Imaging bacterial peptidoglycan with near-infrared fluorogenic azide probes.
Fluorescent probes designed for activation by bioorthogonal chemistry have enabled the visualization of biomolecules in living systems. Such activatable probes with near-infrared (NIR) emission would be ideal for in vivo imaging but have proven difficult to engineer. We present the development of NIR fluorogenic azide probes based on the Si-rhodamine scaffold that undergo a fluorescence enhancement of up to 48-fold upon reaction with terminal or strained alkynes. We used the probes for mammalian cell surface imaging and, in conjunction with a new class of cyclooctyne D-amino acids, for visualization of bacterial peptidoglycan without the need to wash away unreacted probe.
Departments of Chemistry and Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, CA 94720.
Peyton
P
Shieh
M Sloan
MS
Siegrist
Andrew J
AJ
Cullen
Carolyn R
CR
Bertozzi
D001386:Azides; D005456:Fluorescent Dyes; D057054:Molecular Imaging / Q000379:methods*; D015336:Molecular Probe Techniques; D015394:Molecular Structure; D010457:Peptidoglycan / Q000737:chemistry / Q000648:ultrastructure*
D001386:Azides; D005456:Fluorescent Dyes; D010457:Peptidoglycan