Abstract:
:The global demand for food could double in another 40 y owing to growth in the population and food consumption per capita. To meet the world's future food and sustainability needs for biofuels and renewable materials, the production of starch-rich cereals and cellulose-rich bioenergy plants must grow substantially while minimizing agriculture's environmental footprint and conserving biodiversity. Here we demonstrate one-pot enzymatic conversion of pretreated biomass to starch through a nonnatural synthetic enzymatic pathway composed of endoglucanase, cellobiohydrolyase, cellobiose phosphorylase, and alpha-glucan phosphorylase originating from bacterial, fungal, and plant sources. A special polypeptide cap in potato alpha-glucan phosphorylase was essential to push a partially hydrolyzed intermediate of cellulose forward to the synthesis of amylose. Up to 30% of the anhydroglucose units in cellulose were converted to starch; the remaining cellulose was hydrolyzed to glucose suitable for ethanol production by yeast in the same bioreactor. Next-generation biorefineries based on simultaneous enzymatic biotransformation and microbial fermentation could address the food, biofuels, and environment trilemma.
journal_name
Proc Natl Acad Sci U S Aauthors
You C,Chen H,Myung S,Sathitsuksanoh N,Ma H,Zhang XZ,Li J,Zhang YHdoi
10.1073/pnas.1302420110subject
Has Abstractpub_date
2013-04-30 00:00:00pages
7182-7issue
18eissn
0027-8424issn
1091-6490pii
1302420110journal_volume
110pub_type
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