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Upoma N, Akter N, Ferdousi FK, Sultan MZ, Rahman S, Alodhayb A, Alibrahim KA, Habib A. Interactions of Co(II)- and Zn(II)porphyrin of 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin with DNA in Aqueous Solution and Their Antimicrobial Activities. ACS OMEGA 2024; 9:22325-22335. [PMID: 38799349 PMCID: PMC11112571 DOI: 10.1021/acsomega.4c01708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/31/2024] [Accepted: 04/25/2024] [Indexed: 05/29/2024]
Abstract
Antibiotics are frequently used to treat, prevent, or control bacterial infections, but in recent years, infections resistant to all known classes of conventional antibiotics have significantly grown. The development of novel, nontoxic, and nonincursive antimicrobial methods that work more quickly and efficiently than the present antibiotics is required to combat this growing public health issue. Here, Co(II) and Zn(II) derivatives of tetrakis(1-methylpyridinium-4yl)porphyrin [H2TMPyP]4+ as a tetra(ρ-toluenesulfonate) were synthesized and purified to investigate their interactions with DNA (pH 7.40, 25 °C) using UV-vis, fluorescence techniques, and antimicrobial activity. UV-vis results showed that [H2TMPyP]4+ had a high hypochromicity (∼64%) and a substantial bathochromic shift (Δλ, 14 nm), while [Co(II)TMPyP]4+ and [Zn(II)TMPyP]4+ showed little hypochromicity (∼37%) and a small bathochromic shift (Δλ, 3-6 nm). Results reveal that [H2TMPyP]4+ interacts with DNA via intercalation, while Co(II)- and [Zn(II)TMPyP]4+ interact with DNA via outside self-stacking. Fluorescence results also confirmed the interaction of [H2TMPyP]4+ and the metalloporphyrins with DNA. Results of the antimicrobial activity assay revealed that the metalloporphyrins showed inhibitory effects on Gram-positive and Gram-negative bacteria and fungi, but that neither the counterions nor [H2TMPyP]4+ exhibited any inhibitory effects. Mechanism of antimicrobial activities of metalloporphyrins are discussed.
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Affiliation(s)
| | - Nazmin Akter
- Department
of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
| | | | - Md. Zakir Sultan
- Centre
for Advanced Research in Sciences (CARS), University of Dhaka, Dhaka 1000, Bangladesh
| | - Shofiur Rahman
- Biological
and Environmental Sensing Research Unit, King Abdullah Institute for
Nanotechnology, King Saud University, Riyadh 11451, Saudi Arabia
| | - Abdullah Alodhayb
- Biological
and Environmental Sensing Research Unit, King Abdullah Institute for
Nanotechnology, King Saud University, Riyadh 11451, Saudi Arabia
| | - Khuloud A. Alibrahim
- Department
of Chemistry, College of Science, Princess
Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia
| | - Ahsan Habib
- Department
of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
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2
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Hu O, Li Z, He Q, Tong Y, Tan Y, Chen Z. Fluorescence Biosensor for One-Step Simultaneous Detection of Mycobacterium tuberculosis Multidrug-Resistant Genes Using nanoCoTPyP and Double Quantum Dots. Anal Chem 2022; 94:7918-7927. [PMID: 35594337 DOI: 10.1021/acs.analchem.2c00723] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The diagnosis of multidrug-resistant tuberculosis (MDR-TB) is crucial for the subsequent drug guidance to improve therapy and control the spread of this infectious disease. Herein, we developed a novel florescence biosensor for simultaneous detection of Mycobacterium tuberculosis (Mtb) multidrug-resistant genes (rpoB531 for rifampicin and katG315 for isoniazid) by using our synthesized nanocobalt 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (nanoCoTPyP) and double quantum dots (QDs). Several nanoCoTPyPs with different charges and morphology were successfully prepared via the surfactant-assisted method and their quenching ability and restoring efficiency for DNA detection were systematically analyzed. It was found that spherical nanoCoTPyP with positive charge exhibited excellent quenching effect and sensing performance for the two DNAs' detection due to its affinity differences towards single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA). ssDNA attached on QDs (QDs-ssDNA) was specifically hybridized with targets to form QDs-dsDNA, resulting in fluorescence recovery due to the disruption of the interactions between nanoCoTPyP and ssDNA. Two drug-resistant genes could be simultaneously quantified in a single run and relatively low limits of detection (LODs) were obtained (24 pM for T1 and 20 pM for T2). Furthermore, the accuracy and reliability of our method were verified by testing clinical samples. This simple and low-cost approach had great potential to be applied in clinical diagnosis of MDR-TB.
