Difference between revisions of "Part:BBa J45992:Experience"

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===Applications of BBa_J45992===
 
===Applications of BBa_J45992===
 
A stationary phase-dependent PoPS source.
 
A stationary phase-dependent PoPS source.
 
J45992 was characterized by measuring flourescence intensity of the in a plate reader.  The characterization device was <bbpart>BBa_J45995</bbpart>.  In figure A, the absorbance, which is proportional to cell density, is plotted against fluorescence, or roughly the number of GFP molecules present in the culture.  It is seen in the graph that J45995 (J45992.E0840) exhibits a much higher level of fluorescence during stationary phase (Absorbance>0.5, see figure B) than during exponential phase (yellow line).  Additionally, J45992 was attached to an inverter (<bbpart>BBa_Q04401</bbpart>) and the signal was effectively turned off at stationary phase (green line).
 
 
[[Image:BBa J45992-3characterization.png|left|thumb|600px|<font size=3>Figure A - J45992 chracterization (yellow), with signal inverted (green), with control constitutive promoter (grey), and with no fluorescent protein coding region (purple)</font>]][[Image:osmYgraph.jpg|left|thumb|600px|<font size=3>Figure B - Graph shows that cell reach stationary phase at absorbance ~0.5</font>]]
 
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===User Reviews===
 
===User Reviews===

Revision as of 00:04, 8 March 2008

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Please enter how you used this part and how it worked out.

Applications of BBa_J45992

A stationary phase-dependent PoPS source.

User Reviews

UNIQeba5db1c558bd86e-partinfo-00000000-QINU

•••••

Reshma Shetty

BBa_J45992, when used to regulate transcription of GFP in BBa_J45995 or banana odor enzyme generator in BBa_J45250, demonstrated the expected behavior. BBa_J45992 produced a low transcriptional signal in exponential phase and a high transcriptional signal in stationary phase.

UNIQeba5db1c558bd86e-partinfo-00000006-QINU

Characterization

Growth phase dependent transcriptional control devices
We successfully designed, constructed and tested transcriptional control devices for constitutive, stationary phase dependent and exponential phase dependent protein production (A-C). To test and verify function of our three transcriptional control devices, we assembled each control device with the GFP protein generator BBa_E0840 and monitored the fluorescence of E. coli cultures with each device over time. For each device, we plot the change in fluorescence per unit time (normalized GFP synthesis rate) versus the cell density (OD600nm) (D). The constitutive transcriptional control device produced a high GFP synthesis rate irrespective of cell density. The stationary phase transcriptional control device produced a low initial GFP synthesis rate which increased with culture cell density. The exponential phase transcriptional control device produced an initially high GFP synthesis rate which dropped off as cell density increased. Data shown are averages of triplicate measurements of cultures grown from three individual colonies of each device. Error bars are the standard deviation of the three individual cultures.