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Morrin ST, Buck RH, Farrow M, Hickey RM. Milk-derived anti-infectives and their potential to combat bacterial and viral infection. J Funct Foods 2021. [DOI: 10.1016/j.jff.2021.104442] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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2
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Al-Shehri SS. Reactive oxygen and nitrogen species and innate immune response. Biochimie 2020; 181:52-64. [PMID: 33278558 DOI: 10.1016/j.biochi.2020.11.022] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 11/21/2020] [Accepted: 11/30/2020] [Indexed: 12/30/2022]
Abstract
The innate immune system is the first line of defense against pathogens and is characterized by its fast but nonspecific response. One important mechanism of this system is the production of the biocidal reactive oxygen and nitrogen species, which are widely distributed within biological systems, including phagocytes and secretions. Reactive oxygen and nitrogen species are short-lived intermediates that are biochemically synthesized by various enzymatic reactions in aerobic organisms and are regulated by antioxidants. The physiological levels of reactive species play important roles in cellular signaling and proliferation. However, higher concentrations and prolonged exposure can fight infections by damaging important microbial biomolecules. One feature of the reactive species generation system is the interaction between its components to produce more biocidal agents. For example, the phagocytic NADPH oxidase complex generates superoxide, which functions as a precursor for antimicrobial hydrogen peroxide synthesis. Peroxide is then used by myeloperoxidase in the same cells to generate hypochlorous acid, a highly microbicidal agent. Studies on animal models and microorganisms have shown that deficiency of these antimicrobial agents is associated with severe recurrent infections and immunocompromised diseases, such as chronic granulomatous disease. There is accumulating evidence that reactive species have important positive aspects on human health and immunity; however, some important promising features of this system remain obscure.
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Affiliation(s)
- Saad S Al-Shehri
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, P. O. Box 11099, Taif, 21944, Saudi Arabia.
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3
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Zhao G, Wang YF, Chen J, Yao Y. Predominant Mycotoxins, Pathogenesis, Control Measures, and Detection Methods in Fermented Pastes. Toxins (Basel) 2020; 12:E78. [PMID: 31979410 PMCID: PMC7076863 DOI: 10.3390/toxins12020078] [Citation(s) in RCA: 4] [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: 01/02/2020] [Revised: 01/12/2020] [Accepted: 01/21/2020] [Indexed: 12/19/2022] Open
Abstract
Fermented pastes are some of the most popular traditional products in China. Many studies reported a strong possibility that fermented pastes promote exposure to mycotoxins, including aflatoxins, ochratoxins, and cereulide, which were proven to be carcinogenic and neurotoxic to humans. The primary mechanism of pathogenicity is by inhibiting protein synthesis and inducing oxidative stress using cytochrome P450 (CYP) enzymes. The level of mycotoxin production is dependent on the pre-harvest or post-harvest stage. It is possible to implement methods to control mycotoxins by using appropriate antagonistic microorganisms, such as Aspergillus niger, Lactobacillus plantarum, and Saccharomyces cerevisiae isolated from ordinary foods. Also, drying products as soon as possible to avoid condensation or moisture absorption in order to reduce the water activity to lower than 0.82 during storage is also effective. Furthermore, organic acid treatment during the soaking process reduces toxins by more than 90%. Some novel detection technologies based on magnetic adsorption, aptamer probes, and molecular-based methods were applied to rapidly and accurately detect mycotoxins in fermented pastes.
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Affiliation(s)
- Guozhong Zhao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Science and Engineering, Tianjin University of Science & Technology, 300457 Tianjin, China; (G.Z.); (Y.-F.W.)
| | - Yi-Fei Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Science and Engineering, Tianjin University of Science & Technology, 300457 Tianjin, China; (G.Z.); (Y.-F.W.)
| | - Junling Chen
- College of Food and Bioengineering, Henan University of Science and Technology, 471023 Luoyang, China;
| | - Yunping Yao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Science and Engineering, Tianjin University of Science & Technology, 300457 Tianjin, China; (G.Z.); (Y.-F.W.)
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4
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Nakano M, Suzuki M, Wakabayashi H, Hayama K, Yamauchi K, Abe F, Abe S. Synergistic anti-candida activities of lactoferrin and the lactoperoxidase system. Drug Discov Ther 2019; 13:28-33. [PMID: 30880319 DOI: 10.5582/ddt.2019.01010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Candida albicans is a commensal fungus in human mucosal surfaces, including the oral cavity. Lactoferrin (LF) and the lactoperoxidase (LPO) system, which are host protection components in exocrine secretions, each exhibit weak anti-candida activity. We herein examined the effects of the combination of LF and the LPO system on C. albicans. Morphological observations indicated that the combination of LF and the LPO system reduced the mycelial volume of C. albicans and changed the size and shape of cells more than each agent alone. The combination of LF and the LPO system also exerted strong inhibitory effects on the cellular metabolic activity and adhesive hyphal form of C. albicans. A checkerboard analysis revealed that the anti-candida activity of LF and the LPO system was synergistic. These results suggest that the combination of LF and the LPO system is useful for preventing candidiasis.
