Conformational stability and thermodynamic characterization of the lipoic acid bearing domain of human mitochondrial branched chain α-ketoacid dehydrogenase

Mandar T. Naik, Tai-huang Huang

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The lipoic acid bearing domain (hbLBD) of human mitochondrial branched chain α-ketoacid dehydrogenase (BCKD) plays important role of substrate channeling in oxidative decarboxylation of the branched chain α-ketoacids. Recently hbLBD has been found to follow two-step folding mechanism without detectable presence of stable or kinetic intermediates. The present study describes the conformational stability underlying the folding of this small β-barrel domain. Thermal denaturation in presence of urea and isothermal urea denaturation titrations are used to evaluate various thermodynamic parameters defining the equilibrium unfolding. The linear extrapolation model successfully describes the two-step; native state ↔ denatured state unfolding transition of hbLBD. The average temperature of maximum stability of hbLBD is estimated as 295.6 ± ;0.9 K. Cold denaturation of hbLBD is also predicted and discussed.

Original languageEnglish
Pages (from-to)2483-2492
Number of pages10
JournalProtein Science
Volume13
Issue number9
DOIs
Publication statusPublished - 2004 Sep 1

Fingerprint

Bearings (structural)
3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)
Thioctic Acid
Denaturation
Thermodynamics
Urea
Decarboxylation
Linear Models
Hot Temperature
Titration
Extrapolation
Temperature
Kinetics
Substrates

Keywords

  • BCKD
  • Branched chain α-keto-acid dehydrogenase
  • Lipoic acid bearing domain
  • MSUD
  • Maple syrup urine disease
  • Protein conformational stability
  • hbLBD

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology

Cite this

@article{e8b90c6fe35845ad959e1e599d1f2f20,
title = "Conformational stability and thermodynamic characterization of the lipoic acid bearing domain of human mitochondrial branched chain α-ketoacid dehydrogenase",
abstract = "The lipoic acid bearing domain (hbLBD) of human mitochondrial branched chain α-ketoacid dehydrogenase (BCKD) plays important role of substrate channeling in oxidative decarboxylation of the branched chain α-ketoacids. Recently hbLBD has been found to follow two-step folding mechanism without detectable presence of stable or kinetic intermediates. The present study describes the conformational stability underlying the folding of this small β-barrel domain. Thermal denaturation in presence of urea and isothermal urea denaturation titrations are used to evaluate various thermodynamic parameters defining the equilibrium unfolding. The linear extrapolation model successfully describes the two-step; native state ↔ denatured state unfolding transition of hbLBD. The average temperature of maximum stability of hbLBD is estimated as 295.6 ± ;0.9 K. Cold denaturation of hbLBD is also predicted and discussed.",
keywords = "BCKD, Branched chain α-keto-acid dehydrogenase, Lipoic acid bearing domain, MSUD, Maple syrup urine disease, Protein conformational stability, hbLBD",
author = "Naik, {Mandar T.} and Tai-huang Huang",
year = "2004",
month = "9",
day = "1",
doi = "10.1110/ps.04783104",
language = "English",
volume = "13",
pages = "2483--2492",
journal = "Protein Science",
issn = "0961-8368",
publisher = "Cold Spring Harbor Laboratory Press",
number = "9",

}

TY - JOUR

T1 - Conformational stability and thermodynamic characterization of the lipoic acid bearing domain of human mitochondrial branched chain α-ketoacid dehydrogenase

AU - Naik, Mandar T.

AU - Huang, Tai-huang

PY - 2004/9/1

Y1 - 2004/9/1

N2 - The lipoic acid bearing domain (hbLBD) of human mitochondrial branched chain α-ketoacid dehydrogenase (BCKD) plays important role of substrate channeling in oxidative decarboxylation of the branched chain α-ketoacids. Recently hbLBD has been found to follow two-step folding mechanism without detectable presence of stable or kinetic intermediates. The present study describes the conformational stability underlying the folding of this small β-barrel domain. Thermal denaturation in presence of urea and isothermal urea denaturation titrations are used to evaluate various thermodynamic parameters defining the equilibrium unfolding. The linear extrapolation model successfully describes the two-step; native state ↔ denatured state unfolding transition of hbLBD. The average temperature of maximum stability of hbLBD is estimated as 295.6 ± ;0.9 K. Cold denaturation of hbLBD is also predicted and discussed.

AB - The lipoic acid bearing domain (hbLBD) of human mitochondrial branched chain α-ketoacid dehydrogenase (BCKD) plays important role of substrate channeling in oxidative decarboxylation of the branched chain α-ketoacids. Recently hbLBD has been found to follow two-step folding mechanism without detectable presence of stable or kinetic intermediates. The present study describes the conformational stability underlying the folding of this small β-barrel domain. Thermal denaturation in presence of urea and isothermal urea denaturation titrations are used to evaluate various thermodynamic parameters defining the equilibrium unfolding. The linear extrapolation model successfully describes the two-step; native state ↔ denatured state unfolding transition of hbLBD. The average temperature of maximum stability of hbLBD is estimated as 295.6 ± ;0.9 K. Cold denaturation of hbLBD is also predicted and discussed.

KW - BCKD

KW - Branched chain α-keto-acid dehydrogenase

KW - Lipoic acid bearing domain

KW - MSUD

KW - Maple syrup urine disease

KW - Protein conformational stability

KW - hbLBD

UR - http://www.scopus.com/inward/record.url?scp=4344622456&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=4344622456&partnerID=8YFLogxK

U2 - 10.1110/ps.04783104

DO - 10.1110/ps.04783104

M3 - Article

VL - 13

SP - 2483

EP - 2492

JO - Protein Science

JF - Protein Science

SN - 0961-8368

IS - 9

ER -