@conference{
author = "Radomirović, Mirjana and Gligorijević, Nikola and Minić, Simeon and Nikolić, Milan and Stanić-Vučinić, Dragana and Ćirković-Veličković, Tanja",
year = "2021",
abstract = "Phycobiliproteins (PBP) have been employed in numerous fluorescence-based techniques owing
to highly fluorescent, covalently bound tetrapyrrole chromophores. So far, only entire PBPs have
been utilized as fluorescent probes. A new method for covalent attachment of phycocyanin’s
chromophore, phycocyanobilin (PCB), to potentially any protein, is proposed, relying on the
ability of PCB to be attached to sulfhydryl groups of proteins. Traut’s reagent (TR, 2-
iminothiolane) was exploited for introduction of sulfhydryl groups in the model protein, bovine
serum albumin (BSA), by modifying its primary amines. Introduced sulfhydryl groups were then
targeted for modification by PCB. All tested molar ratios of TR per mole of protein were
successful in modification of BSA. Near-UV and far-UV circular dichroism spectroscopy
revealed that a higher degree of modification by TR induces more profound alterations of BSA
structure, leading at the same time to minor changes in BSA oligomerization and aggregation
profile. PCB was covalently attached to introduced sulfhydryl groups at pH 9 at 20–fold ratio of
TR. An increase in the molar ratio of TR per mole of BSA leads to amplification of fluorescent
signal of PCB-modified BSA, most significantly observed starting from 50-fold and higher TR
ratios. Using BSA as a model protein, a 50-fold molar excess of TR seems to be the optimal ratio
for balancing between the effect on protein structure and the degree of labeling and thus
fluorescent signal obtained. The proposed method could be used for labeling of virtually any
protein, as means of either obtaining fluorescent probes for application in fluorescent techniques
or functionalization of, for example, food proteins through covalent attachment of bioactive
PCB.",
publisher = "University of Belgrade - Faculty of Chemistry",
journal = "FoodEnTwin Symposium “Novel analytical approaches in food and environmental sciences”, Book of Abstracts, 16th-18th June, 2021, Belgrade, Serbia",
title = "Traut’s reagent application in fluorescent labeling of bovine serum albumin with phycocyanobilin",
pages = "37-37",
url = "https://hdl.handle.net/21.15107/rcub_cer_7282"
}