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Affiliation(s)
- Manabu Nakano
- Food Ingredients & Technology Institute, R&D Division, Morinaga Milk Industry Co., Ltd
| | | | - Hiroyuki Wakabayashi
- Food Ingredients & Technology Institute, R&D Division, Morinaga Milk Industry Co., Ltd
| | | | - Koji Yamauchi
- Food Ingredients & Technology Institute, R&D Division, Morinaga Milk Industry Co., Ltd
| | - Fumiaki Abe
- Food Ingredients & Technology Institute, R&D Division, Morinaga Milk Industry Co., Ltd
| | - Shigeru Abe
- Teikyo University Institute of Medical Mycology
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5
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The science of licking your wounds: Function of oxidants in the innate immune system. Biochem Pharmacol 2019; 163:451-457. [DOI: 10.1016/j.bcp.2019.03.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 03/08/2019] [Indexed: 02/07/2023]
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6
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Magacz M, Kędziora K, Sapa J, Krzyściak W. The Significance of Lactoperoxidase System in Oral Health: Application and Efficacy in Oral Hygiene Products. Int J Mol Sci 2019; 20:ijms20061443. [PMID: 30901933 PMCID: PMC6472183 DOI: 10.3390/ijms20061443] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 03/13/2019] [Accepted: 03/18/2019] [Indexed: 12/13/2022] Open
Abstract
Lactoperoxidase (LPO) present in saliva are an important element of the nonspecific immune response involved in maintaining oral health. The main role of this enzyme is to oxidize salivary thiocyanate ions (SCN-) in the presence of hydrogen peroxide (H₂O₂) to products that exhibit antimicrobial activity. LPO derived from bovine milk has found an application in food, cosmetics, and medical industries due to its structural and functional similarity to the human enzyme. Oral hygiene products enriched with the LPO system constitute an alternative to the classic fluoride caries prophylaxis. This review describes the physiological role of human salivary lactoperoxidase and compares the results of clinical trials and in vitro studies of LPO alone and complex dentifrices enriched with bovine LPO. The role of reactivators and inhibitors of LPO is discussed together with the possibility of using nanoparticles to increase the stabilization and activity of this enzyme.
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Affiliation(s)
- Marcin Magacz
- Department of Medical Diagnostics, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland.
| | - Karolina Kędziora
- Department of Medical Diagnostics, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland.
| | - Jacek Sapa
- Department of Pharmacodynamics, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland.
| | - Wirginia Krzyściak
- Department of Medical Diagnostics, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland.
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7
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Effect of the Nature and Relative Concentration of Substrate, Water Mineralization, and Storage Temperature on the Oxidants Produced by Lactoperoxidase and on Their Antifungal Activity against Penicillium expansum and Botrytis cinerea. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9010197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Lactoperoxidase is an enzyme that generates oxidants with antimicrobial activity in presence of a (pseudo)halogen and hydrogen peroxide, but various factors can drastically reduce the antimicrobial activity of the lactoperoxidase system. Spectroscopic, ionic chromatography, and 13C-NMR methods showed that the oxidants generated by lactoperoxidase are OSCN− in the presence of SCN− and I2 in the presence of I−. Neither of them, however, inhibited Penicillium expansum, one of the causal agents of fruit mold. When a mixture of SCN− and I− was used, no OSCN−, OCN−, I2, or interhalogen I2SCN− was produced. However, its long-term stability, NH2-oxidizing capacity, and antifungal activity against P. expansum argue in favor of an I−-derived oxidant. Strongly mineralized water optimized enzyme-catalyzed reactions with higher oxidant production. Storage at 4 °C resulted in long-term stability and extended antifungal activity against P. expansum. The relative iodide/thiocyanate concentrations turned out to be important, as better in vitro inhibition of Botrytis cinerea, the causal agent of apples’s grey mold, was obtained with a high KI + KSCN concentration, a KI/KSCN ratio of 4.5, and a (KI + KSCN)/H2O2 ratio of 1. The nature of the substrates, their relative concentrations, the medium, and the storage temperature modifed the antifungal activity of lactoperoxidase.
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8
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Antimicrobial actions of dual oxidases and lactoperoxidase. J Microbiol 2018; 56:373-386. [PMID: 29858825 DOI: 10.1007/s12275-018-7545-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/16/2018] [Accepted: 02/19/2018] [Indexed: 12/11/2022]
Abstract
The NOX/DUOX family of NADPH oxidases are transmembrane proteins generating reactive oxygen species as their primary enzymatic products. NADPH oxidase (NOX) 1-5 and Dual oxidase (DUOX) 1 and 2 are members of this family. These enzymes have several biological functions including immune defense, hormone biosynthesis, fertilization, cell proliferation and differentiation, extracellular matrix formation and vascular regulation. They are found in a variety of tissues such as the airways, salivary glands, colon, thyroid gland and lymphoid organs. The discovery of NADPH oxidases has drastically transformed our view of the biology of reactive oxygen species and oxidative stress. Roles of several isoforms including DUOX1 and DUOX2 in host innate immune defense have been implicated and are still being uncovered. DUOX enzymes highly expressed in the respiratory and salivary gland epithelium have been proposed as the major sources of hydrogen peroxide supporting mucosal oxidative antimicrobial defenses. In this review, we shortly present data on DUOX discovery, structure and function, and provide a detailed, up-to-date summary of discoveries regarding antibacterial, antiviral, antifungal, and antiparasitic functions of DUOX enzymes. We also present all the literature describing the immune functions of lactoperoxidase, an enzyme working in partnership with DUOX to produce antimicrobial substances.
