Singlet oxygen photosensitisation by GFP mutants: oxygen accessibility to the chromophore.
Aiming at the rational development of genetically-encoded photosensitisers, the production of singlet oxygen has been assessed for a number of class-2 Green Fluorescent Protein (GFP) mutants by means of time-resolved near-infrared luminescence detection. The accessibility of molecular oxygen to the chromophore seems to play a major role in the ability of GFPs to photosensitise singlet oxygen and this can be modulated by introducing specific mutations such as replacement of His148 by a less bulky amino acid. GFPs are also good singlet oxygen quenchers, hence further developments in this area should also seek to eliminate those amino acids with the highest quenching ability, particularly those at the protein surface and in the vicinity of the chromophore.
Jiménez-Banzo
Ana
A
Grup d'Engiyneria Molecular, Institut Químic de Sarrià, Via Augusta 390, 08017, Barcelona, Spain.
Ragàs
Xavier
X
Abbruzzetti
Stefania
S
Viappiani
Cristiano
C
Campanini
Barbara
B
Flors
Cristina
C
Nonell
Santi
S
D019943:Amino Acid Substitution; D049452:Green Fluorescent Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D053844:Lasers, Solid-State; D049408:Luminescent Agents / Q000737:chemistry*; D016297:Mutagenesis, Site-Directed; D010100:Oxygen / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D026082:Singlet Oxygen / Q000737:chemistry / Q000378:metabolism*; D013053:Spectrophotometry
D049408:Luminescent Agents; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins; D026082:Singlet Oxygen; D010100:Oxygen