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Thapa P, Jiang H, Ding N, Hao Y, Alshahrani A, Wei Q. The Role of Peroxiredoxins in Cancer Development. BIOLOGY 2023; 12:666. [PMID: 37237480 PMCID: PMC10215932 DOI: 10.3390/biology12050666] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/21/2023] [Accepted: 04/26/2023] [Indexed: 05/28/2023]
Abstract
Peroxiredoxins (Prxs) are antioxidant enzymes with ubiquitous expression in human tissues. Prxs are expressed in archaea, bacteria, and eukaryota, often in multiple isoforms. Because of their abundant expression in different cellular organelles and extraordinary sensitivity to H2O2, Prxs are among the first defenses against oxidative stress. Prxs undergo reversible oxidation to disulfides, and some family members perform chaperone or phospholipase functions upon further oxidation. Prxs are upregulated in cancer cells. Research has suggested that Prxs can function as tumor promoters in various cancers. The major objective of this review is to summarize novel findings regarding the roles of Prxs in common cancer types. Prxs have been shown to influence differentiation of inflammatory cells and fibroblasts, remodeling of extracellular matrix, and regulation of stemness. Since aggressive cancer cells have higher intracellular levels of ROS that they can utilize to proliferate and metastasize compared to normal cells, it is critical that we understand the regulation and functions of primary antioxidants such as Prxs. These small but mighty proteins could prove to be key for improving cancer therapeutics and patient survival.
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Affiliation(s)
- Pratik Thapa
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, 1095 Veterans Dr, Lexington, KY 40508, USA
| | - Hong Jiang
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, 1095 Veterans Dr, Lexington, KY 40508, USA
| | - Na Ding
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, 1095 Veterans Dr, Lexington, KY 40508, USA
| | - Yanning Hao
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, 1095 Veterans Dr, Lexington, KY 40508, USA
| | - Aziza Alshahrani
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, 1095 Veterans Dr, Lexington, KY 40508, USA
| | - Qiou Wei
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, 1095 Veterans Dr, Lexington, KY 40508, USA
- Markey Cancer Center, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY 40536, USA
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2
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Uehara H, Itoigawa Y, Wada T, Morikawa D, Koga A, Nojiri H, Kawasaki T, Maruyama Y, Ishijima M. Relationship of superoxide dismutase to rotator cuff injury/tear in a rat model. J Orthop Res 2022; 40:1006-1015. [PMID: 34185341 DOI: 10.1002/jor.25141] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 05/04/2021] [Accepted: 06/25/2021] [Indexed: 02/04/2023]
Abstract
Rotator cuff degeneration is one of the several factors that lead to rotator cuff tears. Oxidative stress and superoxide dismutase have been reported to be related to rotator cuff degeneration; however, the precise mechanism still remains unclear. In this study, we investigated the relationship of oxidative stress and superoxide dismutase to the degeneration of the rotator cuff using rat models. Eighty-four rats were used to create a collagenase-induced rotator cuff injury model (injury model) and a rotator cuff tear model (tear model). The controls were administered saline and had only a deltoid incision, respectively. We evaluated degeneration morphology of the rotator cuff using a degeneration score; dihydroethidium fluorescence intensity, which detects oxidative stress; gene expression; and superoxide dismutase activity. The rotator cuffs in the injury and tear models significantly increased degeneration scores and dihydroethidium fluorescence intensity. On the other hand, gene expression of superoxide dismutase isoform, superoxide dismutase 1, and superoxide dismutase activity were significantly decreased in the injury model but showed no significant difference in the tear model. These findings suggested that superoxide dismutase might not be associated with rotator cuff degeneration after tear but may be involved in degenerative rotator cuff without tear. However, we found that rotator cuff degeneration involves oxidative stress both with and without tear. Based on these findings, it is presumed that different treatments may be appropriate, depending on the state of rotator cuff degeneration, because the mechanisms of the degeneration may be different.
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Affiliation(s)
- Hirohisa Uehara
- Department of Orthopaedic Surgery, Juntendo University Urayasu Hospital, Chiba, Japan.,Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yoshiaki Itoigawa
- Department of Orthopaedic Surgery, Juntendo University Urayasu Hospital, Chiba, Japan
| | - Tomoki Wada
- Department of Orthopaedic Surgery, Juntendo University Urayasu Hospital, Chiba, Japan
| | - Daichi Morikawa
- Department of Orthopaedic Surgery, Juntendo University Urayasu Hospital, Chiba, Japan
| | - Akihisa Koga
- Department of Orthopaedic Surgery, Juntendo University Urayasu Hospital, Chiba, Japan
| | - Hidetoshi Nojiri
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takayuki Kawasaki
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yuichiro Maruyama
- Department of Orthopaedic Surgery, Juntendo University Urayasu Hospital, Chiba, Japan
| | - Muneaki Ishijima
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan
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3
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Bioinformatic Analyses of Peroxiredoxins and RF-Prx: A Random Forest-Based Predictor and Classifier for Prxs. Methods Mol Biol 2022; 2499:155-176. [PMID: 35696080 PMCID: PMC9844236 DOI: 10.1007/978-1-0716-2317-6_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Peroxiredoxins (Prxs) are a protein superfamily, present in all organisms, that play a critical role in protecting cellular macromolecules from oxidative damage but also regulate intracellular and intercellular signaling processes involving redox-regulated proteins and pathways. Bioinformatic approaches using computational tools that focus on active site-proximal sequence fragments (known as active site signatures) and iterative clustering and searching methods (referred to as TuLIP and MISST) have recently enabled the recognition of over 38,000 peroxiredoxins, as well as their classification into six functionally relevant groups. With these data providing so many examples of Prxs in each class, machine learning approaches offer an opportunity to extract additional information about features characteristic of these protein groups.In this study, we developed a novel computational method named "RF-Prx" based on a random forest (RF) approach integrated with K-space amino acid pairs (KSAAP) to identify peroxiredoxins and classify them into one of six subgroups. Our process performed in a superior manner compared to other machine learning classifiers. Thus the RF approach integrated with K-space amino acid pairs enabled the detection of class-specific conserved sequences outside the known functional centers and with potential importance. For example, drugs designed to target Prx proteins would likely suffer from cross-reactivity among distinct Prxs if targeted to conserved active sites, but this may be avoidable if remote, class-specific regions could be targeted instead.
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4
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Rice Lesion Mimic Mutants (LMM): The Current Understanding of Genetic Mutations in the Failure of ROS Scavenging during Lesion Formation. PLANTS 2021; 10:plants10081598. [PMID: 34451643 PMCID: PMC8400881 DOI: 10.3390/plants10081598] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/26/2021] [Accepted: 07/30/2021] [Indexed: 01/02/2023]
Abstract
Rice lesion mimic mutants (LMMs) form spontaneous lesions on the leaves during vegetative growth without pathogenic infections. The rice LMM group includes various mutants, including spotted leaf mutants, brown leaf mutants, white-stripe leaf mutants, and other lesion-phenotypic mutants. These LMM mutants exhibit a common phenotype of lesions on the leaves linked to chloroplast destruction caused by the eruption of reactive oxygen species (ROS) in the photosynthesis process. This process instigates the hypersensitive response (HR) and programmed cell death (PCD), resulting in lesion formation. The reasons for lesion formation have been studied extensively in terms of genetics and molecular biology to understand the pathogen and stress responses. In rice, the lesion phenotypes of most rice LMMs are inherited according to the Mendelian principles of inheritance, which remain in the subsequent generations. These rice LMM genetic traits have highly developed innate self-defense mechanisms. Thus, although rice LMM plants have undesirable agronomic traits, the genetic principles of LMM phenotypes can be used to obtain high grain yields by deciphering the efficiency of photosynthesis, disease resistance, and environmental stress responses. From these ailing rice LMM plants, rice geneticists have discovered novel proteins and physiological causes of ROS in photosynthesis and defense mechanisms. This review discusses recent studies on rice LMMs for the Mendelian inheritances, molecular genetic mapping, and the genetic definition of each mutant gene.
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5
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Andreadou I, Efentakis P, Frenis K, Daiber A, Schulz R. Thiol-based redox-active proteins as cardioprotective therapeutic agents in cardiovascular diseases. Basic Res Cardiol 2021; 116:44. [PMID: 34275052 DOI: 10.1007/s00395-021-00885-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 06/17/2021] [Indexed: 12/12/2022]
Abstract
Thiol-based redox compounds, namely thioredoxins (Trxs), glutaredoxins (Grxs) and peroxiredoxins (Prxs), stand as a pivotal group of proteins involved in antioxidant processes and redox signaling. Glutaredoxins (Grxs) are considered as one of the major families of proteins involved in redox regulation by removal of S-glutathionylation and thereby reactivation of other enzymes with thiol-dependent activity. Grxs are also coupled to Trxs and Prxs recycling and thereby indirectly contribute to reactive oxygen species (ROS) detoxification. Peroxiredoxins (Prxs) are a ubiquitous family of peroxidases, which play an essential role in the detoxification of hydrogen peroxide, aliphatic and aromatic hydroperoxides, and peroxynitrite. The Trxs, Grxs and Prxs systems, which reversibly induce thiol modifications, regulate redox signaling involved in various biological events in the cardiovascular system. This review focuses on the current knowledge of the role of Trxs, Grxs and Prxs on cardiovascular pathologies and especially in cardiac hypertrophy, ischemia/reperfusion (I/R) injury and heart failure as well as in the presence of cardiovascular risk factors, such as hypertension, hyperlipidemia, hyperglycemia and metabolic syndrome. Further studies on the roles of thiol-dependent redox systems in the cardiovascular system will support the development of novel protective and therapeutic strategies against cardiovascular diseases.
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Affiliation(s)
- Ioanna Andreadou
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Athens, Greece.
| | - Panagiotis Efentakis
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Athens, Greece
| | - Katie Frenis
- Department of Cardiology 1, Molecular Cardiology, University Medical Center of the Johannes Gutenberg University, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Andreas Daiber
- Department of Cardiology 1, Molecular Cardiology, University Medical Center of the Johannes Gutenberg University, Langenbeckstr. 1, 55131, Mainz, Germany.,Partner Site Rhine-Main, German Center for Cardiovascular Research (DZHK), Langenbeckstr 1, 55131, Mainz, Germany
| | - Rainer Schulz
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany.
