Navigation Links
Bright lights: Mystery of glowing antibody solved by Scripps research scientists
Date:2/28/2008

Now, a group of Scripps Research scientists have shown that EP2-19G2, one of a panel of fluorescent monoclonal antibodies that were first reported in 2000, produces its distinctive bright blue glow through a rare and highly complex recombination of electrical charge.

This charge recombination involves an electron holethe gap left by the electron as it is transferred from one molecule to the other.

The new study was published in the February 29, 2008 edition (Volume 319, Number 5867) of the journal Science.

Our study describes in detail the rare and rather surprising mechanism that creates this exceptionally bright and long-lasting fluorescent antibody, said Richard Lerner, president of The Scripps Research Institute, Lita Annenberg Hazen Professor of Immunochemistry, and member of the Skaggs Institute for Chemical Biology at Scripps Research. These findings could have wide application in the development of novel and more broadly applicable biosensors.

Biosensors, which relay biological reactions such as ligand binding and antibody-antigen actions into detectable signals, have a variety of uses, from signaling the presence of pathogens and toxins to monitoring blood glucose levels for diabetic patients.

When the monoclonal antibody EP2-19G2 is combined with stilbene, a hydrocarbon commonly used in making dyes, it emits an intense blue light after exposure to ultraviolet light. While other antibody-stilbene complexes have also shown the ability to produce purple, blue-purple, and blue fluorescence after UV exposure, their fluorescent effect has been relatively weak and short lived.

The luminescence produced by the EP2-19G2-stilbene complex lasts more than 400 times longer than that of stilbene on its own, said Erik Debler, the first author of the new study and a former graduate student of Professor Ian Wilsons laboratory at Scripps Research. This is probably the longest luminescence lifetime that has ever been observed for stilbene and was totally unexpected, especially since stilbene is basically the E. coli of photochemistry, as it is extremely well characterized and understood.

The fact that the EP2-19G2-stilbene complex emits a bright luminescence was first described in a Scripps Research study published in the October 13, 2000 edition (Volume 290, Number 5490) of the journal Science. The underlying mechanism had remained unknown until now.

A Perfect Match, A Perfect Storm

When EP2-19G2 binds stilbene, the antibody itself coordinates the joining or stacking of stilbene with a deeply buried tryptophan residue at the active site. In other fluorescent antibodies, such a stacking interaction does not exist. After exposure to UV, electron transfer between stilbene and tryptophan occurs deep within the 19G2 protein matrix.

Kim Janda, who is Ely R. Callaway, Jr. Chair in Chemistry, member of The Skaggs Institute for Chemical Biology, and director of the Worm Institute for Research and Medicine at Scripps Research, led the initial research into EP2-19G2 and was part of the new study. He described the importance of the combination this way: This may be a perfect molecular storm. When the tryptophan residue and stilbene are matched in EP2-19G2, this perfect alignment creates a different luminescence pathway than is seen in other related antibodies.

Unlike in other complexes, this antibody reacts with stilbene in the excited state. Antibody EP2-19G2 is deeply penetrated by the stilbene molecule and the special constellation of the stilbene-tryptophan pairing sets this antibody apart from other antibody-stilbene complexes, where binding merely enhances stilbene fluorescence by inhibiting photoisomerization, the dominant nonradiative decay pathway of stilbene in solution.

In fact, the unusual binding mode of stilbene in EP2-19GE2 is enabled by a non-canonical interface of the variable heavy and light chains of the antibody.

This light-generating mechanism has rarely been observed in other luminescent proteins found in nature, Debler said. The neat thing about this system is that it acts like a molecular light switch. Neither stilbene nor the antibody themselves are notably fluorescent, but, when these two molecules combine, they yield an incredibly intense blue light.

It is the special photophysical behaviorthe extreme brightness coupled with the switch-like characterthat makes the EP2-19G2 antibody attractive as a potential biosensor and as a model for the development of other equally potent types of luminescent antibody-chromophore complexes.


'/>"/>

Contact: Mika Benedyk
mbenedyk@scripps.edu
858-784-2052
Scripps Research Institute
Source:Eurekalert

Related biology news :

1. Researchers set new record for brightness of quantum dots
2. Has the mystery of the Antarctic ice sheet been solved?
3. UCLA researchers solve decade-old mystery
4. Ancient mystery solved
5. ASU professor helps solve mystery of glassy water
6. 480-million-year-old fossil sheds light on 150-year-old paleontological mystery
7. Time-sharing tropical birds key to evolutionary mystery
8. Cassini on the trail of a runaway mystery
9. Magnetic snakes control fluids, gravity-defying droplets, and solving a dragonfly mystery
10. Men shed light on the mystery of human longevity, study finds
11. Folate mystery finally solved
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/22/2016)... India , March 22, 2016 /PRNewswire/ ... market research report "Electronic Sensors Market for Consumer ... Proximity, & Others), Application (Communication & IT, ... Geography - Global Forecast to 2022", published ... industry is expected to reach USD 26.76 ...
(Date:3/18/2016)... --> --> Competitive Landscape ... Vehicles, Physical infrastructure and Perimeter Surveillance & Detection Systems ... market and the continuing migration crisis in the ... has led visiongain to publish this unique report, which is ... & security companies in the border security market and ...
(Date:3/15/2016)... Yissum Research Development Company of the ... the Hebrew University, announced today the formation of ... various human biological indicators. Neteera Technologies has completed its ... investors. ... electromagnetic emissions from sweat ducts, enables reliable and speedy ...
Breaking Biology News(10 mins):
(Date:4/28/2016)... (PRWEB) , ... April 28, 2016 , ... ... and ongoing support for Connecticut's innovative, growing companies, today announced the launch of ... and financial technology (fintech) companies. , “VentureClash looks to attract the ...
(Date:4/27/2016)... ... April 27, 2016 , ... Shimadzu Scientific Instruments ... Spring 2016 Marijuana Business Conference and Expo. Shimadzu’s high-performance instruments enable laboratories to ... more. Expo attendees can stop by booth 1021 to learn how Shimadzu’s instruments ...
(Date:4/27/2016)... Virgin Islands (PRWEB) , ... April 27, 2016 ... ... Company Ltd. (d/b/a Biohaven) is pleased to announce the appointment of John Tilton as ... was an Executive Director and one of the founding commercial leaders responsible for ...
(Date:4/27/2016)... ... ... Global Stem Cells Group and the University of Santiago Biotechnology Lab have ... for potential stem cell protocol management for 2016 – 2020. , In 2015, ... establish a working agenda and foster initiatives to promote stem cell research and development ...
Breaking Biology Technology: