Difference between revisions of "Part:BBa K3733006"
| Line 3: | Line 3: | ||
<partinfo>BBa_K3733006 short</partinfo> | <partinfo>BBa_K3733006 short</partinfo> | ||
| − | <p>Gesomin synthase from <i>Streptomyces coelicolor</i> A3(2) (<b>ScGS</b>) is a single 726-amino acid protein which | + | <p>Gesomin synthase from <i>Streptomyces coelicolor</i> A3(2) (<b>ScGS</b>) is a single 726-amino acid protein which catalyze the Mg<sup>2+</sup> dependent conversion of farnesyl diphosphate to a mixture including geosmin. ScGS is a bifunctional enzyme in which the N-terminal domain catalyze the cyclization of FPP to form germacradienol, while the C-terminal domain then convert this sesquiterpenoid product to <b>geosmin</b>.</p> |
===Usage and Biology=== | ===Usage and Biology=== | ||
| − | |||
<p>The ScGS is a bifunctional sesquiterpene cyclase, with the presence of Mg<sup>2+</sup>, the N-terminal half of this protein catalyzes the ionization and cyclization of farnesyl diphosphate to form germacradienol and inorganic pyrophosphate(PP<sub>i</sub>). Then the C-terminal domain, highly homologous with the former, catalyzes the protonation, cyclization, and fragmentation of germacradienol to form geosmin and acetone.</p> | <p>The ScGS is a bifunctional sesquiterpene cyclase, with the presence of Mg<sup>2+</sup>, the N-terminal half of this protein catalyzes the ionization and cyclization of farnesyl diphosphate to form germacradienol and inorganic pyrophosphate(PP<sub>i</sub>). Then the C-terminal domain, highly homologous with the former, catalyzes the protonation, cyclization, and fragmentation of germacradienol to form geosmin and acetone.</p> | ||
===Sequence and Features=== | ===Sequence and Features=== | ||
| − | <partinfo> | + | <partinfo>BBa_K3733006 SequenceAndFeatures</partinfo> |
| − | + | ||
===Functional Parameters=== | ===Functional Parameters=== | ||
| − | |||
<p>To obtain ScGS, pET-28a(+)-ScGS(with His-tag) was transferred into <i>E.coli</i> BL21(DE3), and the cells were inoculated in 25 mL cultures of LB medium with 10 μg/mL kanamycin. These cultures were grown at 37℃ with 250 rpm shaking until the OD<sub>600</sub> reached 0.5-0.8, then 0.3 mM isopropyl <i>β</i>-D-1-thiogalactopyranoside(IPTG) were added, following by an overnight cultivation at 16℃ with 250 rpm shaking to induce protein expression. The washed and harvested cells were resuspended with a Binding Buffer, and then the cells were lysed by ultrasonication. Purification was performed according to the protocol of Ni-NTA Sefinose<sup>TM</sup> Resin (Sangon Biotech, Shanghai, China). As it shows in the following figure(<b>figure 1.</b>), the existence of ScGS in our chasis was clearly proved by SDS-PAGE analysis.</p> | <p>To obtain ScGS, pET-28a(+)-ScGS(with His-tag) was transferred into <i>E.coli</i> BL21(DE3), and the cells were inoculated in 25 mL cultures of LB medium with 10 μg/mL kanamycin. These cultures were grown at 37℃ with 250 rpm shaking until the OD<sub>600</sub> reached 0.5-0.8, then 0.3 mM isopropyl <i>β</i>-D-1-thiogalactopyranoside(IPTG) were added, following by an overnight cultivation at 16℃ with 250 rpm shaking to induce protein expression. The washed and harvested cells were resuspended with a Binding Buffer, and then the cells were lysed by ultrasonication. Purification was performed according to the protocol of Ni-NTA Sefinose<sup>TM</sup> Resin (Sangon Biotech, Shanghai, China). As it shows in the following figure(<b>figure 1.</b>), the existence of ScGS in our chasis was clearly proved by SDS-PAGE analysis.</p> | ||
| Line 46: | Line 43: | ||
| − | |||
| − | < | + | ===References=== |