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Affiliation(s)
- Ou Hu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Zeyu Li
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Qidi He
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Yanli Tong
- Guangdong Second Provincial General Hospital, Guangzhou 510317, P. R. China
| | - Yaoju Tan
- State Key Laboratory of Respiratory Disease, Department of Clinical Laboratory, Guangzhou Chest Hospital, Guangzhou 510095, P. R. China
| | - Zuanguang Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
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3
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Araujo-Chaves JC, Miranda ÉGA, Lopes DM, Yokomizo CH, Carvalho-Jr WM, Nantes-Cardoso IL. Antioxidant cytochrome c-like activity of para-Mn (III)TMPyP. Biochimie 2021; 184:116-124. [PMID: 33662439 DOI: 10.1016/j.biochi.2021.02.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/12/2021] [Accepted: 02/24/2021] [Indexed: 10/22/2022]
Abstract
Manganese porphyrins are well-known protectors against the deleterious effects of pro-oxidant species such as superoxide ions and hydrogen peroxide. The present study investigated the antioxidant cytochrome c-like activities of Mn(III)TMPyP [meso-tetrakis (4-N-methyl pyridinium) porphyrin] against superoxide ion and hydrogen peroxide that remained unexplored for this porphyrin. The association of TMPyP with a model of the inner mitochondrial membrane, cardiolipin (CL)-containing liposomes, shifted +30 mV vs. NHE (normal hydrogen electrode) redox potential of the Mn(II)/Mn(III) redox couple. In CL-containing liposomes, Mn(III)TMPyP was reduced by superoxide ions and recycled by Fe(III)cytochrome c to the oxidized form. Similarly, isolated rat liver mitoplasts added to a sample of Mn(II)TMPyP promoted immediate porphyrin reoxidation by electron transfer to the respiratory chain. These results show that Mn(III)TMPyP can act as an additional pool of Fe(III)cytochrome c capable of transferring electrons that escape from the IV complex back into the respiratory chain. Unlike Fe(II)cytochrome c, Mn(II)TMPyP was not efficient for hydrogen peroxide clearance. Therefore, by reducing cytochrome c, Mn(II)TMPyP can indirectly contribute to hydrogen peroxide elimination.
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Affiliation(s)
- Juliana C Araujo-Chaves
- Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, Zip Code 09210-580, Brazil
| | - Érica G A Miranda
- Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, Zip Code 09210-580, Brazil
| | - David M Lopes
- Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, Zip Code 09210-580, Brazil
| | - César H Yokomizo
- Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, Zip Code 09210-580, Brazil
| | - Waldemir M Carvalho-Jr
- Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, Zip Code 09210-580, Brazil
| | - Iseli L Nantes-Cardoso
- Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, Zip Code 09210-580, Brazil.
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4
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Rational engineering of semiconductor QDs enabling remarkable 1 O 2 production for tumor-targeted photodynamic therapy. Biomaterials 2017; 148:31-40. [DOI: 10.1016/j.biomaterials.2017.09.026] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/18/2017] [Accepted: 09/19/2017] [Indexed: 12/23/2022]
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Skwor TA, Klemm S, Zhang H, Schardt B, Blaszczyk S, Bork MA. Photodynamic inactivation of methicillin-resistant Staphylococcus aureus and Escherichia coli: A metalloporphyrin comparison. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 165:51-57. [DOI: 10.1016/j.jphotobiol.2016.10.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/10/2016] [Accepted: 10/14/2016] [Indexed: 12/18/2022]
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Overall biochemical changes in bacteria photosensitized with cationic porphyrins monitored by infrared spectroscopy. Future Med Chem 2016; 8:613-28. [PMID: 27073984 DOI: 10.4155/fmc-2015-0008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Photodynamic inactivation of micro-organisms is a promising nonantibiotic multitarget approach to treat localized and superficial infections through oxidative stress. Herein, the changes occurring on major cellular components of Escherichia coli and Staphylococcus warneri, induced by photosensitization with cationic porphyrins (Tri-Py(+)-Me-PF and Tetra-Py(+)-Me) and white light, were monitored by infrared spectroscopy. RESULTS In E. coli, most of the changes occurred on proteins and lipids, suggesting a key effect on lipopolysaccharides in the first irradiation times. In S. warneri, proteins were the major molecular targets of oxidative damage but phospholipids and polysaccharides were also affected. CONCLUSION Infrared spectroscopy is a very interesting tool to monitor biochemical changes induced by photosensitization in bacteria and also to infer on its mechanism of action.
