Beta-fructofuranosidase production by 2-deoxyglucose resistant mutants of aspergillus niger in submerged and solid-state fermentation.
Aspergillus niger produces extracellular beta-fructofuranosidase under submerged (SmF) and solid state fermentation (SSF) conditions. After UV mutagenesis of conidiospores of A. niger, 2-deoxyglucose (10 g/l) resistant mutants were isolated on Czapek's minimal medium containing glycerol as a carbon source and the mutants were examined for improved production of beta-fructofuranosidase in SmF and SSF conditions. One of such mutant DGRA-1 overproduced beta-fructofuranosidase in both SmF and SSF conditions. In SmF, the mutant DGRA-1 showed higher beta-fructofuranosidase productivity (110.8 U/l/hr) than the wild type (48.3 U/l/hr). While in SSF the same strain produced 322 U/l/hr of beta-fructofuranosidase, 2 times higher than that of wild type (154.2 U/l/hr). In SmF, both wild type and mutants produced relatively low level of beta-fructofuranosidase in medium containing sucrose with glucose than from the sucrose medium. However in SSF, the DGRA-1 mutant grown in sucrose and sucrose+ glucose did not show any difference with respect to beta-fructofuranosidase production. These results indicate that the catabolite repression of beta-fructofuranosidase synthesis is observed in SmF whereas in SSF such regulation was not prominent.
Ashokkumar
Balasubramaniem
B
Centre for Advanced Studies in Functional Genomics, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021, India.
Gunasekaran
Paramasamy
P
D001234:Aspergillus niger / Q000187:drug effects* / Q000201:enzymology; D003847:Deoxyglucose / Q000494:pharmacology*; D004351:Drug Resistance; D025141:Drug Resistance, Fungal; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000096:biosynthesis*; D007218:Industrial Microbiology; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D013395:Sucrose / Q000378:metabolism; D014466:Ultraviolet Rays; D043324:beta-Fructofuranosidase
D013395:Sucrose; D003847:Deoxyglucose; D006026:Glycoside Hydrolases; D043324:beta-Fructofuranosidase; D005947:Glucose