Conserved cysteine residues provide a protein-protein interaction surface in dual oxidase (DUOX) proteins.

J Biol Chem

Laboratory of Molecular Pharmacology of the Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA.

Published: March 2013

AI Article Synopsis

  • Intramolecular disulfide bonds are crucial for protein stability and function, particularly in the oxidizing environments of the extracellular space and endoplasmic reticulum.
  • The DUOX1 and DUOX2 proteins have unique extracellular regions that lack the structural cysteines common in other peroxidases, leading to theories that their thiol groups may not support disulfide bond formation.
  • Mutations in these thiol residues did not significantly impact protein stability but affected dimerization and reduced H2O2 production, indicating that these cysteines play a role in protein interactions vital for enzyme localization and function.

Article Abstract

Intramolecular disulfide bond formation is promoted in oxidizing extracellular and endoplasmic reticulum compartments and often contributes to protein stability and function. DUOX1 and DUOX2 are distinguished from other members of the NOX protein family by the presence of a unique extracellular N-terminal region. These peroxidase-like domains lack the conserved cysteines that confer structural stability to mammalian peroxidases. Sequence-based structure predictions suggest that the thiol groups present are solvent-exposed on a single protein surface and are too distant to support intramolecular disulfide bond formation. To investigate the role of these thiol residues, we introduced four individual cysteine to glycine mutations in the peroxidase-like domains of both human DUOXs and purified the recombinant proteins. The mutations caused little change in the stabilities of the monomeric proteins, supporting the hypothesis that the thiol residues are solvent-exposed and not involved in disulfide bonds that are critical for structural integrity. However, the ability of the isolated hDUOX1 peroxidase-like domain to dimerize was altered, suggesting a role for these cysteines in protein-protein interactions that could facilitate homodimerization of the peroxidase-like domain or, in the full-length protein, heterodimeric interactions with a maturation protein. When full-length hDUOX1 was expressed in HEK293 cells, the mutations resulted in decreased H2O2 production that correlated with a decreased amount of the enzyme localized to the membrane surface rather than with a loss of activity or with a failure to synthesize the mutant proteins. These results support a role for the cysteine residues in intermolecular disulfide bond formation with the DUOX maturation factor DUOXA1.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3591624PMC
http://dx.doi.org/10.1074/jbc.M112.414797DOI Listing

Publication Analysis

Top Keywords

disulfide bond
12
bond formation
12
cysteine residues
8
intramolecular disulfide
8
peroxidase-like domains
8
thiol residues
8
peroxidase-like domain
8
protein
5
conserved cysteine
4
residues
4

Similar Publications

KNG1 mutations (c.618 T > G and c.1165C > T) cause disruption of the Cys206-Cys218 disulfide bond and truncation of the D5 domain leading to hereditary high molecular weight kininogen deficiency.

Clin Biochem

January 2025

Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Nanning, Guangxi, China; Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China; Key Laboratory of Hematology, Guangxi Medical University, Education Department of Guangxi Zhuang Autonomous Region, Nanning, Guangxi, China. Electronic address:

Background: High molecular weight kininogen (HMWK), encoded by the kininogen-1 (KNG1) gene, is a multifunctional glycoprotein closely associated with the initiation of blood coagulation, tumor growth, and other pathological processes.

Objective: We conducted a study on the clinical phenotype, genetic mutations, and molecular pathogenesis of a female patient with uterine leiomyosarcoma, who presented with HMWK deficiency and an isolated prolonged activated partial thromboplastin time (APTT).

Methods: Clinical phenotyping was conducted through APTT mixing studies, quantitative assessments of intrinsic coagulation factor activities, antigen levels of HMWK, and thromboelastography.

View Article and Find Full Text PDF

The protein therapeutics market, including antibody and fusion proteins, has experienced steady growth over the past decade, underscoring the importance of optimizing amino acid sequences. In our previous study, we developed a fusion protein, R31, which combines retinol-binding protein (RBP) with albumin domains IIIA and IB, linked by a sequence (AAAA), and includes an additional disulfide bond (N227C-V254C) in IIIA. This fusion protein effectively inhibited hepatic stellate cell activation.

View Article and Find Full Text PDF

Host defense antimicrobial peptides (AMPs) are promising lead molecules with which to develop antibiotics against drug-resistant bacterial pathogens. Thanatin, an inducible antimicrobial peptide involved in the host defense of insects, is gaining considerable attention in the generation of novel classes of antibiotics. Thanatin or thanatin-based analog peptides are extremely potent in killing bacterial pathogens in the Enterobacteriaceae family, including drug-resistant strains of and .

View Article and Find Full Text PDF

In recent years, plasma medicine has developed rapidly as a new interdisciplinary discipline. However, the key mechanisms of interactions between cold atmospheric plasma (CAP) and biological tissue are still in the exploration stage. In this study, by introducing the reactive molecular dynamics (MD) simulation, the capsid protein (CA) molecule of HIV was selected as the model to investigate the reaction process upon impact by reactive oxygen species (ROS) from CAP and protein molecules at the atomic level.

View Article and Find Full Text PDF

Molecular basis of interchain disulfide bond formation in BMP-9 and BMP-10.

J Mol Biol

January 2025

Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA. Electronic address:

BMP-9 and BMP-10 are TGF-β family signaling ligands naturally secreted into blood. They act on endothelial cells and are required for proper development and maintenance of the vasculature. In hereditary hemorrhagic telangiectasia, regulation is disrupted due to mutations in the BMP-9/10 pathway, namely in the type I receptor ALK1 or the co-receptor endoglin.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!