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Rivero Berti I, Dell' Arciprete ML, Dittler ML, Miñan A, Fernández Lorenzo de Mele M, Gonzalez M. Delivery of fluorophores by calcium phosphate-coated nanoliposomes and interaction with Staphylococcus aureus biofilms. Colloids Surf B Biointerfaces 2016; 142:214-222. [PMID: 26954088 DOI: 10.1016/j.colsurfb.2016.03.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/22/2016] [Accepted: 03/01/2016] [Indexed: 01/09/2023]
Abstract
The delivery capacity and mechanical stability of calcium phosphate (CaP) coated 1,2-dioleoyl-sn-glycero-3-phosphate (DOPA) liposomes free and adsorbed on bacterial surface was investigated introducing either acridine orange (AO) or 5,10,15,20-Tetrakis(1-methyl-4-pyridinio)porphyrin (TMP) in the aqueous core of the liposomes. The obtained nanomaterials were thoroughly characterized by electron and optical microscopy and by fluorescence techniques. Distribution of the AO and TMP molecules between the aqueous liposomes core and the outer solution was demonstrated by the band shifts and broadening of the excitation-emission matrices and the modified Stern-Volmer model for fluorescence quenching. In aqueous suspensions, c.a. 40% of AO was released to the outer solution while only a small percentage of TMP was observed to reach the outer liposome surface. The nanoliposomes adhesion capacity and the leaking of fluorophore molecules to Staphylococcus aureus (S. aureus) biofilms were further evaluated. A close interaction between liposomes and S. aureus biofilm was evidenced by TEM and SEM imaging. Epifluorescence experiments demonstrated that CaP-coated liposomes have good biofilm staining capability after two hours incubation of the biofilms with the liposomes, thus supporting an important release of the fluorophores when in contact with the biofilm. Altogether, the obtained results strongly suggest that CaP-coated liposomes are capable of activating drug release when in presence of S. aureus biofilms and smears. The studies herein presented, indicate that CaP-coated liposomes are potential vehicles for the selective delivery of drugs to S. aureus biofilms, as is the case of the singlet oxygen photosensitizer TMP, a well known photodynamic antibacterial agent.
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Affiliation(s)
- Ignacio Rivero Berti
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Casilla de Correo 16, Sucursal 4, 1900 La Plata Argentina
| | - María Laura Dell' Arciprete
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Casilla de Correo 16, Sucursal 4, 1900 La Plata Argentina.