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9
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Willemin ME, Lumen A. Thiocyanate: a review and evaluation of the kinetics and the modes of action for thyroid hormone perturbations. Crit Rev Toxicol 2017. [DOI: 10.1080/10408444.2017.1281590] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Marie-Emilie Willemin
- Division of Biochemical Toxicology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR, USA
| | - Annie Lumen
- Division of Biochemical Toxicology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR, USA
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10
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Nakano M, Shin K, Wakabayashi H, Yamauchi K, Abe F, Hironaka S. Inactivating effects of the lactoperoxidase system on bacterial lyases involved in oral malodour production. J Med Microbiol 2015; 64:1244-1252. [PMID: 26242770 DOI: 10.1099/jmm.0.000150] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The main components of oral malodour have been identified as volatile sulfur compounds (VSCs), including hydrogen sulfide (H(2)S) and methyl mercaptan (CH(3)SH). The lactoperoxidase (LPO) system (consisting of LPO, glucose oxidase, glucose and thiocyanate) was previously shown to exhibit antimicrobial activities against some oral bacteria in vitro and suppressive effects on VSCs in mouth air in a clinical trial. Here, we examined the in vitro effects of the LPO system on the activities of the bacterial lyases involved in the production of VSCs by oral anaerobes. The exposure of crude bacterial extracts of Fusobacterium nucleatum and Porphyromonas gingivalis or purified methionine γ-lyase to the LPO system resulted in the inactivation of their lyase activities through l-cysteine and l-methionine, which was linked to the production of H(2)S and CH(3)SH, respectively. The exposure of living F. nucleatum and P. gingivalis cells to the LPO system resulted in the suppression of cell numbers and lyase activities. The inactivation of the crude bacterial extracts of F. nucleatum and purified methionine γ-lyase by the LPO system was partly recovered by the addition of DTT. Therefore, the LPO system may inactivate bacterial lyases including methionine γ-lyase by reacting with the free cysteine residues of lyases. These results suggested that the LPO system suppresses the production of VSCs not only through its antimicrobial effects, but also by its inactivating effects on the bacterial lyases of F. nucleatum and P. gingivalis.
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Affiliation(s)
- Manabu Nakano
- Food Ingredients & Technology Institute, Morinaga Milk Industry Co., Ltd, 5-1-83 Higashihara, Zama, Kanagawa 252-8583, Japan
| | - Kouichirou Shin
- Food Ingredients & Technology Institute, Morinaga Milk Industry Co., Ltd, 5-1-83 Higashihara, Zama, Kanagawa 252-8583, Japan
| | - Hiroyuki Wakabayashi
- Food Ingredients & Technology Institute, Morinaga Milk Industry Co., Ltd, 5-1-83 Higashihara, Zama, Kanagawa 252-8583, Japan
| | - Koji Yamauchi
- Food Ingredients & Technology Institute, Morinaga Milk Industry Co., Ltd, 5-1-83 Higashihara, Zama, Kanagawa 252-8583, Japan
| | - Fumiaki Abe
- Food Ingredients & Technology Institute, Morinaga Milk Industry Co., Ltd, 5-1-83 Higashihara, Zama, Kanagawa 252-8583, Japan
| | - Shouji Hironaka
- Department of Special Needs Dentistry, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
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11
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Chandler JD, Day BJ. Biochemical mechanisms and therapeutic potential of pseudohalide thiocyanate in human health. Free Radic Res 2015; 49:695-710. [PMID: 25564094 DOI: 10.3109/10715762.2014.1003372] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Thiocyanate (SCN(-)) is a ubiquitous molecule in mammalian biology, reaching up to mM concentrations in extracellular fluids. Two- electron oxidation of SCN(-) by H2O2 produces hypothiocyanous acid (HOSCN), a potent anti-microbial species. This reaction is catalyzed by chordate peroxidases (e.g., myeloperoxidase and lactoperoxidase), occurring in human secretory mucosa, including the oral cavity, airway, and alimentary tract, and regulates resident and transient flora as part of innate immunity. Increasing SCN(-) levels limits the concentrations of a family of 2-electron oxidants (H2O2, hypohalous acids, and haloamines) in favor of HOSCN formation, altering the oxidative impact on host tissue by substitution of repairable thiol and selenol oxidations instead of biomolecule degradation. This fine-tuning of inflammatory oxidation paradoxically associates with maintained host defense and decreased host injury during infections, due in part to phylogenetic differences in the thioredoxin reductase system between mammals and their pathogens. These differences could be exploited by pharmacologic use of SCN(-). Recent preclinical studies have identified anti-microbial and anti-inflammatory effects of SCN(-) in pulmonary and cardiovascular animal models, with implications for treatment of infectious lung disease and atherogenesis. Further research is merited to expand on these findings and identify other diseases where SCN(-) may be of use. High oral bioavailability and an increased knowledge of the biochemical effects of SCN(-) on a subset of pro-inflammatory reactions suggest clinical utility.
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12
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Sharma S, Singh AK, Kaushik S, Sinha M, Singh RP, Sharma P, Sirohi H, Kaur P, Singh TP. Lactoperoxidase: structural insights into the function,ligand binding and inhibition. INTERNATIONAL JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 4:108-128. [PMID: 24049667 PMCID: PMC3776144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 08/21/2013] [Indexed: 06/02/2023]
Abstract
Lactoperoxidase (LPO) is a member of a large group of mammalian heme peroxidases that include myeloperoxidase (MPO), eosinophil peroxidase (EPO) and thyroid peroxidase (TPO). The LPO is found in exocrine secretions including milk. It is responsible for the inactivation of a wide range of micro-organisms and hence, is an important component of defense mechanism in the body. With the help of hydrogen peroxide, it catalyzes the oxidation of halides, pseudohalides and organic aromatic molecules. Historically, LPO was isolated in 1943, nearly seventy years ago but its three-dimensional crystal structure has been elucidated only recently. This review provides various details of this protein from its discovery to understanding its structure, function and applications. In order to highlight species dependent variations in the structure and function of LPO, a detailed comparison of sequence, structure and function of LPO from various species have been made. The structural basis of ligand binding and distinctions in the modes of binding of substrates and inhibitors have been analyzed extensively.