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6
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van de Wetering C, Elko E, Berg M, Schiffers CHJ, Stylianidis V, van den Berge M, Nawijn MC, Wouters EFM, Janssen-Heininger YMW, Reynaert NL. Glutathione S-transferases and their implications in the lung diseases asthma and chronic obstructive pulmonary disease: Early life susceptibility? Redox Biol 2021; 43:101995. [PMID: 33979767 PMCID: PMC8131726 DOI: 10.1016/j.redox.2021.101995] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 01/01/2023] Open
Abstract
Our lungs are exposed daily to airborne pollutants, particulate matter, pathogens as well as lung allergens and irritants. Exposure to these substances can lead to inflammatory responses and may induce endogenous oxidant production, which can cause chronic inflammation, tissue damage and remodeling. Notably, the development of asthma and Chronic Obstructive Pulmonary Disease (COPD) is linked to the aforementioned irritants. Some inhaled foreign chemical compounds are rapidly absorbed and processed by phase I and II enzyme systems critical in the detoxification of xenobiotics including the glutathione-conjugating enzymes Glutathione S-transferases (GSTs). GSTs, and in particular genetic variants of GSTs that alter their activities, have been found to be implicated in the susceptibility to and progression of these lung diseases. Beyond their roles in phase II metabolism, evidence suggests that GSTs are also important mediators of normal lung growth. Therefore, the contribution of GSTs to the development of lung diseases in adults may already start in utero, and continues through infancy, childhood, and adult life. GSTs are also known to scavenge oxidants and affect signaling pathways by protein-protein interaction. Moreover, GSTs regulate reversible oxidative post-translational modifications of proteins, known as protein S-glutathionylation. Therefore, GSTs display an array of functions that impact the pathogenesis of asthma and COPD. In this review we will provide an overview of the specific functions of each class of mammalian cytosolic GSTs. This is followed by a comprehensive analysis of their expression profiles in the lung in healthy subjects, as well as alterations that have been described in (epithelial cells of) asthmatics and COPD patients. Particular emphasis is placed on the emerging evidence of the regulatory properties of GSTs beyond detoxification and their contribution to (un)healthy lungs throughout life. By providing a more thorough understanding, tailored therapeutic strategies can be designed to affect specific functions of particular GSTs.
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Affiliation(s)
- Cheryl van de Wetering
- Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands; Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, USA
| | - Evan Elko
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, USA
| | - Marijn Berg
- Pathology and Medical Biology, GRIAC Research Institute, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
| | - Caspar H J Schiffers
- Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands; Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, USA
| | - Vasili Stylianidis
- Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Maarten van den Berge
- Pulmonology, GRIAC Research Institute, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
| | - Martijn C Nawijn
- Pathology and Medical Biology, GRIAC Research Institute, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
| | - Emiel F M Wouters
- Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands; Ludwig Boltzmann Institute for Lung Health, Vienna, Austria
| | - Yvonne M W Janssen-Heininger
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, USA.
| | - Niki L Reynaert
- Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands.
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7
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Stroobants S, Van Molle I, Saidi Q, Jonckheere K, Maes D, Peeters E. Structure of the Prx6-subfamily 1-Cys peroxiredoxin from Sulfolobus islandicus. Acta Crystallogr F Struct Biol Commun 2019; 75:428-434. [PMID: 31204689 PMCID: PMC6572100 DOI: 10.1107/s2053230x19006472] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 05/07/2019] [Indexed: 11/28/2022] Open
Abstract
Aerobic thermoacidophilic archaea belonging to the genus Sulfolobus harbor peroxiredoxins, thiol-dependent peroxidases that assist in protecting the cells from oxidative damage. Here, the crystal structure of the 1-Cys peroxiredoxin from Sulfolobus islandicus, named 1-Cys SiPrx, is presented. A 2.75 Å resolution data set was collected from a crystal belonging to space group P212121, with unit-cell parameters a = 86.8, b = 159.1, c = 189.3 Å, α = β = γ = 90°. The structure was solved by molecular replacement using the homologous Aeropyrum pernix peroxiredoxin (ApPrx) structure as a search model. In the crystal structure, 1-Cys SiPrx assembles into a ring-shaped decamer composed of five homodimers. This quaternary structure corresponds to the oligomeric state of the protein in solution, as observed by size-exclusion chromatography. 1-Cys SiPrx harbors only a single cysteine, which is the peroxidatic cysteine, and lacks both of the cysteines that are highly conserved in the C-terminal arm domain in other archaeal Prx6-subfamily proteins such as ApPrx and that are involved in the association of dimers into higher-molecular-weight decamers and dodecamers. It is thus concluded that the Sulfolobus Prx6-subfamily protein undergoes decamerization independently of arm-domain cysteines.
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Affiliation(s)
- Sander Stroobants
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Inge Van Molle
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Queen Saidi
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Karl Jonckheere
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Dominique Maes
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Eveline Peeters
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
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8
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Abstract
Peroxiredoxins (Prxs) are a large and conserved family of peroxidases that are considered to be the primary cellular guardians against oxidative stress in all living organisms. Prxs share a thioredoxin fold and contain a highly-reactive peroxidatic cysteine in a specialised active-site environment that is able to reduce their peroxide substrates. The minimal functional unit for Prxs are either monomers or dimers, but many dimers assemble into decameric rings. Ring structures can further form a variety of high molecular weight complexes. Many eukaryotic Prxs contain a conserved GGLG and C-terminal YF motif that confer sensitivity to elevated levels of peroxide, leading to hyperoxidation and inactivation. Inactive forms of Prxs can be re-reduced by the enzyme sulfiredoxin, in an ATP-dependent reaction. Cycles of hyperoxidation and reactivation are considered to play an integral role in a variety of H2O2-mediated cell signalling pathways in both stress and non-stress conditions. Prxs are also considered to exhibit chaperone-like properties when cells are under oxidative or thermal stress. The roles of various types of covalent modifications, e.g. acetylation and phosphorylation are also discussed. The ability of Prxs to assemble into ordered arrays such as nanotubes is currently being exploited in nanotechnology.
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Affiliation(s)
- Zhenbo Cao
- Institute of Molecular, Cell and Systems Biology, Davidson Building, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
| | - John Gordon Lindsay
- Institute of Molecular, Cell and Systems Biology, Davidson Building, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK.
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Abstract
Disulfide bonds are important for the stability and function of many secreted proteins. In Gram-negative bacteria, these linkages are catalyzed by thiol-disulfide oxidoreductases (Dsb) in the periplasm. Protein oxidation has been well studied in these organisms, but it has not fully been explored in Gram-positive bacteria, which lack traditional periplasmic compartments. Recent bioinformatics analyses have suggested that the high-GC-content bacteria (i.e., actinobacteria) rely on disulfide-bond-forming pathways. In support of this, Dsb-like proteins have been identified in Mycobacterium tuberculosis, but their functions are not known. Actinomyces oris and Corynebacterium diphtheriae have recently emerged as models to study disulfide bond formation in actinobacteria. In both organisms, disulfide bonds are catalyzed by the membrane-bound oxidoreductase MdbA. Remarkably, unlike known Dsb proteins, MdbA is important for pathogenesis and growth, which makes it a potential target for new antibacterial drugs. This review will discuss disulfide-bond-forming pathways in bacteria, with a special focus on Gram-positive bacteria.
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Cho KJ, Park Y, Khan T, Lee JH, Kim S, Seok JH, Chung YB, Cho AE, Choi Y, Chang TS, Kim KH. Crystal Structure of Dimeric Human Peroxiredoxin-1 C83S Mutant. B KOREAN CHEM SOC 2015. [DOI: 10.1002/bkcs.10284] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Ki Joon Cho
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - YiHo Park
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - Taslima Khan
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - Ji-Hye Lee
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - Sella Kim
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - Jong Hyeon Seok
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - Yeon Bin Chung
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - Art E. Cho
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
| | - Yongseok Choi
- Department of Life Sciences; Korea University; Seoul 136-701 Korea
| | - Tong-Shin Chang
- Department of Pharmacology; Ewha Women's University; Seoul 121-742 Korea
| | - Kyung Hyun Kim
- Department of Biotechnology & Bioinformatics; Korea University; Sejong 339-700 Korea
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van Zwieten R, Verhoeven AJ, Roos D. Inborn defects in the antioxidant systems of human red blood cells. Free Radic Biol Med 2014; 67:377-86. [PMID: 24316370 DOI: 10.1016/j.freeradbiomed.2013.11.022] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 11/20/2013] [Accepted: 11/22/2013] [Indexed: 12/25/2022]
Abstract
Red blood cells (RBCs) contain large amounts of iron and operate in highly oxygenated tissues. As a result, these cells encounter a continuous oxidative stress. Protective mechanisms against oxidation include prevention of formation of reactive oxygen species (ROS), scavenging of various forms of ROS, and repair of oxidized cellular contents. In general, a partial defect in any of these systems can harm RBCs and promote senescence, but is without chronic hemolytic complaints. In this review we summarize the often rare inborn defects that interfere with the various protective mechanisms present in RBCs. NADPH is the main source of reduction equivalents in RBCs, used by most of the protective systems. When NADPH becomes limiting, red cells are prone to being damaged. In many of the severe RBC enzyme deficiencies, a lack of protective enzyme activity is frustrating erythropoiesis or is not restricted to RBCs. Common hereditary RBC disorders, such as thalassemia, sickle-cell trait, and unstable hemoglobins, give rise to increased oxidative stress caused by free heme and iron generated from hemoglobin. The beneficial effect of thalassemia minor, sickle-cell trait, and glucose-6-phosphate dehydrogenase deficiency on survival of malaria infection may well be due to the shared feature of enhanced oxidative stress. This may inhibit parasite growth, enhance uptake of infected RBCs by spleen macrophages, and/or cause less cytoadherence of the infected cells to capillary endothelium.
