Fluorescence emission properties of S-Layer enhanced green fluorescent fusion protein as a function of temperature, pH conditions, and guanidine hydrochloride concentration.
The fluorescent properties of the S-layer enhanced green fluorescent fusion protein (rSbpA31-1068/EGFP) were investigated as a function of temperature, pH conditions, and guanidine hydrochloride concentration. These results were compared to the fluorescent properties of the recombinant enhanced green fluorescent protein (EGFP) and an equimolar mixture of the S-layer protein rSbpA and EGFP. The intensity of the fluorescence emission of the EGFP at 510 nm, after excitation at 490 nm, is not affected by the presence of rSbpA, either as a fusion partner or as a free protein in solution. In each of the three protein systems, the emission intensity at 510 nm reaches its maximum value between pH 7 and 9 at 20 degrees C and at 0 M guanidine hydrochloride. No fluorescence could be measured at pH 4 and 6 M guanidine hydrochloride. These results show that the S-layer fusion protein (rSbpA31-1068/EGFP) is a suitable candidate for future applications in nanobiotechonology at a wide range of pH, temperature, and guanidine hydrochloride concentrations.
Toca-Herrera
José L
JL
Department of Chemical Engineering, Rovira i Virgili University, Av. Paisos Catalans, 43003 Tarragona, Spain, Biosurfaces Unit, CICBiomagune, Paseo Miramon 182, 20009 San Sebastian, Spain. joseluis.toca@urv.net
Küpcü
Seta
S
Diederichs
Valerie
V
Moncayo
Gerald
G
Pum
Dietmar
D
Sleytr
Uwe B
UB
D049452:Green Fluorescent Proteins / Q000032:analysis / Q000737:chemistry*; D019791:Guanidine; D006863:Hydrogen-Ion Concentration; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods; D013816:Thermodynamics
D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D019791:Guanidine