albumin - publications

Predict more albumin - ligand interactions now!

1. Colloids Surf B Biointerfaces. 2012 Feb 22. [Epub ahead of print]

Study on effect of lipophilic curcumin on sub-domain IIA site of human serum
albumin during unfolded and refolded states: A synchronous fluorescence
spectroscopic study.

Patra D, Barakat C, Tafech RM.

Department of Chemistry, American University of Beirut, Beirut 1107-2020,

Curcumin having pharmaceutical application as anti-oxidant, anti-inflammatory and
anti-carcinogenic drug necessitates studying interaction of this molecule with
native, unfolded and refolded state of human serum albumin (HSA), carrier protein
in the blood. We proposed a simultaneous static and dynamic fluorescence
quenching mechanism operating in the complex formation between HSA and curcumin.
Location of curcumin in the close proximity of tryptophan with respect to
tyrosine was further evident from the observation of two fold increase in rate of
depletion of SFS intensity for tryptophan with respect to tyrosine in HSA in SFS
spectrum. Alteration of SFS spectral peak position, electronic absorbance,
fluorescence intensity and lifetime suggested chemical denaturation by urea
expectedly unfold the protein molecule in the absence and presence of curcumin.
Denatured HSA had similar fluorescence peak position and lifetime to that of
l-tryptophan in the polar environment. During unfolding of HSA the spectral
change of tyrosine and tryptophan was resolved through synchronous fluorescence
spectra at two different Δλ in absence and presence of curcumin. It is found that
curcumin remained bound to unfolded state of HSA and facilitated the process by
pushing tryptophan moiety to more polar environment in the unfolded state.
Dilution of the denatured protein by phosphate buffer reversibly refolded the
sub-domain IIA, by also recovering fluorescence lifetime loss, but it was slow in
the presence of curcumin. k(q) values indicate that curcumin-HSA complex is
formed in the unfolded and refolded states as observed for native state.

Copyright © 2012 Elsevier B.V. All rights reserved.

PMID: 22398366 [PubMed - as supplied by publisher]