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Affiliation(s)
- Sujata Sharma
- Department of Biophysics, All India Institute of Medical Sciences New Delhi - 110029, India
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13
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Cooper RA. Inhibition of biofilms by glucose oxidase, lactoperoxidase and guaiacol: the active antibacterial component in an enzyme alginogel. Int Wound J 2013; 10:630-7. [PMID: 23672196 DOI: 10.1111/iwj.12083] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The association of biofilms with wound chronicity has prompted a search for antimicrobial interventions that are effective against biofilms. A patented preparation of glucose oxidase, lactoperoxidase and guaiacol (GLG), which is the antibacterial component of Flaminal, has been shown to inhibit a wide range of bacteria, but it has not yet been tested on biofilms. This study aims to determine the effect of GLG on biofilms of Staphylococcus aureus, methicillin-resistant S. aureus and Pseudomonas aeruginosa. Static biofilms were grown in microtitre plates and on coverslips and treated with a range of concentrations of GLG. Effects were monitored by estimating biofilm biomass by staining with crystal violet, biofilm activity by staining with either resazurin or fluorescein diacetate and biofilm viability by staining with LIVE/DEAD BacLight Bacterial Viability Kit. GLG was able to prevent the formation of biofilms at concentration ≤0.5% (w/v) and higher concentrations were required to inhibit established biofilms. GLG did not disrupt biofilm biomass. Staphylococci were more susceptible to GLG than P. aeruginosa. These in vitro findings must be verified by in vivo studies.
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Affiliation(s)
- Rose A Cooper
- Centre for Biomedical Sciences, Cardiff School of Health Sciences, Cardiff Metropolitan University, Cardiff, UK
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14
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Chandler JD, Nichols DP, Nick JA, Hondal RJ, Day BJ. Selective metabolism of hypothiocyanous acid by mammalian thioredoxin reductase promotes lung innate immunity and antioxidant defense. J Biol Chem 2013; 288:18421-8. [PMID: 23629660 DOI: 10.1074/jbc.m113.468090] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The endogenously produced oxidant hypothiocyanous acid (HOSCN) inhibits and kills pathogens but paradoxically is well tolerated by mammalian host tissue. Mammalian high molecular weight thioredoxin reductase (H-TrxR) is evolutionarily divergent from bacterial low molecular weight thioredoxin reductase (L-TrxR). Notably, mammalian H-TrxR contains a selenocysteine (Sec) and has wider substrate reactivity than L-TrxR. Recombinant rat cytosolic H-TrxR1, mouse mitochondrial H-TrxR2, and a purified mixture of both from rat selectively turned over HOSCN (kcat = 357 ± 16 min(-1); Km = 31.9 ± 10.3 μM) but were inactive against the related oxidant hypochlorous acid. Replacing Sec with Cys or deleting the final eight C-terminal peptides decreased affinity and turnover of HOSCN by H-TrxR. Similarly, glutathione reductase (an H-TrxR homologue lacking Sec) was less effective at HOSCN turnover. In contrast to H-TrxR and glutathione reductase, recombinant Escherichia coli L-TrxR was potently inhibited by HOSCN (IC50 = 2.75 μM). Similarly, human bronchial epithelial cell (16HBE) lysates metabolized HOSCN, but E. coli and Pseudomonas aeruginosa lysates had little or no activity. HOSCN selectively produced toxicity in bacteria, whereas hypochlorous acid was nonselectively toxic to both bacteria and 16HBE. Treatment with the H-TrxR inhibitor auranofin inhibited HOSCN metabolism in 16HBE lysates and significantly increased HOSCN-mediated cytotoxicity. These findings demonstrate both the metabolism of HOSCN by mammalian H-TrxR resulting in resistance to HOSCN in mammalian cells and the potent inhibition of bacterial L-TrxR resulting in cytotoxicity in bacteria. These data support a novel selective mechanism of host defense in mammals wherein HOSCN formation simultaneously inhibits pathogens while sparing host tissue.
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Affiliation(s)
- Joshua D Chandler
- Department of Pharmaceutical Sciences, University of Colorado Denver, Aurora, Colorado 80045, USA
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15
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Chandler JD, Day BJ. Thiocyanate: a potentially useful therapeutic agent with host defense and antioxidant properties. Biochem Pharmacol 2012; 84:1381-7. [PMID: 22968041 DOI: 10.1016/j.bcp.2012.07.029] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 07/26/2012] [Accepted: 07/26/2012] [Indexed: 12/15/2022]
Abstract
Thiocyanate (SCN) functions in host defense as part of the secreted lactoperoxidase (LPO) microbicidal pathway. SCN is the preferred substrate for LPO-driven catalytic reduction of hydrogen peroxide (H(2)O(2)) forming hypothiocyanous acid (HOSCN). HOSCN is selectively generated by many peroxidase enzymes that can utilize SCN including: eosinophil peroxidase (EPO), gastric peroxidase (GPO), myeloperoxidase (MPO), salivary peroxidase (SPO), and thyroid peroxidase (TPO). These enzymes generate HOSCN through a two-electron halogenation reaction. HOSCN is a potent microbicidal agent that kills or nullifies invading pathogens but is better tolerated by host tissue. Some controversy exists as to whether physiologic levels of HOSCN are non-toxic to host tissue, but the disagreement appears to be based on results of enzymatic generation (yielding moderate steady-state exposure) versus direct high level acute exposure in mammalian cell lines. This apparent duality is also true of other endogenous oxidants such as hydrogen peroxide and relates to the difference between physiologically relevant oxidant production versus supra-physiologic bolus dosing approaches. SCN has antioxidant properties that include the ability to protect cells against oxidizing agents such as hypochlorous acid (HOCl) and repair protein chloramines. SCN is an important endogenous molecule that has the potential to interact in complex and elegant ways with its host environment and foreign organisms. SCN's diverse properties as both host defense and antioxidant agent make it a potentially useful therapeutic.
