Genetic Diversity in Hyper Glucose Oxidase Producing Aspergillus niger UAF Mutants by using Molecular Markers.

Glucose oxidase (ß-D glucose: oxygen-oxidoreductase, GOD) is of prime importance in food and health industries for the production of gluconic acid, maintaining flavor and color stability and quantification of glucose in blood and urine etc. Aspergillus niger is one of the key producers of GOD. We report the genetic diversity assessment of A. niger University of Agriculture Faisalabad (UAF) wild type strain and its seventeen mutants. The mutants developed via four mutagens viz., UV rays, gamma rays, ethidium bromide and MNNG for the hyper production of Glucose Oxidase. Molecular typing methods have been used for the detection of polymorphism within the members of any fungal genera as well as species. However, this is the pioneering attempt which focuses on detection of polymorphism in A. niger UAF parent strain and its mutants using RAPD and SSRs. Out of 26 RAPD primers used in the study, 12 produced polymorphic banding pattern amplifying 125 bands with an average of 10.41 fragments per primer. The most diverse mutants were UV-180-A and UV-180-B. All the mutants and a wild type strain were divided into six different groups except the mutant EMS-F which appeared unclustered. For SSR analysis, six different microsatellites were applied (AN01-06), which amplified 2-3 alleles in the mutants ranging from 100-450 bp size. The results revealed the existence of high genetic variability among the mutant strains and a wild type strain. [ABSTRACT FROM AUTHOR]