Expression of an Acidothermus cellulolyticus endoglucanase in transgenic rice seeds.
The thermostable endo-1,4-β-glucanase (E1) from Acidothermus cellulolyticus, is a useful enzyme for commercial hydrolysis of cellulose into glucose. A codon-optimized synthetic gene encoding this enzyme was transformed into rice (Oryza sativa L. ssp. japonica) under the control of the rice seed storage protein Gt1 promoter. The transgenic line C19 was identified as the one with the highest endoglucanase activity among the total of 36 independent transgenic lines obtained. The cellulase activity in the C19 seeds was estimated at about 830U/g of dried seeds using CMC as substrate. The enzymes produced in the seeds had an optimum pH of 5.0 and optimum temperature of 80°C, which is similar to the enzymes produced by the native bacterium host. This study demonstrates that the transgenic rice seeds could be used as a bioreactor for production of enzymes for cellulosic biomass conversion.
State Key Laboratory of Rice Biology and Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China.
Qing
Q
Zhang
Wei
W
Zhang
Chaoyang
C
Lin
Xiaoli
X
Xu
Zhicheng
Z
Shen
D000192:Actinomycetales / Q000201:enzymology*; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification; D015139:Blotting, Southern; D002480:Cellulase / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification; D012639:Seeds / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D011994:Recombinant Proteins; D002480:Cellulase