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Affiliation(s)
- Rob van Zwieten
- Laboratory of Red Blood Cell Diagnostics, Department of Blood Cell Research, Sanquin Blood Supply Organization, 1066 CX Amsterdam, The Netherlands.
| | - Arthur J Verhoeven
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Dirk Roos
- Laboratory of Red Blood Cell Diagnostics, Department of Blood Cell Research, Sanquin Blood Supply Organization, 1066 CX Amsterdam, The Netherlands
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12
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Luesken FA, Wu ML, Op den Camp HJM, Keltjens JT, Stunnenberg H, Francoijs KJ, Strous M, Jetten MSM. Effect of oxygen on the anaerobic methanotroph 'Candidatus Methylomirabilis oxyfera': kinetic and transcriptional analysis. Environ Microbiol 2012; 14:1024-34. [PMID: 22221911 DOI: 10.1111/j.1462-2920.2011.02682.x] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
'Candidatus Methylomirabilis oxyfera' is a denitrifying methanotroph that performs nitrite-dependent anaerobic methane oxidation through a newly discovered intra-aerobic pathway. In this study, we investigated the response of a M. oxyfera enrichment culture to oxygen. Addition of either 2% or 8% oxygen resulted in an instant decrease of methane and nitrite conversion rates. Oxygen exposure also led to a deviation in the nitrite to methane oxidation stoichiometry. Oxygen-uptake and inhibition studies with cell-free extracts displayed a change from cytochrome c to quinol as electron donor after exposure to oxygen. The change in global gene expression was monitored by deep sequencing of cDNA using Illumina technology. After 24 h of oxygen exposure, transcription levels of 1109 (out of 2303) genes changed significantly when compared with the anoxic period. Most of the genes encoding enzymes of the methane oxidation pathway were constitutively expressed. Genes from the denitrification pathway, with exception of one of the putative nitric oxide reductases, norZ2, were severely downregulated. The majority of known genes involved in the vital cellular functions, such as nucleic acid and protein biosynthesis and cell division processes, were downregulated. The alkyl hydroperoxide reductase, ahpC, and genes involved in the synthesis/repair of the iron-sulfur clusters were among the few upregulated genes. Further, transcription of the pmoCAB genes of aerobic methanotrophs present in the non-M. oxyfera community were triggered by the presence of oxygen. Our results show that oxygen-exposed cells of M. oxyfera were under oxidative stress and that in spite of its oxygenic capacity, exposure to microoxic conditions has an overall detrimental effect.
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Affiliation(s)
- Francisca A Luesken
- Department of Microbiology, Radboud University Nijmegen, Institute for Water and Wetland Research, Nijmegen, The Netherlands
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13
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Tew KD, Manevich Y, Grek C, Xiong Y, Uys J, Townsend DM. The role of glutathione S-transferase P in signaling pathways and S-glutathionylation in cancer. Free Radic Biol Med 2011; 51:299-313. [PMID: 21558000 PMCID: PMC3125017 DOI: 10.1016/j.freeradbiomed.2011.04.013] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 04/07/2011] [Accepted: 04/07/2011] [Indexed: 12/12/2022]
Abstract
Glutathione S-transferase P is abundantly expressed in some mammalian tissues, particularly those associated with malignancies. While the enzyme can catalyze thioether bond formation between some electrophilic chemicals and GSH, novel nondetoxification functions are now ascribed to it. This review summarizes recent material that implicates GSTP in mediating S-glutathionylation of specific clusters of target proteins and in reactions that define a negative regulatory role in some kinase pathways through ligand or protein:protein interactions. It is becoming apparent that GSTP participates in the maintenance of cellular redox homeostasis through a number of convergent and divergent mechanisms. Moreover, drug platforms that have GSTP as a target have produced some interesting preclinical and clinical candidates.
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Affiliation(s)
- Kenneth D Tew
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Avenue, Charleston, SC 29425, USA.
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14
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Meng EC, Babbitt PC. Topological variation in the evolution of new reactions in functionally diverse enzyme superfamilies. Curr Opin Struct Biol 2011; 21:391-7. [PMID: 21458983 PMCID: PMC3551608 DOI: 10.1016/j.sbi.2011.03.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 03/05/2011] [Accepted: 03/09/2011] [Indexed: 10/18/2022]
Abstract
In functionally diverse enzyme superfamilies (SFs), conserved structural and active site features reflect catalytic capabilities 'hard-wired' in each SF architecture. Overlaid on this foundation, evolutionary changes in active site machinery, structural topology and other aspects of structural organization and interactions support the emergence of new reactions, mechanisms, and substrate specificity. This review connects topological with functional variation in each of the haloalkanoic acid dehalogenase (HAD) and vicinal oxygen chelate fold (VOC) SFs and a set of redox-active thioredoxin (Trx)-fold SFs to illustrate a few of the varied themes nature has used to evolve new functions from a limited set of structural scaffolds.
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Affiliation(s)
- Elaine C. Meng
- Department of Pharmaceutical Chemistry, University of California, M/S 2240, 600 16th Street, San Francisco, CA 94158-2517, USA,
| | - Patricia C. Babbitt
- Department of Pharmaceutical Chemistry, University of California, M/S 2240, 600 16th Street, San Francisco, CA 94158-2517, USA,
- Department of Bioengineering and Therapeutic Sciences, University of California, M/S 2250, 1700 4 Street, San Francisco, CA 94158-2330, USA
- California Institute for Quantitative Biosciences, University of California, San Francisco
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15
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Qu W, Zhou Y, Sun Y, Fang M, Yu H, Li W, Liu Z, Zeng J, Chen C, Gao C, Jia J. Identification of S-nitrosylation of proteins of Helicobacter pylori in response to nitric oxide stress. J Microbiol 2011; 49:251-6. [PMID: 21538246 DOI: 10.1007/s12275-011-0262-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 11/10/2010] [Indexed: 12/16/2022]
Abstract
Innate and adaptive immune responses are activated in humans when Helicobacter pylori invades the gastric mucosa. Nitric oxide (NO) and reactive nitrogen species are important immune effectors, which can exert their functions through oxidation and S-nitrosylation of proteins. S-nitrosoglutathione and sodium nitroprus-side were used as NO donors and H. pylori cells were incubated with these compounds to analyze the inhibitory effect of NO. The suppressing effect of NO on H. pylori has been shown in vitro. Furthermore, the proteins modified by S-nitrosylation in H. pylori were identified through the biotin switch method in association with matrix-assisted laser desorption ionization/time-of-flight tandem mass spectrometry (MALDI-TOF-MS/MS). Five S-nitrosylated proteins identified were a chaperone and heat-shock protein (GroEL), alkyl hydroperoxide reductase (TsaA), urease alpha subunit (UreA), HP0721, and HP0129. Importantly, S-nitrosylation of TsaA and UreA were confirmed using purified recombinant proteins. Considering the importance of these enzymes in antioxidant defenses, adherence, and colonization, NO may exert its antibacterial actions by targeting enzymes through S-nitrosylation. Identification of protein S-nitrosylation may contribute to an understanding of the antibacterial actions of NO. Our findings provide an insight into potential targets for the development of novel therapeutic agents against H. pylori infection.
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Affiliation(s)
- Wei Qu
- Department of Microbiology and Immunology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, P R China
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16
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Schultz-Norton JR, Ziegler YS, Nardulli AM. ERα-associated protein networks. Trends Endocrinol Metab 2011; 22:124-9. [PMID: 21371903 DOI: 10.1016/j.tem.2010.11.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2010] [Revised: 11/30/2010] [Accepted: 11/30/2010] [Indexed: 11/21/2022]
Abstract
Estrogen receptor α (ERα) is a ligand-activated transcription factor that, upon binding hormone, interacts with specific recognition sequences in DNA. An extensive body of literature has documented the association of individual regulatory proteins with ERα. It has recently become apparent that, instead of simply recruiting individual proteins, ERα recruits interconnected networks of proteins with discrete activities that play crucial roles in maintaining the structure and function of the receptor, stabilizing the receptor-DNA interaction, influencing estrogen-responsive gene expression, and repairing misfolded proteins and damaged DNA. Together these studies suggest that the DNA-bound ERα serves as a nucleating factor for the recruitment of protein complexes involved in key processes including the oxidative stress response, DNA repair, and transcription regulation.
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Affiliation(s)
- Jennifer R Schultz-Norton
- Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 407 South Goodwin Avenue, Urbana, IL 61801, USA
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17
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Pourakbari B, Mirsalehian A, Maleknejad P, Mamishi S, Azhdarkosh H, Daryani NE, Najafi M, Kazemi B, Paknejad M, Mahmoudi S, Bandehpour M, Ghazi M, Salavati A. Evaluation of a new antigen for diagnosis of Helicobacter pylori infection in stool of adult and children. Helicobacter 2011; 16:42-6. [PMID: 21241411 DOI: 10.1111/j.1523-5378.2010.00813.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Nowadays, there is an increasing interest in noninvasive methods to diagnose Helicobacter pylori infection. Indeed, they can profitably replace endoscopy in predicting the diagnosis. The stool antigen test for H. pylori is a noninvasive immunoassay to diagnose active infection with this bacterium in human fecal samples. The aim of this study was detection of alkyl hydroperoxide reductase protein (AhpC) antigen by immunoblotting in stool samples for diagnosis of H. pylori. MATERIALS AND METHODS Chromosomal DNA from H. pylori was isolated. AhpC gene was amplified by PCR, These amplicons were cloned into pTZ57R/T cloning vector then subcloned into pQE30 expression vector and overexpressed using isopropyl-beta-D-thiogalactopyranoside in E. coli M15. AhpC protein was purified by affinity chromatography. Rabbits were immunized with the purified AhpC protein for the production of antibodies. To determine the accuracy of the test for diagnosing H. pylori infection from stool, we evaluated 84 patients (6-81 years old) using Western blot analysis by rabbit anti-AhpC antibody. Positive rapid urease test on biopsy samples was considered as the gold standard. RESULTS AhpC gene was overexpressed, and AhpC protein was purified. Rabbit anti-AhpC antibody produced after immunization with the purified AhpC protein. By immunoblotting, we detected AhpC protein in the positive stool samples. The test showed a 83.3% sensitivity (95% CI: 69.8-92.5%) and a 91.7% specificity (95% CI: 77.5-98.2). Among the children, the sensitivity was 88.2% (95% CI: 63.6-98.5) and the specificity was 100% (95% CI: 69.2-100); in adults, the sensitivity and specificity were 80.6% (95% CI: 62.5-92.5) and 88.5% (95% CI: 69.8-97.6), respectively. CONCLUSIONS Using of AhpC antigen for diagnosis of H. pylori infection is a useful noninvasive method, accurate in adolescents and children, and can be used for the development of a stool antigen detection kit for H. pylori.
