Incorporation of a molybdenum atom in a Rubredoxin-type Centre of a de novo-designed α3DIV-L21C three-helical bundle peptide

Pedro M S Bragança; Marta S P Carepo; Sofia R Pauleta; Tyler B J Pinter; Maddalena Elia; Cristina M Cordas; Isabel Moura; Vincent L Pecoraro; José J G Moura

doi:10.1016/j.jinorgbio.2022.112096

Incorporation of a molybdenum atom in a Rubredoxin-type Centre of a de novo-designed α₃DIV-L21C three-helical bundle peptide

J Inorg Biochem. 2023 Mar:240:112096. doi: 10.1016/j.jinorgbio.2022.112096. Epub 2022 Dec 22.

Authors

Pedro M S Bragança¹, Marta S P Carepo², Sofia R Pauleta³, Tyler B J Pinter⁴, Maddalena Elia⁵, Cristina M Cordas⁵, Isabel Moura⁵, Vincent L Pecoraro⁴, José J G Moura⁶

Affiliations

¹ LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal; Microbial Stress Lab, UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal; Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
² LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal; Escola de Psicologia e Ciências da Vida, Departamento de Ciências da Vida, Universidade Lusófona de Humanidades e Tecnologias, Campo Grande, 1749-024 Lisboa, Portugal. Electronic address: marta.carepo@fct.unl.pt.
³ Microbial Stress Lab, UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal; Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
⁴ Department of Chemistry and Biophysics, University of Michigan, Ann Arbor, MI 48109-1055, United States.
⁵ LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
⁶ LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal. Electronic address: jose.moura@fct.unl.pt.

PMID: 36603242
DOI: 10.1016/j.jinorgbio.2022.112096

Abstract

The rational design and functionalization of small, simple, and stable peptides scaffolds is an attractive avenue to mimic catalytic metal-centres of complex proteins, relevant for the design of metalloenzymes with environmental, biotechnological and health impacts. The de novo designed α₃DIV-L21C framework has a rubredoxin-like metal binding site and was used in this work to incorporate a Mo-atom. Thermostability studies using differential scanning calorimetry showed an increase of 4 °C in the melting temperature of the Mo-α₃DIV-L21C when compared to the apo-α₃DIV-L21C. Circular dichroism in the visible and far-UV regions corroborated these results showing that Mo incorporation provides stability to the peptide even though there were almost no differences observed in the secondary structure. A formal reduction potential of ∼ -408 mV vs. NHE, pH 7.6 was determined. Combining electrochemical results, EPR and UV-visible data we discuss the oxidation state of the molybdenum centre in Mo-α₃DIV-L21C and propose that is mainly in a Mo (VI) oxidation state.

Keywords: A de novo protein design; Models of molybdenum-containing enzymes; Molybdenum; Rubredoxin; Tetracysteinyl coordination; Three-helix bundle.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Metalloproteins* / chemistry
Molybdenum* / chemistry
Oxidation-Reduction
Peptides / metabolism
Rubredoxins / metabolism

Substances

Molybdenum
Rubredoxins
Metalloproteins
Peptides