A molecular magnet confined in the nanocage of a globular protein.
The effect of confinement and energy transfer on the dynamics of a molecular magnet, known as a model system to study quantum coherence, is investigated. For this purpose the well-known polyoxovanadate [V(15)As(6)O(42)(H(2)O)](6-) (V(15)) is incorporated into a protein (human serum albumin, HSA) cavity. Due to a huge overlap of the optical absorption spectrum of V(15) with the emission spectrum of a fluorescence center of HSA (containing a single tryptophan residue), energy transfer is induced and probed by steady-state and time-resolved fluorescence. The geometrical coordination and the distance of the confined V(15) to the tryptophan moiety of HSA are investigated at various temperatures. This effect is used as a local probe for the thermal denaturation of the protein at elevated temperatures.
Mitra
Rajib K
RK
Unit for Nano Science and Technology, Department for Chemical, Biological and Macromolecular Sciences, S.N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700098, India.
Verma
Pramod K
PK
Wulferding
Dirk
D
Menzel
Dirk
D
Mitra
Tamoghna
T
Todea
Ana M
AM
Lemmens
Peter
P
Müller
Achim
A
Pal
Samir K
SK
D001665:Binding Sites; D004735:Energy Transfer; D006801:Humans; D008280:Magnetics; D015394:Molecular Structure; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D012709:Serum Albumin / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013696:Temperature; D013816:Thermodynamics
D012709:Serum Albumin