Related Experiment Video
Updated: Jun 14, 2026

Synthesis and Calibration of Phosphorescent Nanoprobes for Oxygen Imaging in Biological Systems
Published on: March 3, 2010
Ru-porphyrin protein scaffolds for sensing O2
Michael B Winter1, Emily J McLaurin, Steven Y Reece
1Department of Chemistry, QB3 Institute, and Division of Physical Biosciences, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720-3220, USA.
None:
Hemoprotein-based scaffolds containing phosphorescent ruthenium(II) CO mesoporphyrin IX (RuMP) are reported here for oxygen (O(2)) sensing in biological contexts. RuMP was incorporated into the protein scaffolds during protein expression utilizing a novel method that we have described previously. A high-resolution (2.00 A) crystal structure revealed that the unnatural porphyrin binds to the proteins in a manner similar to the native heme and does not perturb the protein fold. The protein scaffolds were found to provide unique coordination environments for RuMP and modulate the porphyrin emission properties. Emission lifetime measurements demonstrate a linear O(2) response within the physiological range and precision comparable to commercial O(2) sensors. The RuMP proteins are robust, readily modifiable platforms and display promising O(2) sensing properties for future in vivo applications.
Related Concept Videos
Structure of Porins
Oxygenic Photosynthesis
Globular and Fibrous Proteins
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
The Photochemical Reaction Center