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Affiliation(s)
- Babak Pourakbari
- Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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18
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Actinobacterial peroxidases: an unexplored resource for biocatalysis. Appl Biochem Biotechnol 2011; 164:681-713. [PMID: 21279698 DOI: 10.1007/s12010-011-9167-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 01/10/2011] [Indexed: 10/18/2022]
Abstract
Peroxidases are redox enzymes that can be found in all forms of life where they play diverse roles. It is therefore not surprising that they can also be applied in a wide range of industrial applications. Peroxidases have been extensively studied with particular emphasis on those isolated from fungi and plants. In general, peroxidases can be grouped into haem-containing and non-haem-containing peroxidases, each containing protein families that share sequence similarity. The order Actinomycetales comprises a large group of bacteria that are often exploited for their diverse metabolic capabilities, and with recent increases in the number of sequenced genomes, it has become clear that this metabolically diverse group of organisms also represents a large resource for redox enzymes. It is therefore surprising that, to date, no review article has been written on the wide range of peroxidases found within the actinobacteria. In this review article, we focus on the different types of peroxidases found in actinobacteria, their natural role in these organisms and how they compare with the more well-described peroxidases. Finally, we also focus on work remaining to be done in this research field in order for peroxidases from actinobacteria to be applied in industrial processes.
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19
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Matin MN, Saief SA, Rahman MM, Lee DH, Kang H, Lee DS, Kang SG. Comparative phenotypic and physiological characteristics of spotted leaf 6 (spl6) and brown leaf spot2 (bl2) lesion mimic mutants (LMM) in rice. Mol Cells 2010; 30:533-43. [PMID: 21110131 DOI: 10.1007/s10059-010-0151-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Revised: 08/15/2010] [Accepted: 09/13/2010] [Indexed: 10/18/2022] Open
Abstract
Spontaneous necrotic lesions were found in a lesion mimic mutant brown leaf spot 2 (bl2) without pathogenic infection. Small spots in the seedlings appeared at the four leaves stage and gradually grew into a large round and black area with a gray center on the leaf surfaces. Lower growth habit and lower agronomic trait values with reduced stature, tiller, and panicle number, as well as lower yield potential were noted in the mutants relative to the trait values of the wild-type plants. Microscopic analysis revealed that mesophyll chloroplast was severely damaged or absent in the spotted area of the mutant leaves. Total chlorophyll content, hydrogen peroxide level, and catalase activity were increased at up to 45 days after germination and were dropped at 60 d in the mutant leaves. However, the total protein contents were reduced slightly with a growth period of up to 45 days and were increased at 60 days after germination. A gradual increment of the total ascorbic acid contents in the mutants were observed with advanced plant age, but increased until 45 days and dropped comparatively at 60 days in the wild-type leaves. Increased gene transcriptions of OsPDI and OsGPX1 were noted in the spotted leaves as compared to the non-spotted leaves of the mutant and wild-type leaves, whereas transcripts of OsTPX were transcribed at lower levels in the spotted leaves as compared to the non-spotted leaves. The genetic nature of the bl2 mutant indicated that the F(1) plants evidenced the wild-type phenotype and that bl2 was governed by a single recessive gene.
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Affiliation(s)
- Mohammad Nurul Matin
- Molecular Genetics Laboratory, School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea
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20
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Umate P. Genome-wide analysis of thioredoxin fold superfamily peroxiredoxins in Arabidopsis and rice. PLANT SIGNALING & BEHAVIOR 2010; 5:1543-6. [PMID: 21242720 PMCID: PMC3115098 DOI: 10.4161/psb.5.12.13494] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A broad range of peroxides generated in subcellular compartments, including chloroplasts, are detoxified with peroxidases which are called as peroxiredoxins (Prx). The Prx are ubiquitously distributed in all organisms including bacteria, fungi, animals, and also in cyanobacteria and plants. Recently, the Prx have emerged as new molecules in antioxidant defense in plants. Here, the members which belong to Prx gene family in Arabidopsis and rice are been identified. Overall, the Prx members constitute a small family with 10 and 11 genes in Arabidopsis and rice respectively. The prx genes of rice are assigned to their functional groups based on homology search against Arabidopsis protein database. Deciphering the Prx functions in rice will add novel information to the mechanism of antioxidant defense in plants. Further, the Prx also forms the part of redox signaling cascade. Here, the Prx family has been described for rice.
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Affiliation(s)
- Pavan Umate
- Department of Botany, Kakatiya University, Warangal, India.
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21
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Strand KR, Sun C, Li T, Jenney FE, Schut GJ, Adams MWW. Oxidative stress protection and the repair response to hydrogen peroxide in the hyperthermophilic archaeon Pyrococcus furiosus and in related species. Arch Microbiol 2010; 192:447-59. [PMID: 20379702 DOI: 10.1007/s00203-010-0570-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 03/23/2010] [Accepted: 03/25/2010] [Indexed: 11/26/2022]
Abstract
Pyrococcus furiosus is a shallow marine, anaerobic archaeon that grows optimally at 100 degrees C. Addition of H(2)O(2) (0.5 mM) to a growing culture resulted in the cessation of growth with a 2-h lag before normal growth resumed. Whole genome transcriptional profiling revealed that the main response occurs within 30 min of peroxide addition, with the up-regulation of 62 open reading frames (ORFs), 36 of which are part of 10 potential operons. More than half of the up-regulated ORFs are of unknown function, while some others encode proteins that are involved potentially in sequestering iron and sulfide, in DNA repair and in generating NADPH. This response is thought to involve primarily damage repair rather than protection, since cultures exposed to sub-toxic levels of H(2)O(2) were not more resistant to the subsequent addition of H(2)O(2) (0.5-5.0 mM). Consequently, there is little if any induced protective response to peroxide. The organism maintains a constitutive protective mechanism involving high levels of oxidoreductase-type enzymes such as superoxide reductase, rubrerythrin, and alkyl hydroperoxide reductase. Related hyperthermophiles contain homologs of the proteins involved in the constitutive protective mechanism but these organisms were more sensitive to peroxide than P. furiosus and lack several of its peroxide-responsive ORFs.
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Affiliation(s)
- Kari R Strand
- Department of Biochemistry and Molecular Biology, University of Georgia, Life Sciences Bldg., Athens, GA 30602-7229, USA
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22
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Lukosz M, Jakob S, Büchner N, Zschauer TC, Altschmied J, Haendeler J. Nuclear redox signaling. Antioxid Redox Signal 2010; 12:713-42. [PMID: 19737086 DOI: 10.1089/ars.2009.2609] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Reactive oxygen species have been described to modulate proteins within the cell, a process called redox regulation. However, the importance of compartment-specific redox regulation has been neglected for a long time. In the early 1980s and 1990s, many in vitro studies introduced the possibility that nuclear redox signaling exists. However, the functional relevance for that has been greatly disregarded. Recently, it has become evident that nuclear redox signaling is indeed one important signaling mechanism regulating a variety of cellular functions. Transcription factors, and even kinases and phosphatases, have been described to be redox regulated in the nucleus. This review describes several of these proteins in closer detail and explains their functions resulting from nuclear localization and redox regulation. Moreover, the redox state of the nucleus and several important nuclear redox regulators [Thioredoxin-1 (Trx-1), Glutaredoxins (Grxs), Peroxiredoxins (Prxs), and APEX nuclease (multifunctional DNA-repair enzyme) 1 (APEX1)] are introduced more precisely, and their necessity for regulation of transcription factors is emphasized.
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Affiliation(s)
- Margarete Lukosz
- Molecular Cell & Aging Research, IUF (Institute for Molecular Preventive Medicine), At the University of Duesseldorf gGmbH, Auf'm Hennekamp 50, 40225 Duesseldorf, Germany
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23
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Ora A, Oksanen E, Kajander T, Goldman A, Butcher SJ. Crystallization and preliminary crystallographic analysis of mouse peroxiredoxin II with significant pseudosymmetry. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:357-60. [PMID: 20208180 DOI: 10.1107/s1744309110003684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Accepted: 01/29/2010] [Indexed: 11/10/2022]
Abstract
Peroxiredoxin II was cloned from mouse B cells into pCold 1 expression vector and produced as a His-tagged recombinant protein in Escherichia coli. A ring form was isolated by gel filtration. A crystal obtained by the sitting-drop vapour-diffusion method diffracted to 1.77 A resolution at 100 K. The crystal belonged to space group P2(1)2(1)2, with unit-cell parameters a = 117.4, b = 133.9, c = 139.1 A. The asymmetric unit is expected to contain six dimers of peroxiredoxin II, with a corresponding solvent content of 39.3%. Peaks in the native Patterson function together with pseudo-systematic absences suggested that the crystals suffered from severe translational pseudosymmetry.
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Affiliation(s)
- Ari Ora
- Institute of Biotechnology, PO Box 65, 00014 University of Helsinki, Finland
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24
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An extracellular disulfide bond forming protein (DsbF) from Mycobacterium tuberculosis: structural, biochemical, and gene expression analysis. J Mol Biol 2010; 396:1211-26. [PMID: 20060836 DOI: 10.1016/j.jmb.2009.12.060] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 12/03/2009] [Accepted: 12/29/2009] [Indexed: 12/21/2022]
Abstract
Disulfide bond forming (Dsb) proteins ensure correct folding and disulfide bond formation of secreted proteins. Previously, we showed that Mycobacterium tuberculosis DsbE (Mtb DsbE, Rv2878c) aids in vitro oxidative folding of proteins. Here, we present structural, biochemical, and gene expression analyses of another putative Mtb secreted disulfide bond isomerase protein homologous to Mtb DsbE, Mtb DsbF (Rv1677). The X-ray crystal structure of Mtb DsbF reveals a conserved thioredoxin fold although the active-site cysteines may be modeled in both oxidized and reduced forms, in contrast to the solely reduced form in Mtb DsbE. Furthermore, the shorter loop region in Mtb DsbF results in a more solvent-exposed active site. Biochemical analyses show that, similar to Mtb DsbE, Mtb DsbF can oxidatively refold reduced, unfolded hirudin and has a comparable pK(a) for the active-site solvent-exposed cysteine. However, contrary to Mtb DsbE, the Mtb DsbF redox potential is more oxidizing and its reduced state is more stable. From computational genomics analysis of the M. tuberculosis genome, we identified a potential Mtb DsbF interaction partner, Rv1676, a predicted peroxiredoxin. Complex formation is supported by protein coexpression studies and inferred by gene expression profiles, whereby Mtb DsbF and Rv1676 are upregulated under similar environments. Additionally, comparison of Mtb DsbF and Mtb DsbE gene expression data indicates anticorrelated gene expression patterns, suggesting that these two proteins and their functionally linked partners constitute analogous pathways that may function under different conditions.
