气候变化领域集成服务门户(CCPortal): Crossing the Thauer limit: Rewiring cyanobacterial metabolism to maximize fermentative H2 production

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DOI	10.1039/c8ee03606c
	Crossing the Thauer limit: Rewiring cyanobacterial metabolism to maximize fermentative H2 production
	Kumaraswamy K.G.; Krishnan A.; Ananyev G.; Zhang S.; Bryant D.A.; Dismukes G.C.
发表日期	2019
ISSN	17545692
起始页码	1035
结束页码	1045
卷号	12 期号:3
英文摘要	Many cyanobacteria power metabolism during dark anaerobic conditions by the catabolism of glycogen which creates adenylate energy (ATP) and NAD(P)H. The latter can be reoxidized by a reversible NiFe-hydrogenase functioning as a terminal oxidoreductase generating H2 as byproduct. Theoretically, one glucose molecule can yield up to 12 molecules of H2, although this never happens in vivo. The thermodynamic preference is for glucose catabolism via the Embden-Meyerhof-Parnas (EMP) pathway (henceforth, glycolysis) which restricts the pathway yield below 4 mole H2 per mole glucose (so-called Thauer limit). An alternate route that is not used is the oxidative pentose phosphate shunt (OPP), which theoretically can yield 3-fold more NAD(P)H than glycolysis. Herein, we engineer the cyanobacterium Synechococcus sp. PCC 7002 to redirect glycogen catabolic flux through OPP by deleting the gap1 gene for glyceraldehyde-3-phosphate dehydrogenase (GAPDH-1) and stack this with a knock-out mutation of NADH-consuming lactate dehydrogenase (ldhA). The resulting Δgap1ΔldhA double mutant when combined with the elimination of H2 uptake by continuous electrochemical removal of H2 was able to produce 681 μmol H2 per g DW per day, equivalent to 6.4 mole H2 per mole glucose, well beyond the Thauer limit. This achieves the highest in vivo autofermentative H2 production yield of any bacterium, equivalent to 80% of the theoretical maximum of 8 H2 per glucose via OPP, using only photoautotrophically generated glycogen as precursor with full retention of cellular viability. These findings demonstrate the plasticity of central carbon metabolism and the significant potential of metabolic engineering for redirecting carbohydrate catabolism towards hydrogen production in cyanobacteria. © 2019 The Royal Society of Chemistry.
英文关键词	Glucose; Metabolic engineering; Metabolism; Molecules; Pathology; Physiology; Anaerobic conditions; Cellular viability; Central carbon metabolisms; Electrochemical removal; Glucose molecules; Glyceraldehyde-3-phosphate dehydrogenase; Lactate dehydrogenase; Pentose phosphates; Hydrogen production; anoxic conditions; carbohydrate; catabolism; cyanobacterium; enzyme activity; fermentation; glucose; hydrogen; metabolism; physiological response; thermodynamics; Bacteria (microorganisms); Cyanobacteria; Synechococcus elongatus PCC 6301; Synechococcus sp. PCC 7002
语种	英语
来源期刊	Energy & Environmental Science
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/189969
作者单位	Waksman Institute, Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, United States; Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, United States; Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, United States; Department of Biochemistry, University of Alberta, Edmonton, AL T6G2RE, Canada; Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, 500 Technology Square NE47-140, Cambridge, MA 02139, United States
推荐引用方式 GB/T 7714	Kumaraswamy K.G.,Krishnan A.,Ananyev G.,et al. Crossing the Thauer limit: Rewiring cyanobacterial metabolism to maximize fermentative H2 production[J],2019,12(3).
APA	Kumaraswamy K.G.,Krishnan A.,Ananyev G.,Zhang S.,Bryant D.A.,&Dismukes G.C..(2019).Crossing the Thauer limit: Rewiring cyanobacterial metabolism to maximize fermentative H2 production.Energy & Environmental Science,12(3).
MLA	Kumaraswamy K.G.,et al."Crossing the Thauer limit: Rewiring cyanobacterial metabolism to maximize fermentative H2 production".Energy & Environmental Science 12.3(2019).