Direct Liquid-Culture Screening for Evaluating the Production of Heterologous Proteins Using an Auxotrophic Mutant of Aspergillus Oryzae

Author(s):  
Satoru Shinkawa ◽  
Shigenobu Mitsuzawa

2004 ◽  
Vol 98 (3) ◽  
pp. 200-206 ◽  
Author(s):  
Masakazu Morita ◽  
Hiroko Shimamura ◽  
Natsuko Ishida ◽  
Koreyoshi Imamura ◽  
Takaharu Sakiyama ◽  
...  


2019 ◽  
Author(s):  
Ken Miyazawa ◽  
Akira Yoshimi ◽  
Motoaki Sano ◽  
Fuka Tabata ◽  
Asumi Sugahara ◽  
...  

AbstractFilamentous fungi generally form aggregated hyphal pellets in liquid culture. We previously reported that α-1,3-glucan-deficient mutants of Aspergillus nidulans did not form hyphal pellets and their hyphae were fully dispersed, and we suggested that α-1,3-glucan functions in hyphal aggregation. Yet, Aspergillus oryzae α-1,3-glucan-deficient (AGΔ) mutants still form small pellets; therefore, we hypothesized that another factor responsible for forming hyphal pellets remains in these mutants. Here, we identified an extracellular matrix polysaccharide galactosaminogalactan (GAG) as such a factor. To produce a double mutant of A. oryzae (AG-GAGΔ), we disrupted the genes required for GAG biosynthesis in an AGΔ mutant. Hyphae of the double mutant were fully dispersed in liquid culture, suggesting that GAG is involved in hyphal aggregation in A. oryzae. Addition of partially purified GAG fraction to the hyphae of the AG-GAGΔ strain resulted in formation of mycelial pellets. Acetylation of the amino group in galactosamine of GAG weakened GAG aggregation, suggesting that hydrogen bond formation by this group is important for aggregation. Genome sequences suggest that α-1,3-glucan, GAG, or both are present in many filamentous fungi and thus may function in hyphal aggregation in these fungi. We also demonstrated that production of a recombinant polyesterase, CutL1, was higher in the AG-GAGΔ strain than in the wild-type and AGΔ strains. Thus, controlling hyphal aggregation factors of filamentous fungi may increase productivity in the fermentation industry.ImportanceProduction using filamentous fungi is an important part of the fermentation industry, but hyphal aggregation in these fungi in liquid culture limits productivity compared with that of yeast or bacterial cells. We found that galactosaminogalactan and α-1,3-glucan both function in hyphal aggregation in Aspergillus oryzae, and that the hyphae of a double mutant deficient in both polysaccharides become fully dispersed in liquid culture. We also revealed the relative contribution of α-1,3-glucan and galactosaminogalactan to hyphal aggregation. Recombinant protein production was higher in the double mutant than in the wild-type strain. Our research provides a potential technical innovation for the fermentation industry that uses filamentous fungi, as regulation of the growth characteristics of A. oryzae in liquid culture may increase productivity.



1998 ◽  
Vol 85 (5) ◽  
pp. 488-494 ◽  
Author(s):  
Yasushi Wakisaka ◽  
Takayuki Segawa ◽  
Koreyoshi Imamura ◽  
Takaharu Sakiyama ◽  
Kazuhiro Nakanishi


1995 ◽  
Vol 80 (1) ◽  
pp. 41-45 ◽  
Author(s):  
Akinori Ogawa ◽  
Yasushi Wakisaka ◽  
Takaaki Tanaka ◽  
Takaharu Sakiyama ◽  
Kazuhiro Nakanishi


2006 ◽  
Vol 102 (5) ◽  
pp. 470-473 ◽  
Author(s):  
Bin Feng ◽  
Masakazu Morita ◽  
Hiroyuki Imanaka ◽  
Koreyoshi Imamura ◽  
Kazuhiro Nakanishi




1995 ◽  
Vol 80 (1) ◽  
pp. 35-40 ◽  
Author(s):  
Akinori Ogawa ◽  
Akinori Yasuhara ◽  
Takaaki Tanaka ◽  
Takaharu Sakiyama ◽  
Kazuhiro Nakanishi


2019 ◽  
Vol 10 ◽  
Author(s):  
Ken Miyazawa ◽  
Akira Yoshimi ◽  
Motoaki Sano ◽  
Fuka Tabata ◽  
Asumi Sugahara ◽  
...  




Sign in / Sign up

Export Citation Format

Share Document