TY - JOUR
T1 - Two-photon excitation of a phytofluor protein
AU - Gryczynski, Ignacy
AU - Piszczek, Gregorz
AU - Lakowicz, Joseph R.
AU - Lagarias, J. Clark
N1 - Funding Information:
This work was supported by the NIH, National Center for Research Resources, RR-08119 (JRL) and by NSF (MCB 96-04511) to JCL.
PY - 2002/7/26
Y1 - 2002/7/26
N2 - Phytofluors are highly fluorescent proteins in which the chromophore in a phytochrome is replaced with phycoerythrobilin (PEB), the pigment precursor of the cyanobacterial light harvesting protein phycoerythrin. We examined the fluorescence spectra of the N-terminal region of the cyanobacterial phytochrome 1 from cyanobacterium Synechocystis sp. Pcc 6803 bound to PEB. This protein, Cph1(N514)-PEB, displayed a good two-photon cross-section of 20-30 GM for excitation at 792 nm. This phytofluor also exhibits a high fundamental anisotropy at most practical two-photon excitation (2PE) wavelengths from 700 to 900 nm. Identical lifetimes and correlation times with one and 2PE indicates that the phytofluor is not adversely affected by the intensities needed for 2PE. The one-photon absorption extends well beyond the absorption spectrum and even beyond the emission spectrum to 700 nm. The phytofluor thus appears to be a suitable probe for 2PE and/or cellular imaging.
AB - Phytofluors are highly fluorescent proteins in which the chromophore in a phytochrome is replaced with phycoerythrobilin (PEB), the pigment precursor of the cyanobacterial light harvesting protein phycoerythrin. We examined the fluorescence spectra of the N-terminal region of the cyanobacterial phytochrome 1 from cyanobacterium Synechocystis sp. Pcc 6803 bound to PEB. This protein, Cph1(N514)-PEB, displayed a good two-photon cross-section of 20-30 GM for excitation at 792 nm. This phytofluor also exhibits a high fundamental anisotropy at most practical two-photon excitation (2PE) wavelengths from 700 to 900 nm. Identical lifetimes and correlation times with one and 2PE indicates that the phytofluor is not adversely affected by the intensities needed for 2PE. The one-photon absorption extends well beyond the absorption spectrum and even beyond the emission spectrum to 700 nm. The phytofluor thus appears to be a suitable probe for 2PE and/or cellular imaging.
KW - Green fluorescent protein
KW - One-photon excitation
KW - Two-photon excitation
UR - http://www.scopus.com/inward/record.url?scp=0037178606&partnerID=8YFLogxK
U2 - 10.1016/S1010-6030(02)00021-7
DO - 10.1016/S1010-6030(02)00021-7
M3 - Article
AN - SCOPUS:0037178606
SN - 1010-6030
VL - 150
SP - 13
EP - 19
JO - Journal of Photochemistry and Photobiology, A: Chemistry
JF - Journal of Photochemistry and Photobiology, A: Chemistry
IS - 1-3
ER -