The addition of Mn(II) to an early stationary-phase Deinococcus radiodurans RI culture could induce a new round of cell division (MnCD effect). The addition of Mn(II) could also stimulate the utilization of glucose and fructose in this bacterium. Class II fructose-1,6-bisphosphate aldolase (FBA) is an Mn-dependent key enzyme in pentose phosphate pathway. Therefore, in this research, we focused on the studies of the fba gene. Base on the gene sequence, FBA protein was composed of 306 amino acids, (M.W., 32.4 kDa¡F pI, 5.4). The expected PCR product size of the fba gene is 9.3 kbp. We had amplified the fba gene by using both Taq DNA polymerase and pfu turbo DNA polymerase. The sequence of the pfu turbo DNA polymerase products showed a higher homology with the fba gene than those of using Taq DNA polymerase. These amplified fba gene was cloned into three expression vectors, pGEX-4T-2, pQE30, and pET28a, and then further expressed in E. coli BL21(DE3)RIL and JM109. The recombinant GST-FBA protein could be overproduced in pTDA2/BL21(DE3)RIL. However, the expressed insoluble protein accumulated as inclusion bodies in the cells and exhibited no enzyme activity. After partial purification, and processing by thrombin protease cleavage, urea treatment, and the addition of Mn(II), this enzyme still showed no activity. The recombinant pEDA2/BL21(DE3)RIL strain cells grew in 18¢J and induced by 0.1mM IPTG could produced a soluble form His-Thrombin-T7-FBA protein which performed a 50X higher activities than those cells grew in 30¢J. This result indicated that decreasing the indicatioin temperature could improve the protein solubility and activity.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0922103-154503 |
| Date | 22 September 2003 |
| Creators | Chen, Kuan-Wen |
| Contributors | Jong-Kang Liu, Chi-Hsin Hsu, Chan-Shing Lin |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0922103-154503 |
| Rights | off_campus_withheld, Copyright information available at source archive |
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