합성 일산화탄소:개미산 산화환원효소를 포함하고 있는 초고온성 고세균을 이용한 CO가스의 개미산 생전환

Abstract

Electron transfer pathways in biology are central to a wide range of essential metabolic pathways, from photosynthesis to fermentation, and crucial for the reduction of inorganic chemicals into biologically functional molecules as well. Ferredoxin-dependent metabolic engineering of electron transfer circuit has been developed to enhance the redox efficiency in the region of synthetic biology, such as hydrogen production, and reduction of flavoproteins or NAD(P)+. Herein, we show that a bioconversion of CO gas to formate (CO + H2O &#61664 HCOO- + H+, DG`o=-16.5 kJ/mol) via a synthetic carbon monoxide:formate oxidoreductase (CFOR) that is designed as an enzyme complex for direct electron transfer between non-interacting carbon monoxide dehydrogenase (CODH) and formate dehydrogenase (FDH) from T. onnurineus NA1. To develop a CO-formate bioconversion mutant strains, the synthetic CFORs were constructed and introduced into the genome of T. onnurineus NA1 under the control of a strong promoter. As a result, the mutant strain, supplemented with CO, produced 18 mM of formate both cell growth and resting cell experiment. During a pH-stat batch culture with a purging of 100% CO in the bioreactor, the volumetric formate productivity and the specific formate productivity were determined as 400 mmol L-1 d-1 and 528 mmol g-dcw-1 d-1, respectively, after 9 h of fermentation. Homologous expressed CFOR was purified using metal affinredoxin-dependent metabolic engineering of electron transfer circuit has been developed to enhance the redox efficiency in the region of synthetic biology, such as hydrogen production, and reduction of flavoproteins or NAD(P)+. Herein, we show that a bioconversion of CO gas to formate (CO + H2O &#61664 HCOO- + H+, DG`o=-16.5 kJ/mol) via a synthetic carbon monoxide:formate oxidoreductase (CFOR) that is designed as an enzyme complex for direct electron transfer between non-interacting carbon monoxide dehydrogenase (CODH) and formate dehydrogenase (FDH) from T. onnurineus NA1. To develop a CO-formate bioconversion mutant strains, the synthetic CFORs were constructed and introduced into the genome of T. onnurineus NA1 under the control of a strong promoter. As a result, the mutant strain, supplemented with CO, produced 18 mM of formate both cell growth and resting cell experiment. During a pH-stat batch culture with a purging of 100% CO in the bioreactor, the volumetric formate productivity and the specific formate productivity were determined as 400 mmol L-1 d-1 and 528 mmol g-dcw-1 d-1, respectively, after 9 h of fermentation. Homologous expressed CFOR was purified using metal affin