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The Role of Peroxiredoxins in Oxygenic Photosynthesis of Cyanobacteria and Higher Plants: Peroxide Detoxification or Redox Sensing? PHOTOPROTECTION, PHOTOINHIBITION, GENE REGULATION, AND ENVIRONMENT 2008. [DOI: 10.1007/1-4020-3579-9_19] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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26
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Substrate specificity and redox potential of AhpC, a bacterial peroxiredoxin. Proc Natl Acad Sci U S A 2007; 105:8209-14. [PMID: 18165315 DOI: 10.1073/pnas.0708308105] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Typical 2-Cys peroxiredoxins (Prxs) are ubiquitous peroxidases that are involved in peroxide scavenging and/or the regulation of peroxide signaling in eukaryotes. Despite their prevalence, very few Prxs have been reliably characterized in terms of their substrate specificity profile and redox potential even though these values are important for gaining insight into physiological function. Here, we present such studies focusing on Salmonella typhimurium alkyl hydroperoxide reductase C component (StAhpC), an enzyme that has proven to be an excellent prototype of this largest and most widespread class of Prxs that includes mammalian Prx I-Prx IV. The catalytic efficiencies of StAhpC (k(cat)/K(m)) are >10(7) M(-1).s(-1) for inorganic and primary hydroperoxide substrates and approximately 100-fold less for tertiary hydroperoxides, with the difference being exclusively caused by changes in K(m). The oxidative inactivation of AhpC through reaction with a second molecule of peroxide shows parallel substrate specificity. The midpoint reduction potential of StAhpC is determined to be -178 +/- 0.4 mV, a value much higher than most other thiol-based redox proteins. The relevance of these results for our understanding of Prx and the physiological role of StAhpC is discussed.
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27
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Kang SG, Matin MN, Bae H, Natarajan S. Proteome analysis and characterization of phenotypes of lesion mimic mutant spotted leaf 6 in rice. Proteomics 2007; 7:2447-58. [PMID: 17623303 DOI: 10.1002/pmic.200600961] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Rice spotted leaf 6 (spl6) mutant produces lesions caused by spontaneous cell death in the absence of pathogenic infection. Expression of this genetic trait was developmentally programmed. After the tillering stage, small red and brown lesions were initiated in groups on the leaf blade. Eventually, the lesions formed parallel lines along the midrib of the leaf. Under light and transmission electron microscopy, we observed that thylakoid membranes of mesophyll chloroplasts were progressively damaged in the nonspotted section of the mutant leaf. However, chloroplasts were absent in the mesophyll cells of the spotted area of the spl6 mutant. These results indicated that lesion formation of the spl6 mutant might be caused by oxidative burst. Proteome analysis revealed that 159 protein spots were up or downregulated in comparison between spotted leaves of the spl6 mutant plants and normal leaves of the wild type. Among them, protein disulfide isomerase (PDI), transketolase, thioredoxin peroxidase (TPX), ATP synthase, RuBisCO large subunit, and RuBisCO activase small subunit were not identified in the spl6 mutant but were abundant in the wild type. Especially, the absence of TPX and PDI might be the cause of the failure to protect cells against oxidative burst resulting in degradation of the thylakoid membranes and leading to programmed cell death and lesion development.
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Affiliation(s)
- Sang Gu Kang
- Molecular Genetics Laboratory, School of Biotechnology, Institute of Biotechnology, Yeungnam University, Gyeongsan, Korea.
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28
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Abstract
Glutathione peroxidases (GPXs, EC 1.11.1.9) were first discovered in mammals as key enzymes involved in scavenging of activated oxygen species (AOS). Their efficient antioxidant activity depends on the presence of the rare amino-acid residue selenocysteine (SeCys) at the catalytic site. Nonselenium GPX-like proteins (NS-GPXs) with a Cys residue instead of SeCys have also been found in most organisms. As SeCys is important for GPX activity, the function of the NS-GPX can be questioned. Here, we highlight the evolutionary link between NS-GPX and seleno-GPX, particularly the evolution of the SeCys incorporation system. We then discuss what is known about the enzymatic activity and physiological functions of NS-GPX. Biochemical studies have shown that NS-GPXs are not true GPXs; notably they reduce AOS using reducing substrates other than glutathione, such as thioredoxin. We provide evidence that, in addition to their inefficient scavenging action, NS-GPXs act as AOS sensors in various signal-transduction pathways.
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29
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van der Klei IJ, Yurimoto H, Sakai Y, Veenhuis M. The significance of peroxisomes in methanol metabolism in methylotrophic yeast. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:1453-62. [PMID: 17023065 DOI: 10.1016/j.bbamcr.2006.07.016] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2006] [Accepted: 07/26/2006] [Indexed: 11/22/2022]
Abstract
The capacity to use methanol as sole source of carbon and energy is restricted to relatively few yeast species. This may be related to the low efficiency of methanol metabolism in yeast, relative to that of prokaryotes. This contribution describes the details of methanol metabolism in yeast and focuses on the significance of compartmentalization of this metabolic pathway in peroxisomes.
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Affiliation(s)
- Ida J van der Klei
- Eukaryotic Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, P.O. Box 14, NL-9750 AA Haren, The Netherlands
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Noguera-Mazon V, Krimm I, Walker O, Lancelin JM. Protein-protein interactions within peroxiredoxin systems. PHOTOSYNTHESIS RESEARCH 2006; 89:277-90. [PMID: 17089212 DOI: 10.1007/s11120-006-9106-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Accepted: 09/11/2006] [Indexed: 05/12/2023]
Abstract
Peroxiredoxin systems in plants were demonstrated involved in crucial roles related to reactive oxygenated species (ROS) metabolism and the linked cell signalling to ROS. Peroxiredoxins function as peroxidasic systems that combine at least a reactivating reductant agent like thioredoxins, and sometimes glutaredoxins and glutathion. In the past three years a number of peroxiredoxin structures were solved by crystallography in different experimental crystallisation conditions. The structures have revealed a significant propensity of peroxiredoxins for oligomerism that was confirmed by biophysical studies in solution using NMR and other methods as analytical ultra-centrifugation. These studies showed that quaternary structures of peroxiredoxins involve specific protein-protein interaction interfaces that rely upon the peroxiredoxin types and/or their redox conditions. The protein-protein interactions with the reactivating redoxins essentially lead to transient unstable complexes. We review herein the different protein-protein interactions characterized or deduced from those reports.
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Affiliation(s)
- Valérie Noguera-Mazon
- Sciences Analytiques, ANABIO - RMN et Spectrométrie de Masse Biomoléculaires, CNRS UMR 5180, Université Claude Bernard - Lyon 1, Domaine Scientifique de La Doua, Ecole Supérieure de Chimie Physique Electronique de Lyon, F-69622, Villeurbanne, France
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31
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Abstract
The production of reactive oxygen species (ROS) accompanies many signaling events. Antioxidants and ROS scavenging enzymes in general have effects that indicate a critical role for ROS in downstream signaling, but a mechanistic understanding of the contribution of ROS as second messengers is incomplete. Here, the role of reactive oxygen species in cell signaling is discussed, emphasizing the ability of ROS to directly modify signaling proteins through thiol oxidation. Examples are provided of protein thiol modifications that control signal transduction effectors that include protein kinases, phosphatases, and transcription factors. Whereas the effects of cysteine oxidation on these proteins in experimental systems is clear, it has proven more difficult to demonstrate these modifications in response to physiologic stimuli. Improved detection methods for analysis of thiol modification will be essential to define these regulatory mechanisms. Bridging these two areas of research could reveal new regulatory mechanisms in signaling pathways, and identify new therapeutic targets.
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Affiliation(s)
- Janet V Cross
- Department of Pathology, University of Virginia, Charlottesville, 22908, USA
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32
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Ohara N, Kikuchi Y, Shoji M, Naito M, Nakayama K. Superoxide dismutase-encoding gene of the obligate anaerobe Porphyromonas gingivalis is regulated by the redox-sensing transcription activator OxyR. MICROBIOLOGY-SGM 2006; 152:955-966. [PMID: 16549660 DOI: 10.1099/mic.0.28537-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Inspection of the genomic DNA sequence of the oral anaerobe Porphyromonas gingivalis reveals that the micro-organism possesses the peroxide-sensing transcription activator OxyR, but not the superoxide-sensing transcription factor SoxR. Investigatation of oxidative-stress-responsive proteins in P. gingivalis by two-dimensional gel electrophoresis showed that two proteins were predominantly upregulated in oxidative conditions. In a P. gingivalis oxyR mutant these two proteins were not induced by treatment with hydrogen peroxide under aerobic conditions. By N-terminal amino acid sequencing, the two proteins were found to be superoxide dismutase and alkyl hydroperoxide reductase, encoded by sod and ahpC, respectively. Northern blot and lacZ fusion analyses revealed that P. gingivalis sod and ahpC were positively regulated by OxyR. Primer extension analysis located the promoter regions of sod and ahpC, and putative -35 boxes of these promoters were found immediately adjacent to their putative OxyR-binding sequences. Moreover, the promoter regions of sod and ahpC had the ability to bind P. gingivalis OxyR protein. These results demonstrate that P. gingivalis sod is one of the OxyR regulons, suggesting that OxyR functions as an intracellular redox sensor rather than a peroxide sensor in this organism. A sod gene of Bacteroides fragilis, which is taxonomically related to P. gingivalis, is inducible by redox stresses but not controlled by its OxyR. A DNA fragment including the B. fragilis sod promoter region could bind the P. gingivalis OxyR protein; however, a putative OxyR binding sequence within the DNA fragment was 14 bases distant from a putative -35 box of its promoter.
