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CRISPR/CAS9을 이용하여 lipid elongation gene의 과발현을 통한 효모의 에탄올 발효능 개선

Enhancement of Ethanol Productivity with Saccharomyces cerevisiae by Overexpression of Lipid Elongation Gene Using CRISPR/CAS9

  • 김진아 (부경대학교 생물공학과) ;
  • 정귀택 (부경대학교 생물공학과)
  • Kim, JinA (Department of Biotechnology, Pukyong National University) ;
  • Jeong, Gwi-Taek (Department of Biotechnology, Pukyong National University)
  • 투고 : 2021.02.22
  • 심사 : 2021.03.24
  • 발행 : 2021.06.28

초록

본 연구에서는 CRISPR/CAS9을 이용하여 S. cerevisiae의 ACC1, ELO1, OLE1 유전자의 프로모터를 TEF1으로 교체하여 그 발현량을 증가시키고 그에 따른 에탄올에 대한 저항성과 생산량 변화를 확인하였다. 18% 에탄올이 함유된 YPD 배지에서 control을 제외하고 유전자 과발현을 일으킨 mutant 균주 모두가 24시간까지 viable하게 생존하는 것을 확인하였다. 에탄올 발효에서는 유전자 과발현 균주 모두가 에탄올 수율에서 ACC1 과발현 균주가 428.18 ± 0.29 mg/g, ELO1 과발현 균주는 416.15 ± 4.3 mg/g, OLE1 과발현 균주는 430.55 ± 6.00 mg/g에 도달하였으며, 이는 control의 수율인 400.26 ± 0.42 mg/g 보다 높은 수준에 도달하였다. 이 결과는 높은 농도의 에탄올에서 탄소 사슬이 긴 불포화지방산의 비율이 증가한다는 연구결과가 역 또한 성립한다는 것을 증명하였다. ELO1의 과발현은 elongation of fatty acid protein의 생산 증가를 불러 일으킨다. 또한 OLE1도 acylCoA desaturase 효소의 활성을 증대시킨다. TEF1이라는 strong promoter를 이용한 이번 실험에서 ELO1 과발현 균주가 OLE1 과발현 균주보다 S. cerevisiae의 에탄올 저해 감소와 발효에 긍정적인 영향을 미침을 확인하였다.

This study aimed to enhance ethanol productivity of Saccharomyces cerevisiae through genome editing using CRISPR/CAS9. To increase ethanol productivity, ACC1, ELO1, and OLE1 were overexpressed in S. cerevisiae using the CRISPR/CAS9 system. The strains overexpressing ACC1, ELO1, and OLE1 survived up to 24 h in YPD medium supplemented with 18% ethanol. Moreover, the ethanol yields in strains overexpressing ACC1 (428.18 mg ethanol/g glucose), ELO1 (416.15 mg ethanol/g glucose), and OLE1 (430.55 mg ethanol/g glucose) were higher than those in the control strains (400.26 mg ethanol/g glucose). In conclusion, the overexpression of these genes increased the viability of S. cerevisiae at high ethanol concentrations and the ethanol productivity without suppressing glucose consumption.

키워드

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