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Affiliation(s)
- Joshua D Chandler
- Department of Medicine, National Jewish Health, Denver, CO 80206, United States
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16
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Nauseef WM. Nox enzymes in immune cells. Semin Immunopathol 2008; 30:195-208. [DOI: 10.1007/s00281-008-0117-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Accepted: 04/02/2008] [Indexed: 01/08/2023]
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17
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Shin K, Horigome A, Wakabayashi H, Yamauchi K, Yaeshima T, Iwatsuki K. In vitro
and
in vivo
effects of a composition containing lactoperoxidase on oral bacteria and breath odor. J Breath Res 2008; 2:017014. [DOI: 10.1088/1752-7155/2/1/017014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Gurtler JB, Beuchat LR. Inhibition of growth of Enterobacter sakazakii in reconstituted infant formula by the lactoperoxidase system. J Food Prot 2007; 70:2104-10. [PMID: 17900089 DOI: 10.4315/0362-028x-70.9.2104] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Neonatal bacteremia and meningitis caused by the opportunistic pathogen Enterobacter sakazakii have been associated with the consumption of reconstituted powdered infant formula. Lactoperoxidase (LPO), present in mammalian milk, is known to inhibit the growth of enteric pathogens. We undertook a study to determine if the lactoperoxidase system (LPOS) will inhibit the growth of E. sakazakii in a milk-based powdered infant formula reconstituted with water. Initially at 0.04 CFU/ml, E. sakazakii grew to 2.40 to 2.74 log CFU/ml in reconstituted infant formula held at 30 or 37 degrees C for 8 h and to 0.6 log CFU/ ml in formula held for 12 h at 21 degrees C. The pathogen was not detected (less than 1 CFU/227 ml) by enrichment of formula treated with 10 to 30 microg/ml LPO and stored for 24 h at 37 degrees C or 30 microg/ml LPO and stored for 24 h at 30 degrees C. Populations of E. sakazakii, initially at 4.40 log CFU/ml of reconstituted infant formula containing 5 microg/ml LPO, did not increase significantly (P > 0.05) for up to 12 h at 21 and 30 degrees C. Populations either decreased significantly or were unchanged in formula supplemented with 10 microg/ml LPO and stored at 21, 30, or 37 degrees C for up to 24, 8, and 8 h, respectively. Results indicate that LPOS can be used to control the growth of E. sakazakii in reconstituted infant formula, thereby potentially reducing the risk of neonatal infections resulting from consumption of formula that may be contaminated with the pathogen.
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Affiliation(s)
- Joshua B Gurtler
- Center for Food Safety and Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, Georgia 30223-1797, USA
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19
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Ihalin R, Nuutila J, Loimaranta V, Lenander M, Tenovuo J, Lilius EM. Susceptibility of Fusobacterium nucleatum to killing by peroxidase-iodide-hydrogen peroxide combination in buffer solution and in human whole saliva. Anaerobe 2007; 9:23-30. [PMID: 16887684 DOI: 10.1016/s1075-9964(03)00005-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2002] [Revised: 09/20/2002] [Accepted: 12/10/2002] [Indexed: 11/23/2022]
Abstract
Some Gram-negative anaerobic bacteria have been associated with the infection of tooth supporting tissues, i.e. periodontitis. Of these bacteria, Fusobacterium nucleatum is sensitive to lactoperoxidase/myeloperoxidase-iodide-hydrogen peroxide system in vitro, but salivary concentrations of thiocyanate abolishes the bactericidality. These bacteria are located in periodontal pockets, on oral mucosa and in saliva. Although F. nucleatum most probably does not belong to the group of main periodontal pathogens, it sustains its proportion in the periodontal flora when gingivitis progresses to periodontitis. In this study, the sensitivity of F. nucleatum to different horseradish peroxidase-iodide-hydrogen peroxide combinations was tested both in buffer and in sterilized human whole saliva. Horseradish peroxidase was chosen because it does not bind thiocyanate at pH > or = 6. After 1h incubation at 37 degrees C, the cell viability was estimated by plate count and with flow cytometer using LIVE/DEAD BacLight kit (Molecular Probes, USA). In saliva, the horseradish peroxidase (50 microg/mL)-iodide (2.5 mM)-hydrogen peroxide (2.5 mM) combination decreased the amount of viable bacteria to 37% compared to 85% in the control without any of the components when measured with flow cytometer. Replacement of buffer by saliva decreased the bactericidality of the peroxidase system. However, in buffer less iodide and hydrogen peroxide was needed to produce significant decrease in the number of viable bacteria when measured by plate count than with flow cytometer. Our study shows that horseradish peroxidase-iodide-hydrogen peroxide combination is able to kill F. nucleatum cells in saliva. Horseradish peroxidase-iodide-hydrogen peroxide combination may be useful to diminish the degree of re-colonization of periodontitis-associated bacteria after periodontal therapy and to inhibit the transmission of these bacteria via saliva.
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Affiliation(s)
- Riikka Ihalin
- Institute of Dentistry, Turku Immunology Centre and TuBS, University of Turku, Lemminkäisenkatu 2, Fin-20520 Turku, Finland.