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MESH Headings
- Adaptation, Physiological/genetics
- Artificial Gene Fusion
- Bacterial Proteins/analysis
- Base Sequence
- Blotting, Northern
- DNA, Bacterial
- Electrophoresis, Gel, Two-Dimensional
- Electrophoretic Mobility Shift Assay
- Gene Expression Regulation, Bacterial
- Genes, Reporter
- Hydrogen Peroxide/pharmacology
- Molecular Sequence Data
- Mutation
- Oxidants/pharmacology
- Oxidation-Reduction
- Oxidative Stress
- Peroxidases/biosynthesis
- Peroxidases/genetics
- Peroxiredoxins
- Porphyromonas gingivalis/enzymology
- Porphyromonas gingivalis/genetics
- Promoter Regions, Genetic
- Protein Binding
- RNA, Bacterial/analysis
- RNA, Messenger/analysis
- Superoxide Dismutase/biosynthesis
- Superoxide Dismutase/genetics
- Trans-Activators/physiology
- Transcription, Genetic
- beta-Galactosidase/analysis
- beta-Galactosidase/genetics
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Affiliation(s)
- Naoya Ohara
- Division of Microbiology and Oral Infection, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Yuichiro Kikuchi
- Division of Microbiology and Oral Infection, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Mikio Shoji
- Division of Microbiology and Oral Infection, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Mariko Naito
- Division of Microbiology and Oral Infection, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Koji Nakayama
- Division of Microbiology and Oral Infection, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
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33
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Di Pietro R, Fang H, Fields K, Miller S, Flora M, Petricoin EC, Dveksler G, Rana RA, Grimley PM. Peroxiredoxin genes are not induced in myeloid leukemia cells exposed to ionizing radiation. Int J Immunopathol Pharmacol 2006; 19:517-24. [PMID: 17026836 DOI: 10.1177/039463200601900307] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Peroxiredoxins (Prx) comprise an extended family of small antioxidant proteins which conserve a thioredoxin-dependent catalytic function that can contribute to cell protection from reactive oxygen species (ROS). ROS generation is one of the deleterious intracellular effects of ionizing radiation, but the role of Prx during radiation treatment has not been extensively explored. Present experiments measure effects of ionizing radiation on expression of human Prx types I (PAGA), II (NKEF-B) and IV (AOE372) in human myeloid leukemia cells (K562). Prx gene transcription was analyzed by amplifying with RT-PCR cDNAs complementary to each Prx-specific coding sequence and by identifying the derived products with Southern blotting procedure. Transcripts of GAPDH were used as the endogenous standard for semi-quantitative comparisons. No consistent increase in Prx gene expression was detected at time intervals up to 72 h after gamma radiation doses that caused cell cycle arrest and nuclear damage (maximum 20 Gy). Immunoblots also were consistent with a prolonged expression or stability of the Prx I/II proteins. Similarly, a cytotoxic concentration of the oxidant hemin, which stimulates rapid hemoglobinization of K562 cells, caused no induction of Prx gene expression. Our results indicate a high Prx stability in human radio-resistant leukemia cells.
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Affiliation(s)
- R Di Pietro
- Department of Biomorphology, G. d'Annunzio University, Chieti-Pescara, Italy.
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34
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Nakamura T, Yamamoto T, Inoue T, Matsumura H, Kobayashi A, Hagihara Y, Uegaki K, Ataka M, Kai Y, Ishikawa K. Crystal structure of thioredoxin peroxidase from aerobic hyperthermophilic archaeon Aeropyrum pernix K1. Proteins 2006; 62:822-6. [PMID: 16342268 DOI: 10.1002/prot.20796] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Tsutomu Nakamura
- National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka, Japan.
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35
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Oxidative Stress-dependent Structural and Functional Regulation of 2-cysteine Peroxiredoxins In Eukaryotes Including Plant Cells. ACTA ACUST UNITED AC 2006. [DOI: 10.5010/jpb.2006.33.1.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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36
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Solaini G, Harris D. Biochemical dysfunction in heart mitochondria exposed to ischaemia and reperfusion. Biochem J 2006; 390:377-94. [PMID: 16108756 PMCID: PMC1198918 DOI: 10.1042/bj20042006] [Citation(s) in RCA: 157] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Heart tissue is remarkably sensitive to oxygen deprivation. Although heart cells, like those of most tissues, rapidly adapt to anoxic conditions, relatively short periods of ischaemia and subsequent reperfusion lead to extensive tissue death during cardiac infarction. Heart tissue is not readily regenerated, and permanent heart damage is the result. Although mitochondria maintain normal heart function by providing virtually all of the heart's ATP, they are also implicated in the development of ischaemic damage. While mitochondria do provide some mechanisms that protect against ischaemic damage (such as an endogenous inhibitor of the F1Fo-ATPase and antioxidant enzymes), they also possess a range of elements that exacerbate it, including ROS (reactive oxygen species) generators, the mitochondrial permeability transition pore, and their ability to release apoptotic factors. This review considers the process of ischaemic damage from a mitochondrial viewpoint. It considers ischaemic changes in the inner membrane complexes I-V, and how this might affect formation of ROS and high-energy phosphate production/degradation. We discuss the contribution of various mitochondrial cation channels to ionic imbalances which seem to be a major cause of reperfusion injury. The different roles of the H+, Ca2+ and the various K+ channel transporters are considered, particularly the K+(ATP) (ATP-dependent K+) channels. A possible role for the mitochondrial permeability transition pore in ischaemic damage is assessed. Finally, we summarize the metabolic and pharmacological interventions that have been used to alleviate the effects of ischaemic injury, highlighting the value of these or related interventions in possible therapeutics.
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Affiliation(s)
- Giancarlo Solaini
- *Scuola Superiore di Studi Universitari e di Perfezionamento S. Anna, Classe Accademica di Scienze Sperimentali, Piazza dei Martiri della Libertà 33, 56127 Pisa, Italy
| | - David A. Harris
- †Department of Biochemistry, University of Oxford, South Parks Rd., Oxford OX1 3QU, U.K
- To whom correspondence should be addressed (email )
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37
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Goldstein BJ, Mahadev K, Kalyankar M, Wu X. Redox paradox: insulin action is facilitated by insulin-stimulated reactive oxygen species with multiple potential signaling targets. Diabetes 2005; 54:311-21. [PMID: 15677487 PMCID: PMC1464057 DOI: 10.2337/diabetes.54.2.311] [Citation(s) in RCA: 265] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Propelled by the identification of a small family of NADPH oxidase (Nox) enzyme homologs that produce superoxide in response to cellular stimulation with various growth factors, renewed interest has been generated in characterizing the signaling effects of reactive oxygen species (ROS) in relation to insulin action. Two key observations made >30 years ago-that oxidants can facilitate or mimic insulin action and that H(2)O(2) is generated in response to insulin stimulation of its target cells-have led to the hypothesis that ROS may serve as second messengers in the insulin action cascade. Specific molecular targets of insulin-induced ROS include enzymes whose signaling activity is modified via oxidative biochemical reactions, leading to enhanced insulin signal transduction. These positive responses to cellular ROS may seem "paradoxical" because chronic exposure to relatively high levels of ROS have also been associated with functional beta-cell impairment and the chronic complications of diabetes. The best-characterized molecular targets of ROS are the protein-tyrosine phosphatases (PTPs) because these important signaling enzymes require a reduced form of a critical cysteine residue for catalytic activity. PTPs normally serve as negative regulators of insulin action via the dephosphorylation of the insulin receptor and its tyrosine-phosphorylated cellular substrates. However, ROS can rapidly oxidize the catalytic cysteine of target PTPs, effectively blocking their enzyme activity and reversing their inhibitory effect on insulin signaling. Among the cloned Nox homologs, we have recently provided evidence that Nox4 may mediate the insulin-stimulated generation of cellular ROS and is coupled to insulin action via the oxidative inhibition of PTP1B, a PTP known to be a major regulator of the insulin signaling cascade. Further characterization of the molecular components of this novel signaling cascade, including the mechanism of ROS generated by insulin and the identification of various oxidation-sensitive signaling targets in insulin-sensitive cells, may provide a novel means of facilitating insulin action in states of insulin resistance.
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Affiliation(s)
- Barry J Goldstein
- Dorrance Hamilton Research Laboratories, Division of Endocrinology, Diabetes and Metabolic Diseases, Department of Medicine, Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA 19107, USA.
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38
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Jiang XS, Dai J, Sheng QH, Zhang L, Xia QC, Wu JR, Zeng R. A comparative proteomic strategy for subcellular proteome research: ICAT approach coupled with bioinformatics prediction to ascertain rat liver mitochondrial proteins and indication of mitochondrial localization for catalase. Mol Cell Proteomics 2004; 4:12-34. [PMID: 15507458 DOI: 10.1074/mcp.m400079-mcp200] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Subcellular proteomics, as an important step to functional proteomics, has been a focus in proteomic research. However, the co-purification of "contaminating" proteins has been the major problem in all the subcellular proteomic research including all kinds of mitochondrial proteome research. It is often difficult to conclude whether these "contaminants" represent true endogenous partners or artificial associations induced by cell disruption or incomplete purification. To solve such a problem, we applied a high-throughput comparative proteome experimental strategy, ICAT approach performed with two-dimensional LC-MS/MS analysis, coupled with combinational usage of different bioinformatics tools, to study the proteome of rat liver mitochondria prepared with traditional centrifugation (CM) or further purified with a Nycodenz gradient (PM). A total of 169 proteins were identified and quantified convincingly in the ICAT analysis, in which 90 proteins have an ICAT ratio of PM:CM>1.0, while another 79 proteins have an ICAT ratio of PM:CM<1.0. Almost all the proteins annotated as mitochondrial according to Swiss-Prot annotation, bioinformatics prediction, and literature reports have a ratio of PM:CM>1.0, while proteins annotated as extracellular or secreted, cytoplasmic, endoplasmic reticulum, ribosomal, and so on have a ratio of PM:CM<1.0. Catalase and AP endonuclease 1, which have been known as peroxisomal and nuclear, respectively, have shown a ratio of PM:CM>1.0, confirming the reports about their mitochondrial location. Moreover, the 125 proteins with subcellular location annotation have been used as a testing dataset to evaluate the efficiency for ascertaining mitochondrial proteins by ICAT analysis and the bioinformatics tools such as PSORT, TargetP, SubLoc, MitoProt, and Predotar. The results indicated that ICAT analysis coupled with combinational usage of different bioinformatics tools could effectively ascertain mitochondrial proteins and distinguish contaminant proteins and even multilocation proteins. Using such a strategy, many novel proteins, known proteins without subcellular location annotation, and even known proteins that have been annotated as other locations have been strongly indicated for their mitochondrial location.
