ABSTRACT
Enhanced Pr1 and Pr2 activities were observed in entomopathogenic fungi Beauveria bassiana (UB9) and Metarhizium anisopliae (UM4) supplemented with casein. Highest activity was observed at 72 hours of incubation when compared to minimal medium (MM) and colloidal chitin amended media. The extra cellular proteases (Pr1 and Pr2) thus isolated were purified through dialysis and their activities were found to be increased by two-fold. Pr1 and Pr2 were subjected to SDS - PAGE analysis and activity gel electrophoresis. The molecular weight of protease produced by Beauveria bassiana (UB9) is 19 KD and that of Metarhizium anisopliae (UM4) is 21 KD.
ABSTRACT
Protease hyper producing recombinant strains were produced by intergeneric protoplast fusion of entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae. β-glucuronidase and KCl were used as lysing enzyme and osmotic stabilizer. Along with inter-generic fusion, intra-strain and inter-strain fusions were also carried out using polyethylene glycol (PEG) as fusogen. When the fused protoplasts were regenerated on Czapekdox agar medium, they exhibited fast mycelial growth and abundant sporulation when compared to non-fusants. Pr1 and Pr2 specific activities were found to be increased by two- fold in recombinant strains than the nonfusants and the parental strains.
ABSTRACT
Twenty nine pathotypes of Beauveria bassiana (Bals.) Vuill and one of Beauveria brongniartii (Sacc.) petch were characterized according to virulence towards second instar larval stage of Spodoptera litura and isozyme variations. Biological differences were found among the isolates. LT50 values ranged from 4.2 to 9.6 days based on which the isolates were characterized as virulent and less virulent. Electrophoretic polymorphisms of esterase and acid phosphatase were performed to differentiate the isolates. Cluster analysis revealed a demarcation among the virulent and less virulent isolates of B. bassiana from that of B. brongniartii species.