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20
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Goi N, Hirai Y, Harada H, Ikari A, Ono T, Kinae N, Hiramatsu M, Nakamura K, Takagi K. COMPARISON OF PEROXIDASE RESPONSE TO MENTAL ARITHMETIC STRESS IN SALIVA OF SMOKERS AND NON-SMOKERS. J Toxicol Sci 2007; 32:121-7. [PMID: 17538236 DOI: 10.2131/jts.32.121] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Saliva is the first body fluid to encounter exogenous materials or gases such as cigarette smoke (CS). The aim of this study was to examine whether smoking affects oral peroxidase (OPO) reactivity to mental stress. The subjects were 39 non-smokers and 10 smokers. In the experiment, the Kraepelin psychodiagnostic test as a psychological stressor and saliva was sampled 30 min before, just before, immediately after, and 30 min after the beginning of the test. OPO reactivity to the test between smokers and non-smokers was measured in addition to uric acid concentration, flow rate, IgA, thiocyanate (SCN-) concentration, amylase activity as a salivary stress marker, and ultra-weak chemiluminescence (UCL) level, which is indicative of salivary antioxidative and antibacterial abilities. Moreover, we studied the effect of smoking on the response of salivary peroxidase (SPO) and myeloperoxidase (MPO) activity to mental stress, respectively. The results showed that the IgA concentration, amylase activity, SCN(- concentration, and UCL level are higher in the non-smoking group than smoking group and the IgA concentration and UCL level increased in the non-smokers significantly just after the Kraepelin test. The levels of SCN-) were higher in smokers than in non-smokers and OPO activity was greater in the non-smoking group in all sessions. Furthermore, only the non-smokers had significantly increased MPO activity just after the test. MPO may play a crucial role in the response to acute psychological stress besides inflammation, and CS suppresses this response significantly.
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Affiliation(s)
- Nobuhiro Goi
- Department of Environmental Biochemistry and Toxicology, University of Shizuoka School of Pharmaceutical Science, Yada, Shizuoka, Japan
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21
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Conner GE, Wijkstrom-Frei C, Randell SH, Fernandez VE, Salathe M. The lactoperoxidase system links anion transport to host defense in cystic fibrosis. FEBS Lett 2006; 581:271-8. [PMID: 17204267 PMCID: PMC1851694 DOI: 10.1016/j.febslet.2006.12.025] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Revised: 12/06/2006] [Accepted: 12/11/2006] [Indexed: 12/20/2022]
Abstract
Chronic respiratory infections in cystic fibrosis result from CFTR channel mutations but how these impair antibacterial defense is less clear. Airway host defense depends on lactoperoxidase (LPO) that requires thiocyanate (SCN-) to function and epithelia use CFTR to concentrate SCN- at the apical surface. To test whether CFTR mutations result in impaired LPO-mediated host defense, CF epithelial SCN- transport was measured. CF epithelia had significantly lower transport rates and did not accumulate SCN- in the apical compartment. The lower CF [SCN-] did not support LPO antibacterial activity. Modeling of airway LPO activity suggested that reduced transport impairs LPO-mediated defense and cannot be compensated by LPO or H2O2 upregulation.
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Affiliation(s)
- Gregory E Conner
- Division of Pulmonary and Critical Care Medicine, University of Miami School of Medicine, Miami, FL 33136, United States.
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22
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Ihalin R, Loimaranta V, Tenovuo J. Origin, structure, and biological activities of peroxidases in human saliva. Arch Biochem Biophys 2006; 445:261-8. [PMID: 16111647 DOI: 10.1016/j.abb.2005.07.004] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Revised: 07/04/2005] [Accepted: 07/10/2005] [Indexed: 11/23/2022]
Abstract
Human whole saliva contains two peroxidases, salivary peroxidase (hSPO) and myeloperoxidase (hMPO), which are part of the innate host defence in oral cavity. Both hSPO as well as human milk lactoperoxidase (hLPO) are coded by the same gene, but to what extent the different producing glands, salivary and mammary glands, affect the final conformation of the enzymes is not known. In human saliva the major function of hSPO and hMPO is to catalyze the oxidation of thiocyanate (SCN(-)) in the presence of hydrogen peroxide (H(2)O(2)) resulting in end products of wide antimicrobial potential. In addition cytotoxic H(2)O(2) is degraded. Similar peroxidation reactions inactivate some mutagenic and carcinogenic compounds, which suggests another protective mechanism of peroxidases in human saliva. Although being target of an active antimicrobial research, the structure-function relationships of hSPO are poorly known. However, recently published method for recombinant hSPO production offers new tools for those investigations.
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Affiliation(s)
- Riikka Ihalin
- Department of Cariology, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, FIN-20520 Turku, Finland
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23
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Seifu E, Buys EM, Donkin E. Significance of the lactoperoxidase system in the dairy industry and its potential applications: a review. Trends Food Sci Technol 2005. [DOI: 10.1016/j.tifs.2004.11.002] [Citation(s) in RCA: 202] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Touch V, Hayakawa S, Yamada S, Kaneko S. Effects of a lactoperoxidase–thiocyanate–hydrogen peroxide system on Salmonella enteritidis in animal or vegetable foods. Int J Food Microbiol 2004; 93:175-83. [PMID: 15135956 DOI: 10.1016/j.ijfoodmicro.2003.11.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2003] [Revised: 10/08/2003] [Accepted: 11/11/2003] [Indexed: 11/18/2022]
Abstract
Lactoperoxidase (LPO) from skim milk was purified by ion-exchange chromatography. The purified protein was used to catalyze the oxidation of thiocyanate by H2O2 in an antibacterial system (LPO system). The LPO system was used to inactivate or inhibit Salmonella enteritidis in tomato juice, carrot juice, milk, liquid whole egg, and chicken skin extract under various conditions. The system was found to be more effective against the organism in vegetable juices than in animal products, at low pH than at neutral pH, and at higher temperatures than at lower temperatures. Acid-adapted S. enteritidis cells were more susceptible than nonadapted cells. The system reduced numbers of S. enteritidis in vegetable products by up to 5.4 log units and inhibited growth of the organism in animal-derived foods during 4 h incubation at 30 degrees C. Sodium chloride (>100 mM) and polyphosphate (0.01-0.5%) enhanced the antibacterial effects of the system in tomato juice and chicken skin extract, respectively. The findings indicate that the LPO system could probably be used to prevent the growth and survival of salmonellae in minimally processed fruit and vegetable products, but combination of the system with other preservatives or treatments would be needed to effectively inhibit growth and survival of salmonellae in animal products.