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Affiliation(s)
- Xiao-Sheng Jiang
- Research Centre for Proteome Analysis, Key Lab of Proteomics, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
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39
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Abstract
Oxidative stress results from a cell or tissue failing to detoxify the free radicals that are produced during metabolic activity. Diabetes is characterized by chronic hyperglycemia that produces dysregulation of cellular metabolism. This review explores the concept that diabetes overloads glucose metabolic pathways, resulting in excess free radical production and oxidative stress. Evidence is presented to support the idea that both chronic and acute hyperglycemia cause oxidative stress in the peripheral nervous system that can promote the development of diabetic neuropathy. Proteins that are damaged by oxidative stress have decreased biological activity leading to loss of energy metabolism, cell signaling, transport, and, ultimately, to cell death. Examination of the data from animal and cell culture models of diabetes, as well as clinical trials of antioxidants, strongly implicates hyperglycemia-induced oxidative stress in diabetic neuropathy. We conclude that striving for superior antioxidative therapies remains essential for the prevention of neuropathy in diabetic patients.
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Affiliation(s)
- Andrea M Vincent
- Department of Neurology, University of Michigan, Room 4414, Kresge III, 200 Zina Pitcher Place, Ann Arbor 48109, USA.
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40
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Li H, Singh AK, McIntyre LM, Sherman LA. Differential gene expression in response to hydrogen peroxide and the putative PerR regulon of Synechocystis sp. strain PCC 6803. J Bacteriol 2004; 186:3331-45. [PMID: 15150218 PMCID: PMC415769 DOI: 10.1128/jb.186.11.3331-3345.2004] [Citation(s) in RCA: 163] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We utilized a full genome cDNA microarray to identify the genes that comprise the peroxide stimulon in the cyanobacterium Synechocystis sp. strain PCC 6803. We determined that a gene (slr1738) encoding a protein similar to PerR in Bacillus subtilis was induced by peroxide. We constructed a PerR knockout strain and used it to help identify components of the PerR regulon, and we found that the regulatory properties were consistent with the hypothesis that PerR functions as a repressor. This effort was guided by finding putative PerR boxes in positions upstream of specific genes and by careful statistical analysis. PerR and sll1621 (ahpC), which codes for a peroxiredoxin, share a divergent promoter that is regulated by PerR. We found that isiA, encoding a Chl protein that is induced under low-iron conditions, was strongly induced by a short-term peroxide stress. Other genes that were strongly induced by peroxide included sigD, sigB, and genes encoding peroxiredoxins and Dsb-like proteins that have not been studied yet in this strain. A gene (slr1894) that encoded a protein similar to MrgA in B. subtilis was upregulated by peroxide, and a strain containing an mrgA knockout mutation was highly sensitive to peroxide. A number of genes were downregulated, including key genes in the chlorophyll biosynthesis pathway and numerous regulatory genes, including those encoding histidine kinases. We used PerR mutants and a thioredoxin mutant (TrxA1) to study differential expression in response to peroxide and determined that neither PerR nor TrxA1 is essential for the peroxide protective response.
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Affiliation(s)
- Hong Li
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA
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41
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dos Santos Soares AM, de Souza TF, de Souza Domingues SJ, Jacinto T, Tavares Machado OL. Methyl jasmonate promotes the transient reduction of the levels of 2-Cys peroxiredoxin in Ricinus communis plants. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2004; 42:543-7. [PMID: 15246068 DOI: 10.1016/j.plaphy.2004.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Accepted: 05/06/2004] [Indexed: 05/24/2023]
Abstract
Jasmonates are signaling molecules that play a key role in the regulation of metabolic processes, reproduction and defense against insects and pathogens. This study investigated the effects of methyl jasmonate on the protein pattern of Ricinus communis plants and the activity of guaiacol peroxidase, an antioxidant enzyme. Methyl jasmonate treatment caused a transient reduction in guaiacol peroxidase activity. A similar response was observed for the levels of 2-Cys peroxiredoxin protein. Moreover, the levels of the small and large chains of Rubisco were also reduced. The transient reduction of the levels and activity of antioxidant enzymes could account for the increase in the levels of H2O2, an important signaling molecule in plant defense.
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Affiliation(s)
- Alexandra Martins dos Santos Soares
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense (LQFPP/CBB/UENF), Av. Alberto Lamego, 2000, Horto, Campos dos Goytacazes CEP 28013-602, Brazil
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42
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Jones AME, Thomas V, Truman B, Lilley K, Mansfield J, Grant M. Specific changes in the Arabidopsis proteome in response to bacterial challenge: differentiating basal and R-gene mediated resistance. PHYTOCHEMISTRY 2004; 65:1805-16. [PMID: 15276439 DOI: 10.1016/j.phytochem.2004.04.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Revised: 03/30/2004] [Indexed: 05/20/2023]
Abstract
Alterations in the proteome of Arabidopsis thaliana leaves during early responses to challenge by Pseudomonas syringae pv. tomato DC3000 (DC3000) were analysed using two-dimensional (2D) gel electrophoresis. Protein changes characteristic of the establishment of basal resistance and R-gene mediated resistance were examined by comparing responses to DC3000, a hrp mutant and DC3000 expressing avrRpm1 respectively. The abundance of selected transcripts was also analysed in GeneChip experiments. Here we present data from the soluble fraction of leaf protein, highlighting changes in two antioxidant enzyme groups; the glutathione S-transferases (GSTs F2, F6, F7 and F8) and peroxiredoxins (PrxA, B and IIE). Members of both enzyme groups showed signs of specific post-translational modifications, represented by multiple spots on gels. We suggest that oxidation of specific residues is responsible for some of the spot shifts. All forms of the GST proteins identified here increased following inoculation with bacteria. GSTF8 showed particularly dynamic responses to pathogen challenge, the corresponding transcript was significantly up-regulated by 2 h after inoculation, and the protein showed post-translational modifications specific to an incompatible interaction. Differential changes were observed with the peroxiredoxin proteins; PrxIIE and to a lesser extent PrxB, no change was observed with PrxA, but a truncated form PrxA-L was greatly reduced in abundance following bacterial challenges. Our data suggest that bacterial challenge generally induces Prxs and the antioxidants GSTs, however individual members of these families may be specifically modified dependent upon the virulence of the DC3000 strain and outcome of the interaction. Finally, proteomic and transcriptomic data derived from the same inoculation system are compared and the advantages offered by 2D gel analysis discussed in light of our results.
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Affiliation(s)
- Alexandra M E Jones
- Department of Agricultural Science, Imperial College London, Wye Campus, High Street, Wye TN25 5AH, UK.
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43
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Jang HH, Lee KO, Chi YH, Jung BG, Park SK, Park JH, Lee JR, Lee SS, Moon JC, Yun JW, Choi YO, Kim WY, Kang JS, Cheong GW, Yun DJ, Rhee SG, Cho MJ, Lee SY. Two Enzymes in One. Cell 2004; 117:625-35. [PMID: 15163410 DOI: 10.1016/j.cell.2004.05.002] [Citation(s) in RCA: 589] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2003] [Revised: 03/31/2004] [Accepted: 04/06/2004] [Indexed: 11/30/2022]
Abstract
Although a great deal is known biochemically about peroxiredoxins (Prxs), little is known about their real physiological function. We show here that two cytosolic yeast Prxs, cPrxI and II, which display diversity in structure and apparent molecular weights (MW), can act alternatively as peroxidases and molecular chaperones. The peroxidase function predominates in the lower MW forms, whereas the chaperone function predominates in the higher MW complexes. Oxidative stress and heat shock exposure of yeasts causes the protein structures of cPrxI and II to shift from low MW species to high MW complexes. This triggers a peroxidase-to-chaperone functional switch. These in vivo changes are primarily guided by the active peroxidase site residue, Cys(47), which serves as an efficient "H(2)O(2)-sensor" in the cells. The chaperone function of these proteins enhances yeast resistance to heat shock.
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Affiliation(s)
- Ho Hee Jang
- Division of Applied Life Sciences, Gyeonsang National University, Chinju, 660-701, South Korea
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44
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Becker K, Tilley L, Vennerstrom JL, Roberts D, Rogerson S, Ginsburg H. Oxidative stress in malaria parasite-infected erythrocytes: host–parasite interactions. Int J Parasitol 2004; 34:163-89. [PMID: 15037104 DOI: 10.1016/j.ijpara.2003.09.011] [Citation(s) in RCA: 420] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2003] [Revised: 09/18/2003] [Accepted: 09/18/2003] [Indexed: 01/09/2023]
Abstract
Experimenta naturae, like the glucose-6-phosphate dehydrogenase deficiency, indicate that malaria parasites are highly susceptible to alterations in the redox equilibrium. This offers a great potential for the development of urgently required novel chemotherapeutic strategies. However, the relationship between the redox status of malarial parasites and that of their host is complex. In this review article we summarise the presently available knowledge on sources and detoxification pathways of reactive oxygen species in malaria parasite-infected red cells, on clinical aspects of redox metabolism and redox-related mechanisms of drug action as well as future prospects for drug development. As delineated below, alterations in redox status contribute to disease manifestation including sequestration, cerebral pathology, anaemia, respiratory distress, and placental malaria. Studying haemoglobinopathies, like thalassemias and sickle cell disease, and other red cell defects that provide protection against malaria allows insights into this fine balance of redox interactions. The host immune response to malaria involves phagocytosis as well as the production of nitric oxide and oxygen radicals that form part of the host defence system and also contribute to the pathology of the disease. Haemoglobin degradation by the malarial parasite produces the redox active by-products, free haem and H(2)O(2), conferring oxidative insult on the host cell. However, the parasite also supplies antioxidant moieties to the host and possesses an efficient enzymatic antioxidant defence system including glutathione- and thioredoxin-dependent proteins. Mechanistic and structural work on these enzymes might provide a basis for targeting the parasite. Indeed, a number of currently used drugs, especially the endoperoxide antimalarials, appear to act by increasing oxidant stress, and novel drugs such as peroxidic compounds and anthroquinones are being developed.
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Affiliation(s)
- Katja Becker
- Interdisciplinary Research Center, Heinrich-Buff-Ring 26-32, Justus-Liebig University, D-35392 Giessen, Germany.
