Investigation of Protein-Protein Interactions of Ferredoxin and Sulfite Reductase Under Different Sodium Chloride Concentrations by NMR Spectroscopy and Isothermal Titration Calorimetry

Kim, Ju Yaen; Ikegami, Takahisa; Goto, Yuji; Hase, Toshiharu; Lee, Young-Ho

doi:10.1007/978-3-319-20137-5_17

Cited by 2 publications

(1 citation statement)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…bond formation), providing accurate, rapid and label free thermodynamic data to determine the changes in enthalpy ΔH, entropy ΔS, and Gibbs free energy ΔG of the adsorption process, as well as provide information on the affinity binding constant K d and the interaction reaction stoichiometry in a single titration experiment. 34 This advanced technology has been widely applied in the chemical and biochemical fields to study protein interactions 35,36 and macromolecular assembly, 37 protein membrane interactions, 38 enzyme kinetics, 39 molecular dynamics simulations, 40 and incremental and DNA-ligand binding. 41 Karlsen et al (2010) conducted a very general study to investigate the use of ITC to determine the thermodynamics of Al 3+ , Cr 3+ , and Pb 2+ binding to the biopolymer chitin, and found that the binding reactions were entropically driven.…”

Section: -14mentioning

confidence: 99%

Isothermal titration microcalorimetry to determine the thermodynamics of metal ion removal by magnetic nanoparticle sorbents

Huang

Keller

2016

Environ. Sci.: Nano

View full text Add to dashboard Cite

show abstract

Section: -14mentioning

confidence: 99%

Isothermal titration microcalorimetry to determine the thermodynamics of metal ion removal by magnetic nanoparticle sorbents

Huang

Keller

2016

Environ. Sci.: Nano

View full text Add to dashboard Cite

show abstract

Non-covalent forces tune the electron transfer complex between ferredoxin and sulfite reductase to optimize enzymatic activity

Kim

Kinoshita

Kume³

et al. 2016

Biochemical Journal

View full text Add to dashboard Cite

Although electrostatic interactions between negatively charged ferredoxin (Fd) and positively charged sulfite reductase (SiR) have been predominantly highlighted to characterize complex formation, the detailed nature of intermolecular forces remains to be fully elucidated. We investigated interprotein forces for the formation of an electron transfer complex between Fd and SiR and their relationship to SiR activity using various approaches over NaCl concentrations between 0 and 400 mM. Fd-dependent SiR activity assays revealed a bell-shaped activity curve with a maximum ∼40-70 mM NaCl and a reverse bell-shaped dependence of interprotein affinity. Meanwhile, intrinsic SiR activity, as measured in a methyl viologen-dependent assay, exhibited saturation above 100 mM NaCl. Thus, two assays suggested that interprotein interaction is crucial in controlling Fd-dependent SiR activity. Calorimetric analyses showed the monotonic decrease in interprotein affinity on increasing NaCl concentrations, distinguished from a reverse bell-shaped interprotein affinity observed from Fd-dependent SiR activity assay. Furthermore, Fd:SiR complex formation and interprotein affinity were thermodynamically adjusted by both enthalpy and entropy through electrostatic and non-electrostatic interactions. A residue-based NMR investigation on the addition of SiR to N-labeled Fd at the various NaCl concentrations also demonstrated that a combination of electrostatic and non-electrostatic forces stabilized the complex with similar interfaces and modulated the binding affinity and mode. Our findings elucidate that non-electrostatic forces are also essential for the formation and modulation of the Fd:SiR complex. We suggest that a complex configuration optimized for maximum enzymatic activity near physiological salt conditions is achieved by structural rearrangement through controlled non-covalent interprotein interactions.

show abstract

Investigation of Protein-Protein Interactions of Ferredoxin and Sulfite Reductase Under Different Sodium Chloride Concentrations by NMR Spectroscopy and Isothermal Titration Calorimetry

Cited by 2 publications

References 9 publications

Isothermal titration microcalorimetry to determine the thermodynamics of metal ion removal by magnetic nanoparticle sorbents

Isothermal titration microcalorimetry to determine the thermodynamics of metal ion removal by magnetic nanoparticle sorbents

Non-covalent forces tune the electron transfer complex between ferredoxin and sulfite reductase to optimize enzymatic activity

Contact Info

Product

Resources

About