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Affiliation(s)
- Visalsok Touch
- Department of Biochemistry and Food Science, Faculty of Agriculture, Kagawa University, Ikenobe, Kagawa, Japan
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25
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Wijkstrom-Frei C, El-Chemaly S, Ali-Rachedi R, Gerson C, Cobas MA, Forteza R, Salathe M, Conner GE. Lactoperoxidase and human airway host defense. Am J Respir Cell Mol Biol 2003; 29:206-12. [PMID: 12626341 DOI: 10.1165/rcmb.2002-0152oc] [Citation(s) in RCA: 154] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The lactoperoxidase (LPO) antibiotic system is a well-characterized component of mammary and salivary gland secretions. Because LPO has been shown to function in ovine airways, human airway tissue and secretions were examined for the presence of LPO and its substrate, the anion thiocyanate (SCN-). In addition, human airway secretions were tested for LPO-mediated antibacterial activity, and LPO's activity was assessed against some human airway pathogens. The data showed that normal human airway secretions contained LPO enzyme activity (0.65 +/- 0.09 microg/mg secreted protein; n = 17), and Western blots of secretions demonstrated bands of the expected sizes for LPO. LPO mRNA was detected in trachea by sequencing PCR-amplified cDNA. SCN-, LPO's substrate, was present in undiluted airway secretions at concentrations sufficient for LPO catalysis (0.46 +/- 0.19 mM; n = 8), and diluted secretions contained antibacterial activity with LPO-like properties. Immunocytochemistry localized LPO to submucosal glands in human bronchi. Finally, as expected based on the known antibacterial spectrum of the LPO system, airway secretions showed LPO-dependent activity against Pseudomonas aeruginosa. In addition, the airway LPO system was shown to be effective against Burkholderia cepacia and Haemophilus influenzae. Thus, a functional LPO system exists in human airways and may contribute to airway host defense against infection.
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Affiliation(s)
- Corinne Wijkstrom-Frei
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Miami School of Medicine, Miami, FL 33101, USA
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Hughes R, Andrew PW, Kilvington S. Enhanced killing of Acanthamoeba cysts with a plant peroxidase-hydrogen peroxide-halide antimicrobial system. Appl Environ Microbiol 2003; 69:2563-7. [PMID: 12732522 PMCID: PMC154507 DOI: 10.1128/aem.69.5.2563-2567.2003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The activity of H(2)O(2) against the resistant cyst stage of the pathogenic free-living amoeba Acanthamoeba was enhanced by the addition of KI and either horseradish peroxidase or soybean peroxidase or, to a lesser degree, lactoperoxidase. This resulted in an increase in the cysticidal activity of 3% (wt/vol) H(2)O(2), and there was >3-log killing in 2 h, compared with the 6 h required for comparable results with the peroxide solution alone (P < 0.05). With 2% H(2)O(2), enhancement was observed at all time points (P < 0.05), and total killing of the cyst inoculum occurred at 4 h, compared with 6 h for the peroxide alone. The activity of sublethal 1% H(2)O(2) was enhanced to give 3-log killing after 8 h of exposure (P < 0.05). No enhancement was obtained when KCl or catalase was used as a substitute in the reaction mixtures. The H(2)O(2) was not neutralized in the enhanced system during the experiments. However, in the presence of a platinum disk used to neutralize H(2)O(2) in contact lens care systems, the enhanced 2% H(2)O(2) system gave 2.8-log killing after 6 h or total cyst killing by 8 h, and total neutralization of the H(2)O(2) occurred by 4 h. In contrast, 2% H(2)O(2) alone resulted in <0.8-log killing of cysts in the presence of the platinum disk due to rapid (<1 h) neutralization of the peroxide. Our observations could result in significant improvement in the efficacy of H(2)O(2) contact lens disinfection systems against Acanthamoeba cysts and prevention of acanthamoeba keratitis.