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45
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Goulding CW, Apostol MI, Gleiter S, Parseghian A, Bardwell J, Gennaro M, Eisenberg D. Gram-positive DsbE proteins function differently from Gram-negative DsbE homologs. A structure to function analysis of DsbE from Mycobacterium tuberculosis. J Biol Chem 2003; 279:3516-24. [PMID: 14597624 DOI: 10.1074/jbc.m311833200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Mycobacterium tuberculosis, a Gram-positive bacterium, encodes a secreted Dsb-like protein annotated as Mtb DsbE (Rv2878c, also known as MPT53). Because Dsb proteins in Escherichia coli and other bacteria seem to catalyze proper folding during protein secretion and because folding of secreted proteins is thought to be coupled to disulfide oxidoreduction, the function of Mtb DsbE may be to ensure that secreted proteins are in their correctly folded states. We have determined the crystal structure of Mtb DsbE to 1.1 A resolution, which reveals a thioredoxin-like domain with a typical CXXC active site. These cysteines are in their reduced state. Biochemical characterization of Mtb DsbE reveals that this disulfide oxidoreductase is an oxidant, unlike Gram-negative bacteria DsbE proteins, which have been shown to be weak reductants. In addition, the pK(a) value of the active site, solvent-exposed cysteine is approximately 2 pH units lower than that of Gram-negative DsbE homologs. Finally, the reduced form of Mtb DsbE is more stable than the oxidized form, and Mtb DsbE is able to oxidatively fold hirudin. Structural and biochemical analysis implies that Mtb DsbE functions differently from Gram-negative DsbE homologs, and we discuss its possible functional role in the bacterium.
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MESH Headings
- Amino Acid Sequence
- Antigens, Bacterial/chemistry
- Antigens, Bacterial/physiology
- Bacterial Proteins/chemistry
- Bacterial Proteins/physiology
- Binding Sites
- Catalysis
- Crystallography, X-Ray
- Cysteine/chemistry
- Cytoplasm/metabolism
- Databases, Genetic
- Dimerization
- Disulfides/chemistry
- Dose-Response Relationship, Drug
- Escherichia coli/metabolism
- Gram-Negative Bacteria/metabolism
- Gram-Positive Bacteria/metabolism
- Hirudins/chemistry
- Hydrogen-Ion Concentration
- Kinetics
- Models, Biological
- Models, Molecular
- Molecular Sequence Data
- Mycobacterium tuberculosis/metabolism
- Oxidation-Reduction
- Oxidoreductases/chemistry
- Oxygen/metabolism
- Plasmids/metabolism
- Protein Conformation
- Protein Folding
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Sequence Homology, Amino Acid
- Structure-Activity Relationship
- Sulfhydryl Compounds
- Thermodynamics
- X-Ray Diffraction
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Affiliation(s)
- Celia W Goulding
- Howard Hughes Medical Institute and UCLA-Department of Energy Institute of Genomics and Proteomics, Los Angeles, California 90095-1570
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46
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Bréhélin C, Meyer EH, de Souris JP, Bonnard G, Meyer Y. Resemblance and dissemblance of Arabidopsis type II peroxiredoxins: similar sequences for divergent gene expression, protein localization, and activity. PLANT PHYSIOLOGY 2003; 132:2045-57. [PMID: 12913160 PMCID: PMC181289 DOI: 10.1104/pp.103.022533] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2003] [Revised: 03/14/2003] [Accepted: 04/28/2003] [Indexed: 05/18/2023]
Abstract
The Arabidopsis type II peroxiredoxin (PRXII) family is composed of six different genes, five of which are expressed. On the basis of the nucleotide and protein sequences, we were able to define three subgroups among the PRXII family. The first subgroup is composed of AtPRXII-B, -C, and -D, which are highly similar and localized in the cytosol. AtPRXII-B is ubiquitously expressed. More striking is the specific expression of AtPRXII-C and AtPRXII-D localized in pollen. The second subgroup comprises the mitochondrial AtPRXII-F, the corresponding gene of which is expressed constitutively. We show that AtPRXII-E, belonging to the last subgroup, is expressed mostly in reproductive tissues and that its product is addressed to the plastid. By in vitro enzymatic experiments, we demonstrate that glutaredoxin is the electron donor of recombinant AtPRXII-B for peroxidase reaction, but the donors of AtPRXII-E and AtPRXII-F have still to be identified.
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Affiliation(s)
- Claire Bréhélin
- Laboratoire Génome et Développement des Plantes, Université de Perpignan, Unité Mixte de Recherche Centre National de la Recherche Scientifique 5096, 52 avenue de Villeneuve, 66860 Perpignan, France
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Jeon SJ, Ishikawa K. Characterization of novel hexadecameric thioredoxin peroxidase from Aeropyrum pernix K1. J Biol Chem 2003; 278:24174-80. [PMID: 12707274 DOI: 10.1074/jbc.m300618200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A gene (APE2278) encoding the peroxiredoxin (Prx) homologous protein of yeast and human was identified in the genome data base of the aerobic hyperthermophilic archaeon Aeropyrum pernix. We cloned the gene and produced the encoded protein in Escherichia coli cells. The isolated recombinant protein showed peroxidase activity in vitro and used the thioredoxin system of A. pernix as an electron donor. These results indicate that the recombinant protein is in fact thioredoxin peroxidase (ApTPx) of A. pernix. Immunoblot analysis revealed that the expression of ApTPx was induced as a cellular adaptation in response to the addition of exogenous H2O2 and may exert an antioxidant activity in vivo. An analysis of the ApTPx oligomers by high pressure liquid chromatography and electron microscopic studies showed that ApTPx exhibited the hexadecameric protein forming 2-fold toroid-shaped structure with outer and inner diameters of 14 and 6 nm, respectively. These results indicated that ApTPx is a novel hexadecameric protein composed of two identical octamers. Although oligomerization of individual subunits does not take place through an intersubunit-disulfide linkage involving Cys50 and Cys213, Cys50 is essential for the formation of the hexadecamer. Mutagenesis studies suggest that the sulfhydryl group of Cys50 is the site of oxidation by peroxide and that oxidized Cys50 reacts with the sulfhydryl group of Cys213 of another subunit to form an intermolecular disulfide bond. The resulting disulfide can then be reduced by thioredoxin. In support of this hypothesis, ApTPx mutants lacking either Cys50 or Cys213 showed no TPx activity, whereas the mutant lacking Cys207 had a TPx activity. This is the first report on the biochemical and structural features of a novel hexadecameric thioredoxin peroxidase from the archaea.
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Affiliation(s)
- Sung-Jong Jeon
- National Institute of Advanced Industrial Science and Technology (AIST Kansai), Ikeda, Osaka 563-8577, Japan
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Becker K, Rahlfs S, Nickel C, Schirmer RH. Glutathione--functions and metabolism in the malarial parasite Plasmodium falciparum. Biol Chem 2003; 384:551-66. [PMID: 12751785 DOI: 10.1515/bc.2003.063] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
When present as a trophozoite in human erythrocytes, the malarial parasite Plasmodium falciparum exhibits an intense glutathione metabolism. Glutathione plays a role not only in antioxidative defense and in maintaining the reducing environment of the cytosol. Many of the known glutathione-dependent processes are directly related to the specific lifestyle of the parasite. Reduced glutathione (GSH) supports rapid cell growth by providing electrons for deoxyribonucleotide synthesis and it takes part in detoxifying heme, a product of hemoglobin digestion. Free radicals generated in the parasite can be scavenged in reaction sequences involving the thiyl radical GS* as well as the thiolate GS-. As a substrate of glutathione S-transferase, glutathione is conjugated to non-degradable compounds including antimalarial drugs. Furthermore, it is the coenzyme of the glyoxalase system which detoxifies methylglyoxal, a byproduct of the intense glycolysis taking place in the trophozoite. Proteins involved in GSH-dependent processes include glutathione reductase, glutaredoxins, glyoxalase I and II, glutathione S-transferases, and thioredoxins. These proteins, as well as the ATP-dependent enzymes of glutathione synthesis, are studied as factors in the pathophysiology of malaria but also as potential drug targets. Methylene blue, an inhibitor of the structurally known P. falciparum glutathione reductase, appears to be a promising antimalarial medication when given in combination with chloroquine.
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Affiliation(s)
- Katja Becker
- Interdisciplinary Research Center, Justus-Liebig-University, D-35392 Giessen, Germany
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Nunn CM, Djordjevic S, Hillas PJ, Nishida CR, Ortiz de Montellano PR. The crystal structure of Mycobacterium tuberculosis alkylhydroperoxidase AhpD, a potential target for antitubercular drug design. J Biol Chem 2002; 277:20033-40. [PMID: 11914371 DOI: 10.1074/jbc.m200864200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The resistance of Mycobacterium tuberculosis to isoniazid is commonly linked to inactivation of a catalase-peroxidase, KatG, that converts isoniazid to its biologically active form. Loss of KatG is associated with elevated expression of the alkylhydroperoxidases AhpC and AhpD. AhpD has no sequence identity with AhpC or other proteins but has alkylhydroperoxidase activity and possibly additional physiological activities. The alkylhydroperoxidase activity, in the absence of KatG, provides an important antioxidant defense. We have determined the M. tuberculosis AhpD structure to a resolution of 1.9 A. The protein is a trimer in a symmetrical cloverleaf arrangement. Each subunit exhibits a new all-helical protein fold in which the two catalytic sulfhydryl groups, Cys-130 and Cys-133, are located near a central cavity in the trimer. The structure supports a mechanism for the alkylhydroperoxidase activity in which Cys-133 is deprotonated by a distant glutamic acid via the relay action of His-137 and a water molecule. The cysteine then reacts with the peroxide to give a sulfenic acid that subsequently forms a disulfide bond with Cys-130. The crystal structure of AhpD identifies a new protein fold relevant to members of this protein family in other organisms. The structural details constitute a potential platform for the design of inhibitors of potential utility as antitubercular agents and suggest that AhpD may have disulfide exchange properties of importance in other areas of M. tuberculosis biology.
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Affiliation(s)
- Christine M Nunn
- Department of Biochemistry and Molecular Biology, University College, Gower Street, London WC1E 6BT, United Kingdom
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Abstract
The ingredients of oxidative stress include a variety of reactive species such as reactive oxygen and reactive nitrogen species (ROS, RNS). While sulfur is usually considered as part of cellular antioxidant systems there is mounting evidence that reactive sulfur species (RSS) with stressor properties similar to the ones found in ROS are formed under conditions of oxidative stress. Thiols as well as disulfides are easily oxidised to sulfur species with sulfur in higher oxidation states. Such agents include thiyl radicals, disulfides, sulfenic acids and disulfide-S-oxides. They rapidly oxidise and subsequently inhibit thiol-proteins and enzymes and can be considered as a separate class of oxidative stressors providing new antioxidant drug targets.
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