| | - María Laura Dittler
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Casilla de Correo 16, Sucursal 4, 1900 La Plata Argentina
| | - Alejandro Miñan
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Casilla de Correo 16, Sucursal 4, 1900 La Plata Argentina
| | - Mónica Fernández Lorenzo de Mele
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Casilla de Correo 16, Sucursal 4, 1900 La Plata Argentina
| | - Mónica Gonzalez
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Casilla de Correo 16, Sucursal 4, 1900 La Plata Argentina
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Thomas M, Craik JD, Tovmasyan A, Batinic-Haberle I, Benov LT. Amphiphilic cationic Zn-porphyrins with high photodynamic antimicrobial activity. Future Microbiol 2016; 10:709-24. [PMID: 26000647 DOI: 10.2217/fmb.14.148] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
AIM Photodynamic inactivation of microbes can efficiently eradicate antibiotic-resistant strains. Systematic structural modification was used to investigate how porphyrin-based photosensitizers (PSs) could be designed for improved antibacterial activity. MATERIALS & METHODS Zinc(II)5,10,15,20-tetrakis(N-alkylpyridinium-2(3,4)-yl)porphyrins presenting systematic modifications at the periphery of the porphyrin ring were evaluated for toxicity and antimicrobial photodynamic activity by measuring metabolic activity, cell membrane integrity and viability using antibiotic-sensitive and resistant Escherichia coli strains as model Gram-negative targets. RESULTS Maximal sensitizer uptake, and, upon illumination, decrease of viable bacteria by >6 log10 were achieved by positively charged amphiphilic PSs with longer (six to eight carbon) alkyl substituents. CONCLUSION Antibacterial photoefficiency (throughout the text photoefficiency has been used as equivalent of photocytotoxic efficacy) can be increased by orders of magnitude by increasing the lipophilicity of cationic alkylmetalloporphyrin PSs.
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Affiliation(s)
- Milini Thomas
- 1Department of Biochemistry, Faculty of Medicine, Kuwait University, PO Box 24923, Safat 13110, Kuwait
| | - James D Craik
- 1Department of Biochemistry, Faculty of Medicine, Kuwait University, PO Box 24923, Safat 13110, Kuwait
| | - Artak Tovmasyan
- 2Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ines Batinic-Haberle
- 2Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ludmil T Benov
- 1Department of Biochemistry, Faculty of Medicine, Kuwait University, PO Box 24923, Safat 13110, Kuwait
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9
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Parambath M, Hanley QS, Martin-Martinez FJ, Giesa T, Buehler MJ, Perry CC. The nature of the silicaphilic fluorescence of PDMPO. Phys Chem Chem Phys 2016; 18:5938-48. [DOI: 10.1039/c5cp05105c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Interactions with silica moderates the fluorescence behaviour of PDMPO.
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Affiliation(s)
- Mithun Parambath
- School of Science and Technology
- Nottingham Trent University
- Nottingham
- UK
| | - Quentin S. Hanley
- School of Science and Technology
- Nottingham Trent University
- Nottingham
- UK
| | | | - Tristan Giesa
- Department of Civil and Environmental Engineering
- Massachusetts Institute of Technology
- USA
| | - Markus J. Buehler
- Department of Civil and Environmental Engineering
- Massachusetts Institute of Technology
- USA
| | - Carole C. Perry
- School of Science and Technology
- Nottingham Trent University
- Nottingham
- UK
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10
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Pradines V, Bijani C, Stigliani JL, Blanzat M, Rico-Lattes I, Pratviel G. Cationic Porphyrin-Anionic Surfactant Mixtures for the Promotion of Self-Organized 1:4 Ion Pairs in Water with Strong Aggregation Properties. Chemphyschem 2015; 16:3877-85. [PMID: 26456707 DOI: 10.1002/cphc.201500783] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Indexed: 12/21/2022]
Abstract
We performed a systematic study on the spectroscopic and aggregation properties of stoichiometric mixtures (1:4) of the tetracationic meso-tetrakis(4-N-methylpyridinium)porphyrin (H2 TMPyP) and three sodium alkylsulfate surfactants (tetradecyl, hexadecyl, and octadecylsulfate) in an aqueous solution. The objective was to build a supramolecular aggregate, which would favor the internalization of tetracationic porphyrins in cells without chemical modification of the structure of the porphyrin. We show that stoichiometric H2 TMPyP/alkylsulfate (1:4) mixtures lead to the formation of large hollow spherical aggregates (60-160 nm). The TEM images show that the membrane of these aggregates are composed of smaller aggregates, which are probably rod-like micelles. These rod-like micelles have a hydrophobic core composed of the alkyl chains of the alkylsulfate surfactant, whereas the charged surface corresponds to the tetracationic porphyrins.
