On-line green fluorescent protein sensor with LED excitation

✍ Scribed by Lisa Randers-Eichhorn; C. Renee Albano; Jeffrey Sipior; William E. Bentley; Govind Rao

• Book ID: 101242803
• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 140 KB
• Volume: 55
• Category: Article
• ISSN: 0006-3592
• DOI: 10.1002/(sici)1097-0290(19970920)55:6<921::aid-bit9>3.0.co;2-i

✦ Synopsis

We present an intensity based sensor designed for on-line monitoring of green fluorescent protein, a revolutionary marker of protein expression. The device consisted of a blue light emitting diode as the excitation source. A band pass excitation filter cut off light longer than 490 nm. The light was directed into a bifurcated optical fiber bundle with the common end inserted into a stainless steel housing equipped with a quartz window. The fiber bundle and stainless steel housing are steam sterilizable. The emission radiation was collected through a long wave pass filter to reject the excitation light shorter than 505 nm and was detected by a photomultiplier tube. The signal was amplified and sent to a computer for recording time course data. The sensor was tested in an Escherichia coli fermentation of JM105 transformed with pBAD-GFP. The on-line signal was compared to off-line fluorescence spectrophotometer measurements. The on-line profile closely followed the off-line. Western blot data showed that with a time shift, the sensor was able to both continuously and quantitatively monitor expression of green fluorescent protein on-line in real time.