. A striking coincidence was observed between maximal lytic activity towards Aspergillus mycelium and the presece of both chitinase and alpha-(1 leads to 3)-glucanase activities. The release of protoplasts was greatly enhanced by preincubating the mycelium with 2-deoxy-D-glucose. Furthermore, protoplast formation was influenced by fungal age, culture conditions, pH of incubation and the osmotic stabilizer used. From 40 mg of fresh mycelium, grown for 14--16 h on 1% glucose in a low phosphate-citrate medium, preincubated with 2-deoxy-D-glucose for 45 min, and then incubated with the lytic enzyme mixture at pH 6.5 in the presence of 0.3--0.4 M (NH4) SO4, 2.5 x 10(8) stable protoplasts were produced within 3 h of incubation at 30 degrees C. Comparable results were obtained with 40--50 g of mycelium. At low osmotic stabilizer concentrations a peculiar type of regeneration was observed in the presence of the lytic enzyme system; within 12 h of incubation aberrant hyphal structure emerged from the large vacuolated protoplasts.
mesh_terms: D001233:Aspergillus nidulans / Q000166:cytology* / Q000201:enzymology; D002688:Chitinases / Q000378:metabolism; D003470:Culture Media; D003847:Deoxyglucose / Q000494:pharmacology; D005936:Glucans; D006867:Hydrolases / Q000378:metabolism; D009618:Nocardiaceae / Q000201:enzymology; D011523:Protoplasts
chemical_list: D003470:Culture Media; D005936:Glucans; D003847:Deoxyglucose; D006867:Hydrolases; D002688:Chitinases