creators_name: Kumar, Rajesh
creators_name: Sharma, Deepak
creators_name: Kumar, Navinder
creators_name: Kumari, Beeta
creators_name: Shabnam, .
creators_name: Kumar, Sanjeev
creators_name: Kumar, Rajesh
type: article
datestamp: 2024-07-15 03:58:15
lastmod: 2024-07-15 03:58:20
metadata_visibility: show
title: Substitution of carbonate by non-physiological synergistic anion modulates the stability and iron release kinetics of serum transferrin. 
ispublished: pub
subjects: QR
keywords:  Activation enthalpy; Iron release; Reduction-induced iron release; Stability of iron centers; Structural stability; Synergistic anions.
note: The copyright of this article belongs to ELSEVIER
abstract: Serum transferrin (sTf) is a bi-lobal protein. Each lobe of sTf binds one Fe3+ ion in the presence of a synergistic anion. Physiologically, carbonate is the main synergistic anion but other anions such as oxalate, malonate, glycolate, maleate, glycine, etc. can substitute for carbonate in vitro. The present work provides the possible pathways by which the substitution of carbonate with oxalate affects the structural, kinetic, thermodynamic, and functional properties of blood plasma sTf. Analysis of equilibrium experiments measuring iron release and structural unfolding of carbonate and oxalate bound diferric-sTf (Fe2sTf) as a function of pH, urea concentration, and temperature reveal that the structural and iron-centers stability of Fe2sTf increase by substitution of carbonate with oxalate. Analysis of isothermal titration calorimetry (ITC) scans showed that the affinity of Fe3+ with apo-sTf is enhanced by substituting carbonate with oxalate. Analysis of kinetic and thermodynamic parameters measured for the iron release from the carbonate and oxalate bound monoferric-N-lobe of sTf (FeNsTf) and Fe2sTf at pH 7.4 and pH 5.6 reveals that the substitution of carbonate with oxalate inhibits/retards the iron release via increasing the enthalpic barriers.


date: 2022-10
date_type: published
publication: Biochimica et biophysica acta
volume: 1871
number: 1
publisher: ELSEVIER 
id_number: 10.1016/j.bbapap.2022.140856
refereed: TRUE
issn: 0006-3002
official_url: https://www.sciencedirect.com/science/article/pii/S1570963922001030?via%3Dihub
citation:   Kumar, Rajesh and Sharma, Deepak and Kumar, Navinder and Kumari, Beeta and Shabnam, . and Kumar, Sanjeev and Kumar, Rajesh  (2022) Substitution of carbonate by non-physiological synergistic anion modulates the stability and iron release kinetics of serum transferrin.  Biochimica et biophysica acta, 1871 (1).   ISSN 0006-3002