Genome shuffling improves thermotolerance and glutamic acid production of Corynebacteria glutamicum.
Genome shuffling was used to improve the thermotolerance of L: -glutamic acid-producing strain Corynebacteria glutamicum. Five strains with subtle improvements in high temperature tolerance and productivity were selected by ultraviolet irradiation and diethyl sulfate mutagenesis. An improved strain (F343) was obtained by three rounds of genome shuffling of the five strains as mentioned above. The cell density of F343 was four times higher than that of ancestor strains after 24 h of cultivation at 44°C, and importantly, the yield of L: -glutamic acid was increased by 1.8-times comparing with that of the ancestor strain at 38°C in a 5-L fermentor. With glucose supplement and two-stage pH control, the L: -glutamate acid concentration of F343 reached 119 g/L after fermentation for 30 h. The genetic diversity between F343 and its ancestors was also evaluated by amplified fragment length polymorphism analysis. Results suggest that the phenotypes for both thermotolerance and L: -glutamic acid production in F343 were evolved.
The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People's Republic of China.
Pu
P
Zheng
Miao
M
Liu
Xiao-de
XD
Liu
Qiao-Yan
QY
Du
Ye
Y
Ni
Zhi-Hao
ZH
Sun
D058491:Bacterial Load; D048230:Corynebacterium glutamicum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects*; D003470:Culture Media / Q000737:chemistry; D032621:DNA Shuffling; D004269:DNA, Bacterial / Q000235:genetics; D005285:Fermentation; D014644:Genetic Variation; D016680:Genome, Bacterial; D005947:Glucose / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D016296:Mutagenesis; D012150:Polymorphism, Restriction Fragment Length; D013463:Sulfuric Acid Esters / Q000378:metabolism; D014466:Ultraviolet Rays
D003470:Culture Media; D004269:DNA, Bacterial; D013463:Sulfuric Acid Esters; D018698:Glutamic Acid; D005947:Glucose; C011612:diethyl sulfate