天津科技大学学报2016，Vol.31Issue(3)：25-30,6.DOI:10.13364/j.issn.1672-6510.20150159
敲除iclR基因对大肠杆菌发酵L-色氨酸的影响
Effects of Knockout of GeneiclRonL-tryptophan Fermentation inEscherichia coli
摘要
Abstract
Escherichia coli TRTH ΔiclRwas constructed via knockout oficlR,the key gene of the glyoxylate shunt in E.coliTRTH through Red recombination to study the effects oficlR knockout onE.coliTRTHL-tryptophan accumula-tion.The results of shake flask fermentation indicated that the yield ofL-tryptophan and the titer ofL-tryptophan from glu-cose ofE.coli TRTH ΔiclRreached(6.52±0.46)g/L and 13.17%,,which were 21.86%, and 22.85%, higher than those ob-tained fromE.coli TRTH,respectively;6.82,g/L of acetic acid accumulated in the culture ofE.coli TRTH ΔiclR,which was 37.63%, lower than that of the control strain.In the fermentation of 30,L fermenter,the titer and yield ofL-tryptophan of E.coli TRTH ΔiclR were(13.01±1.05)g/L and 6.51%,,which were 60.34%, and 68.27%, lower than those of the control, respectively;18.21,g/L acetic acid,33.42%, times higher than that of the control,accumulated in the broth.In conclusion,in shake flask fermentation assays,the metabolic flux of the recombined strain was beneficial forL-tryptophan accumulation although the biomass was lower thanE.coli TRTH.On the contrary,enhancement of glyoxylate shunt resulted in the short-age of energy supply and higher acetic acid accumulation,which can lead to lower biomass andL-tryptophan titer in 30,L fermentation.关键词
L-色氨酸/大肠杆菌/乙醛酸循环/iclR/发酵Key words
L-tryptophan/Escherichia coli/glyoxylate shunt/iclR/fermentation分类
生物科学引用本文复制引用
陈胜杰,刘辉,谢希贤,徐庆阳,陈宁..敲除iclR基因对大肠杆菌发酵L-色氨酸的影响[J].天津科技大学学报,2016,31(3):25-30,6.基金项目
国家高技术研究发展计划资助项目(2012AA022102，2012AA02A703)；天津市科技支撑计划重点资助项目(14ZCZDSY00015) （2012AA022102，2012AA02A703）
