Part:BBa_K2963032

racE- encoding racemase

This part contains the racE racemase gene, which was constructed using the tac (BBa_K864400) promoter, rbs (BBa_K2963006), racE gene (BBa_K2963004) and the T7 terminator (BBa_K2598024). This part was compared with the other part (BBa_K2963033) which contained another lac operator follwowing the tac promoter（BBa_K864400）.Simultaneously, the rest basic parts are the same. The racemase activity data and real-time PCR data were used to characterize the composite part. And we compared the different expression levels of racE gene of the two composite (BBa_K2963033 and BBa_K2963032）.

Usage and Biology

The racE gene is a type of racemase gene from Bacillus subtilis while in Bacillus licheniformis is named glr. According to previous reports, glr has two characters against L-glutamic acid, one is weak affinity and the other is strong catalytic properties.

Characterization

Figure 1 The expression level of the racemase gene racE at 8h,16h,24h decreased by 29.99%, 58.86% and 62.34% respectively. The results show that the expression intensity of racE was effectively reduced at each transcriptional stage by the tandem of two lacOs compared to one lacO.

Figure 2 we tested the enzyme activity of the racemase in cells. The result was the same as the above and the enzyme activity was different.

打算阿迪斯阿萨