| Autor: |
Sukwong P; Department of Biotechnology, Pukyong National University, Busan, 48513, South Korea., Sunwoo IY; Department of Biotechnology, Pukyong National University, Busan, 48513, South Korea., Jeong DY; Department of Food Science and Biotechnology, Kyungpook National University, Daegu, 37224, South Korea., Kim SR; Department of Food Science and Biotechnology, Kyungpook National University, Daegu, 37224, South Korea., Jeong GT; Department of Biotechnology, Pukyong National University, Busan, 48513, South Korea., Kim SK; Department of Biotechnology, Pukyong National University, Busan, 48513, South Korea. skkim@pknu.ac.kr. |
| Abstrakt: |
A total monosaccharide concentration of 47.0 g/L from 12% (w/v) Gracilaria verrucosa was obtained by hyper thermal acid hydrolysis with 0.2 M HCl at 140°C for 15 min and enzymatic saccharification with CTec2. To improve galactose utilization, we overexpressed two genes, SNR84 and PGM2, in a Saccharomyces cerevisiae CEN-PK2 using CRISPR/Cas-9. The overexpression of both SNR84 and PGM2 improved galactose utilization and ethanol production compared to the overexpression of each gene alone. The overexpression of both SNR84 and PGM2 and of PGM2 and SNR84 singly in S. cerevisiae CEN-PK2 Cas9 produced 20.0, 18.5, and 16.5 g/L ethanol with ethanol yield (Y EtOH ) values of 0.43, 0.39, and 0.35, respectively. However, S. cerevisiae CEN-PK2 adapted to high concentration of galactose consumed galactose completely and produced 22.0 g/L ethanol at a Y EtOH value of 0.47. The overexpression of both SNR84 and PGM2 increased the transcriptional levels of GAL and regulatory genes; however, the transcriptional levels of these genes were lower than those in S. cerevisiae adapted to high galactose concentrations. |
Full text from SpringerLink