| − | [1] Harris G G, Lombardi P M, Pemberton T A, et al. Structural Studies of Geosmin Synthase, a Bifunctional Sesquiterpene Synthase with αα Domain Architecture That Catalyzes a Unique Cyclization–Fragmentation Reaction Sequence[J]. Biochemistry, 2015, 54(48): 7142-7155. | + | <p>[1] Harris G G, Lombardi P M, Pemberton T A, et al. Structural Studies of Geosmin Synthase, a Bifunctional Sesquiterpene Synthase with αα Domain Architecture That Catalyzes a Unique Cyclization–Fragmentation Reaction Sequence[J]. Biochemistry, 2015, 54(48): 7142-7155.</p> |
| − | </ | + | |
<P>[2] Xie Y, He J, Huang J, et al. Determination of 2-methylisoborneol and geosmin produced by Streptomyces sp. and Anabaena PCC7120[J]. Journal of agricultural and food chemistry, 2007, 55(17): 6823-6828.</P> | <P>[2] Xie Y, He J, Huang J, et al. Determination of 2-methylisoborneol and geosmin produced by Streptomyces sp. and Anabaena PCC7120[J]. Journal of agricultural and food chemistry, 2007, 55(17): 6823-6828.</P> | ||
Revision as of 16:04, 18 October 2021
ScGS: Streptomyces coelicolor geosmin synthase
Gesomin synthase from Streptomyces coelicolor A3(2) (ScGS) is a single 726-amino acid protein which catalyze the Mg2+ dependent conversion of farnesyl diphosphate to a mixture including geosmin. ScGS is a bifunctional enzyme in which the N-terminal domain catalyze the cyclization of FPP to form germacradienol, while the C-terminal domain then convert this sesquiterpenoid product to geosmin.
Usage and Biology
The ScGS is a bifunctional sesquiterpene cyclase, with the presence of Mg2+, the N-terminal half of this protein catalyzes the ionization and cyclization of farnesyl diphosphate to form germacradienol and inorganic pyrophosphate(PPi). Then the C-terminal domain, highly homologous with the former, catalyzes the protonation, cyclization, and fragmentation of germacradienol to form geosmin and acetone.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000COMPATIBLE WITH RFC[1000]
Functional Parameters
To obtain ScGS, pET-28a(+)-ScGS(with His-tag) was transferred into E.coli BL21(DE3), and the cells were inoculated in 25 mL cultures of LB medium with 10 μg/mL kanamycin. These cultures were grown at 37℃ with 250 rpm shaking until the OD600 reached 0.5-0.8, then 0.3 mM isopropyl β-D-1-thiogalactopyranoside(IPTG) were added, following by an overnight cultivation at 16℃ with 250 rpm shaking to induce protein expression. The washed and harvested cells were resuspended with a Binding Buffer, and then the cells were lysed by ultrasonication. Purification was performed according to the protocol of Ni-NTA SefinoseTM Resin (Sangon Biotech, Shanghai, China). As it shows in the following figure(figure 1.), the existence of ScGS in our chasis was clearly proved by SDS-PAGE analysis.
In order to identify the synthesis of geosmin, engineered bacteria in TB medium containing 5% glycerol were first induced ScGS expression with 0.7mM IPTG when OD600 reached about 0.7, following by an overnight culture at 18℃ and continuing cultivation for next 72h at 25℃. From this way we could smell a strong and unusual odor from the culture comparing to the control.
For further demonstration, we prepared the sample via headspace liguid-phase microextraction(HS-LPME) and a gas chromatography-mass spectrometry(GC-MS) test was conducted. The results given by GC-MS fairly shows the existence of geosmin in our culture(figure 2.), thus prove the feasibility of the part.
===References===
[1] Harris G G, Lombardi P M, Pemberton T A, et al. Structural Studies of Geosmin Synthase, a Bifunctional Sesquiterpene Synthase with αα Domain Architecture That Catalyzes a Unique Cyclization–Fragmentation Reaction Sequence[J]. Biochemistry, 2015, 54(48): 7142-7155.
[2] Xie Y, He J, Huang J, et al. Determination of 2-methylisoborneol and geosmin produced by Streptomyces sp. and Anabaena PCC7120[J]. Journal of agricultural and food chemistry, 2007, 55(17): 6823-6828.