TY - JOUR
T1 - A genetic and metabolic approach to redirection of biochemical pathways of Clostridium butyricum for enhancing hydrogen production
AU - Cai, Guiqin
AU - Jin, Bo
AU - Monis, Paul
AU - Saint, Chris
PY - 2013/1
Y1 - 2013/1
N2 - Clostridium butyricum, a well known H2 producing bacterium, produces lactate, butyrate, acetate, ethanol, and CO2 as its main by-products from glucose. The conversion of pyruvate to lactate, butyrate and ethanol involves oxidation of NADH. It was hypothesized that the NADH could be increased if the formation of these by-products could be eliminated, resulting in enhancing H2 yield. Herein, this study aimed to establish a genetic and metabolic approach for enhancing H2 yield via redirection of metabolic pathways of a C. butyricum strain. The ethanol formation pathway was blocked by disruption of aad (encoding aldehyde-alcohol dehydrogenase) using a ClosTron plasmid. Although elimination of ethanol formation alone did not increase hydrogen production, the resulting aad-deficient mutant showed approximately 20% enhanced performance in hydrogen production with the addition of sodium acetate. This work demonstrated the possibility of improving hydrogen yield by eliminating the unfavorable by-products ethanol and lactate.
AB - Clostridium butyricum, a well known H2 producing bacterium, produces lactate, butyrate, acetate, ethanol, and CO2 as its main by-products from glucose. The conversion of pyruvate to lactate, butyrate and ethanol involves oxidation of NADH. It was hypothesized that the NADH could be increased if the formation of these by-products could be eliminated, resulting in enhancing H2 yield. Herein, this study aimed to establish a genetic and metabolic approach for enhancing H2 yield via redirection of metabolic pathways of a C. butyricum strain. The ethanol formation pathway was blocked by disruption of aad (encoding aldehyde-alcohol dehydrogenase) using a ClosTron plasmid. Although elimination of ethanol formation alone did not increase hydrogen production, the resulting aad-deficient mutant showed approximately 20% enhanced performance in hydrogen production with the addition of sodium acetate. This work demonstrated the possibility of improving hydrogen yield by eliminating the unfavorable by-products ethanol and lactate.
KW - aad disruption
KW - Clostridium butyricum
KW - Ethanol formation pathway
KW - Fermentative hydrogen production
KW - NaAc addition
UR - http://www.scopus.com/inward/record.url?scp=84869886828&partnerID=8YFLogxK
U2 - 10.1002/bit.24596
DO - 10.1002/bit.24596
M3 - Letter
SN - 0006-3592
VL - 110
SP - 338
EP - 342
JO - Biotechnology and Bioengineering
JF - Biotechnology and Bioengineering
IS - 1
ER -