Double mutation of Saccharomyces cerevisiae for enhanced β-D-fructofuranosidase fructohydrolase productivity and application of growth kinetics for parametric significance analysis

Revista de microbiologia

Ali, Sikander¹  Aslam, Aafia² 

[1] GC University Lahore, Pakistan;Kinnaird College for Women (KCW), Lahore, Pakistan

关键词: Saccharomyces cerevisiae;    β;    -d-Fructofuranosidase fructohydrolase;    Kinetics and thermodynamics;    Entropy and enthalpy.;   

DOI  :  10.1016/j.bjm.2015.11.024

学科分类：农业科学（综合）

来源: Sociedade Brasileira de Microbiologia / Brazilian Society for Microbiology

【 摘 要 】

The kinetics of an extracellular β-D-fructofuranosidase fructohydrolase production by Saccharomyces cerevisiae in a chemically defined medium, i.e., sucrose peptone agar yeast extract at pH 6, was investigated. The wild-type was treated with a chemical mutagen, methyl methane sulfonate. Among the six mutants isolated, methyl methane sulfonate-V was found to be a better enzyme producing strain (52 ± 2.4a U/mL). The maximum production (74 ± 3.1a U/mL) was accomplished after at 48 h (68 ± 2.7a mg/mL protein). The mutants were stabilized at low levels of 5-fluoro-cytocine and the viable ones were further processed for optimization of cultural conditions and nutritional requirements. The sucrose concentration, incubation period and pH were optimized to be 30 g/L, 28 °C, and 6.5, respectively. The methyl methane sulfonate-V exhibited an improvement of over 10 folds in enzyme production when 5 g/L ammonium sulfate was used as a nitrogen source. Thin layer chromatography and high-performance liquid chromatography analysis illustrated the optimal enzyme activity supported by the higher rate of hydrolysis of sucrose into monosaccharides, particularly α-D-glucose and β-D-fructose. The values for Qp (2 ± 0.12c U/mL/h) and Yp/s (4 ± 1.24b U/g) of the mutant were considerably increased in comparison with other yeast strains (both isolates and viable mutants). The mutant could be exploited for enzyme production over a wider temperature range (26–34 °C), with significantly high enzyme activity (LSD 0.048, HS) at the optimal temperature.

【 授权许可】

CC BY-NC