Miksch Gerhard, Ryu Stella, Risse Joe Max, Flaschel Erwin
Forschungszentrum für Medizintechnik und Biotechnologie, 99947, Bad Langensalza, Germany.
Appl Microbiol Biotechnol. 2008 Nov;81(2):319-26. doi: 10.1007/s00253-008-1673-1. Epub 2008 Sep 16.
Aiming to increase production of recombinant streptavidin in Escherichia coli, the effect of different leader sequences, different promoter strengths of the bacteriocin release protein (kil), host strain and medium composition on the expression and secretion into the medium was investigated. Expression vectors containing an expression or secretion unit were constructed with different combinations of leader sequence for the streptavidin gene and promoters for the kil gene and streptavidin gene. Results showed that a high-level extracellular production of streptavidin could be accomplished with E. coli BL21(DE3) by using the leader sequence of the phoA gene, a strong stationary-phase promoter for the kil gene and supplementation of the medium by glycine. Using a stationary-phase promoter for the expression of streptavidin had a negative effect.
为了提高重组链霉亲和素在大肠杆菌中的产量，研究了不同前导序列、细菌素释放蛋白（kil）的不同启动子强度、宿主菌株和培养基组成对其表达及分泌到培养基中的影响。构建了含有表达或分泌单元的表达载体，这些载体采用了链霉亲和素基因前导序列与kil基因和链霉亲和素基因启动子的不同组合。结果表明，通过使用phoA基因的前导序列、kil基因的强稳定期启动子以及在培养基中添加甘氨酸，大肠杆菌BL21(DE3)能够实现链霉亲和素的高水平胞外表达。使用稳定期启动子来表达链霉亲和素具有负面影响。