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Affiliation(s)
- Vincent Pradines
- Laboratoire de Chimie de Coordination CNRS, UPR 8241, 205 route de Narbonne, BP 44099, 31077, Toulouse cedex 4, France.,Université de Toulouse, Université Paul Sabatier UPS, INPT, Toulouse, France
| | - Christian Bijani
- Laboratoire de Chimie de Coordination CNRS, UPR 8241, 205 route de Narbonne, BP 44099, 31077, Toulouse cedex 4, France.,Université de Toulouse, Université Paul Sabatier UPS, INPT, Toulouse, France
| | - Jean-Luc Stigliani
- Laboratoire de Chimie de Coordination CNRS, UPR 8241, 205 route de Narbonne, BP 44099, 31077, Toulouse cedex 4, France.,Université de Toulouse, Université Paul Sabatier UPS, INPT, Toulouse, France
| | - Muriel Blanzat
- Laboratoire des Interactions Moléculaires et Réactivité Chimique et Photochimique, UMR 5623 CNRS, 118 route de Narbonne, 31062, Toulouse cedex 9, France.,Université de Toulouse, Université Paul Sabatier UPS, INPT, Toulouse, France
| | - Isabelle Rico-Lattes
- Laboratoire des Interactions Moléculaires et Réactivité Chimique et Photochimique, UMR 5623 CNRS, 118 route de Narbonne, 31062, Toulouse cedex 9, France.,Université de Toulouse, Université Paul Sabatier UPS, INPT, Toulouse, France
| | - Geneviève Pratviel
- Laboratoire de Chimie de Coordination CNRS, UPR 8241, 205 route de Narbonne, BP 44099, 31077, Toulouse cedex 4, France.,Université de Toulouse, Université Paul Sabatier UPS, INPT, Toulouse, France
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Abstract
The emergence of microbial resistance is becoming a global problem in clinical and environmental areas. As such, the development of drugs with novel modes of action will be vital to meet the threats created by the rise in microbial resistance. Microbial photodynamic inactivation is receiving considerable attention for its potentialities as a new antimicrobial treatment. This review addresses the interactions between photosensitizers and bacterial cells (binding site and cellular localization), the ultrastructural, morphological and functional changes observed at initial stages and during the course of photodynamic inactivation, the oxidative alterations in specific molecular targets, and a possible development of resistance.
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Kawai C, Araújo-Chaves JC, Magrini T, Sanches COCC, Pinto SMS, Martinho H, Daghastanli N, Nantes IL. Photodamage in a mitochondrial membrane model modulated by the topology of cationic and anionic meso-tetrakis porphyrin free bases. Photochem Photobiol 2014; 90:596-608. [PMID: 24351019 DOI: 10.1111/php.12228] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 12/09/2013] [Indexed: 11/30/2022]
Abstract
The photodynamic effects of the cationic TMPyP (meso-tetrakis [N-methyl-4-pyridyl]porphyrin) and the anionic TPPS4 (meso-tetrakis[4-sulfonatophenyl]porphyrin) against PC/CL phosphatidylcholine/cardiolipin (85/15%) membranes were probed to address the influence of phorphyrin binding on lipid damage. Electronic absorption spectroscopy and zeta potential measurements demonstrated that only TMPyP binds to PC/CL large unilamellar vesicles (LUVs). The photodamage after irradiation with visible light was analyzed by dosages of lipid peroxides (LOOH) and thiobarbituric reactive substance and by a contrast phase image of the giant unilamellar vesicles (GUVs). Damage to LUVs and GUVs promoted by TMPyP and TPPS4 were qualitatively and quantitatively different. The cationic porphyrin promoted damage more extensive and faster. The increase in LOOH was higher in the presence of D2O, and was impaired by sodium azide and sorbic acid. The effect of D2O was higher for TPPS4 as the photosensitizer. The use of DCFH demonstrated that liposomes prevent the photobleaching of TMPyP. The results are consistent with a more stable TMPyP that generates long-lived singlet oxygen preferentially partitioned in the bilayer. Conversely, TPPS4 generates singlet oxygen in the bulk whose lifetime is increased in D2O. Therefore, the affinity of the porphyrin to the membrane modulates the rate, type and degree of lipid damage.
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Affiliation(s)
- Cintia Kawai
- Centro de Ciências Naturais e Humanas (CCNH), Universidade Federal do ABC, Santo André, SP, Brazil
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