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Affiliation(s)
- Reanne Hughes
- Department of Microbiology and Immunology, University of Leicester, Leicester LE1 9HN, United Kingdom
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27
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Shin K, Hayasawa H, Lönnerdal B. Inhibition of Escherichia coli respiratory enzymes by the lactoperoxidase-hydrogen peroxide-thiocyanate antimicrobial system. J Appl Microbiol 2001; 90:489-93. [PMID: 11309058 DOI: 10.1046/j.1365-2672.2001.01268.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS The lactoperoxidase-hydrogen peroxide-thiocyanate antimicrobial system (LPAS) is known to inhibit bacterial respiration. In the present study, several respiratory enzymes of Escherichia coli were compared in terms of their susceptibility to the LPAS. METHODS AND RESULTS Exposure of E. coli to the LPAS, upon which 99.6% of the bacteria were killed, resulted in the following percentage of inactivation of substrate-specific membrane oxidases: succinate (94.2%) > NADH (84.6%) > glycerol-3-phosphate (67.8%) > DL-lactate (64.1%). With the same treatment, substrate-specific membrane dehydrogenases were inactivated as follows: succinate (99.1%) > DL-lactate (53.8%) > glycerol-3-phosphate (45.0%) > NADH (36.8%). Terminal oxidase, however, measured using a ubiquinone analogue (2,3-dimethoxy-5-methyl-6-decyl-1,4-benzoquinone) after reduction, was only 21.4% inactivated by the LPAS. CONCLUSION These data suggest that dehydrogenases are the primary targets of the LPAS in the respiratory chain of E. coli. SIGNIFICANCE AND IMPACT OF THE STUDY This study has determined for the first time the primary targets of LPAS in the bacterial respiratory chain.
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Affiliation(s)
- K Shin
- Nutritional Science Laboratory, Morinaga Milk Industry Co. Ltd, Kanagawa, Japan
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28
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Abstract
Bacillus cereus is a causative agent in both gastrointestinal and in nongastrointestinal infections. Enterotoxins, emetic toxin (cereulide), hemolysins, and phoshpolipase C as well as many enzymes such as beta-lactamases, proteases and collagenases are known as potential virulence factors of B. cereus. A special surface structure of B. cereus cells, the S-layer, has a significant role in the adhesion to host cells, in phagocytosis and in increased radiation resistance. Interest in B. cereus has been growing lately because it seems that B. cereus-related diseases, in particular food poisonings, are growing in number.
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Affiliation(s)
- A Kotiranta
- Institute of Dentistry, P.O. Box 41, FIN-00014, University of Helsinki, Helsinki, Finland
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29
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Ihalin R, Loimaranta V, Lenander-Lumikari M, Tenovuo J. The effects of different (pseudo)halide substrates on peroxidase-mediated killing of Actinobacillus actinomycetemcomitans. J Periodontal Res 1998; 33:421-7. [PMID: 9842507 DOI: 10.1111/j.1600-0765.1998.tb02338.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Actinobacillus actinomycetemcomitans is a Gram-negative bacterium which has an important role in localized juvenile and in progressive periodontitis. It is sensitive to killing by the myeloperoxidase (MP)-hydrogen peroxide (H2O2)-chloride system which is part of the innate host defense mediated by polymorphonuclear leukocytes. Since it has been recently suggested that thiocyanate, instead of chloride, could serve as a main substrate for MP as for lactoperoxidase (LP) and salivary peroxidase, we investigated in this study the effect of both LP and MP systems on A. actinomycetemcomitans with different (pseudo)halide substrates, thiocyanate, chloride and iodide. The concentrations of the substrates were physiological for oral fluids, as was the concentration range of H2O2. Both peroxidases produced end products with identical antibacterial activity with thiocyanate and iodide. The oxidation of iodide resulted in the highest antimicrobial efficiency followed by chloride and thiocyanate. Addition of thiocyanate into either MP-H2O2-chloride or MP/LP-H2O2-iodide system abolished the bactericidal activity of the oxidized halide. However, the chloride did not affect the bactericidality of the MP-H2O2-iodide system, but when all 3 (pseudo)halide substrates were present no antimicrobial effect was recorded. Our study shows that the presence of thiocyanate in physiological amounts is able to prevent the bactericidal activity of halide-peroxidase systems in low H2O2 concentrations. These results explain why thiocyanate-peroxidase systems of either innate origin (saliva, crevicular fluid) or introduced by commercial oral hygiene products are most probably ineffective against A. actinomycetemcomitans in vivo. Further studies of halide/thiocyanate ratio are needed to develop products which are also effective against oral anaerobes.
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Affiliation(s)
- R Ihalin
- Institute of Dentistry, University of Turku, Finland
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30
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Abstract
Human saliva contains a number of physical physicochemical, and chemical agents that protect oral tissues against noxious compounds, in particular those produced by various microorganisms. Among such protective factors, the flushing effect of saliva flow is the most important one, not only because it so effectively removes exogenous and endogenous microorganisms and their products into the gut but also because a steady supply of saliva guarantees continuous presence of both non-immune and immune factors in the mouth. A great number of studies with controversial results have been published regarding various individual agents and their possible association to oral health, particularly to dental caries. It appears that no single chemical agent is far more important than the others. For example, patients with selective IgA deficiency have normal levels of non-immune defense factors and often display a compensatory increase in the other immunoglobulin isotypes. The concerted action of all agents in whole saliva, both saliva- and serum-derived, provides a multifunctional protective network that is collapsed only if salivary flow rate is substantially reduced. In this mixture of defense factors, many show additive or even synergistic interactions against oral pathogens. Increased knowledge of the molecular functions of various agents has made it possible to prepare oral hygiene product that include host-derived antimicrobial agents instead of synthetic agents. Although the clinical efficacy of such products is still unsatisfactory and poorly described, new technologies, for example in the production of specific antibodies against oral pathogens, may considerably improve the antimicrobial power of these products.
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Affiliation(s)
- J Tenovuo
- Institute of Dentistry and Turku Immunology Centre, University of Turku, Finland
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31
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Tenovuo J, Anttilla O, Lumikari M, Sievers G. Antibacterial effect of myeloperoxidase against Streptococcus mutans. ORAL MICROBIOLOGY AND IMMUNOLOGY 1988; 3:68-71. [PMID: 2855860 DOI: 10.1111/j.1399-302x.1988.tb00084.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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