scholarly journals Mechanisms of photodynamic inactivation of acridine orange-sensitized transfer RNA : Participation of singlet oxygen and base damage leading to inactivation.

1986 ◽  
Vol 27 (4) ◽  
pp. 339-351 ◽  
Author(s):  
JUMPEI AMAGASA
Keyword(s):  
Singlet Oxygen ◽  
Acridine Orange ◽  
Transfer Rna ◽  
Photodynamic Inactivation ◽  
Base Damage

On the Mechanism of the Acridine Orange Sensitized Photodynamic Inactivation of Lysozyme

1976 ◽  
Vol 31 (1-2) ◽  
pp. 29-39 ◽  
Author(s):  
Peter Rosenkranz ◽  
I. Basic Kinetics ◽  
Hartmut Schmidt
Keyword(s):  
Singlet Oxygen ◽  
Acridine Orange ◽  
Ph Value ◽  
Photodynamic Inactivation ◽  
Rate Process ◽  
First Order ◽  
Quenching Process ◽  
Pseudo First Order ◽  
Kinetics Of ◽  
Excited Oxygen

The kinetics of the photodynamic desactivation of lysozyme in presence of acridine orange as the sensitizer have been investigated in detail varying oxygen, protein, dye concentration, ionic strength and pH value. The kinetics can be approximately described as an over all pseudo-first- order rate process. Changing the solvent from water to D2O or by quenching experiments in pres­ence of azide ions it could be shown that the desactivation of lysozyme is caused exclusively by singlet oxygen. The excited oxygen occurs via the triplet state of the dye with a rate constant considerably lower than that to be expected for a diffusionally controlled reaction. Singlet oxygen reacts chemically (desactivation, k=2.9 × 107 ᴍ-1 sec-1) and physically (quenching process, k = 4.1 × 108 ᴍ-1sec-1) with the enzyme. The kinetical analysis shows that additional chemical reactions between singlet oxygen and lysozyme would have only little influence on the kinetics of the desactivation as long as their products would be enzymatically active and their kinetical constants would be less than about 1 × 108 ᴍ-1 sec-1.

scholarly journals Binding of acridine orange to transfer RNA and photodynamic inactivation.

1986 ◽  
Vol 27 (4) ◽  
pp. 325-338 ◽  
Author(s):  
JUMPEI AMAGASA
Keyword(s):  
Acridine Orange ◽  
Transfer Rna ◽  
Photodynamic Inactivation

On the Mechanism of the Acridine Orange Sensitized Photodynamic Inactivation of Lysozyme II. Kinetics in Presence of N-Acetylglucosamine

1976 ◽  
Vol 31 (11-12) ◽  
pp. 679-682 ◽  
Author(s):  
Peter Rosenkranz ◽  
Hartmut Schmidt
Keyword(s):  
Amino Acid ◽  
Triplet State ◽  
Singlet Oxygen ◽  
Acridine Orange ◽  
Rate Constant ◽  
Enzymatic Reaction ◽  
Photodynamic Inactivation ◽  
Tryptophan Residues ◽  
Amino Acid Side Chains ◽  
Kinetics Of

Abstract The photodynamic deactivation of lysozyme in presence of acridine orange is caused by a reaction between singlet oxygen formed via the dye triplet state and the protein. In order to identify the region where the singlet oxygen reacts with the protein we have investigated the kinetics of the deactivation in presence of the inhibitor of the enzymatic reaction N-acetylglucosamine (GlcNAc). The overall experimental rate constant becomes slower with increasing saccharide concentrations. As we can exclude experimentally that this kinetical effect is caused in presence of the saccharide by a physical quenching of singlet oxygen or of the dye triplet state it has to be assumed that GlcNAc protects the surrounding of its binding place at subsite C of the enzymatic center sterically against an attack of singlet oxygen. In this region three tryptophan residues are located, which could be sensitive against singlet oxygen. Surprisingly, however, it has been found that only those species are protected, in which a second saccharide molecule is bound to the protein, probably at subsite E at the enzymatic center, where no sensitive amino acid side chains are located.

A maltoheptaose-decorated BODIPY photosensitizer for photodynamic inactivation of Gram-positive bacteria

2019 ◽  
Vol 43 (38) ◽  
pp. 15057-15065 ◽  
Author(s):  
Jie Hao ◽  
Zhi Song Lu ◽  
Chang Ming Li ◽  
Li Qun Xu
Keyword(s):  
Singlet Oxygen ◽  
Photodynamic Inactivation ◽  
Gram Positive ◽  
Oxygen Generation ◽  
Gram Positive Bacteria ◽  
Singlet Oxygen Generation

A maltoheptaose-decorated BODIPY with high singlet oxygen generation efficacy was synthesized for photodynamic inactivation of Gram-positive bacteria in planktonic forms and biofilms.

Singlet oxygen production by combining erythrosine and halogen light for photodynamic inactivation of Streptococcus mutans

2016 ◽  
Vol 15 ◽  
pp. 127-132 ◽  
Author(s):  
Camila Fracalossi ◽  
Juliana Yuri Nagata ◽  
Diogo Silva Pellosi ◽  
Raquel Sano Suga Terada ◽  
Noboru Hioka ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Streptococcus Mutans ◽  
Photodynamic Inactivation ◽  
Oxygen Production ◽  
Halogen Light

scholarly journals Development of Singlet Oxygen Luminescence Kinetics during the Photodynamic Inactivation of Green Algae

Molecules ◽  
2016 ◽  
Vol 21 (4) ◽  
pp. 485 ◽  
Author(s):  
Tobias Bornhütter ◽  
Judith Pohl ◽  
Christian Fischer ◽  
Irena Saltsman ◽  
Atif Mahammed ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Green Algae ◽  
Photodynamic Inactivation ◽  
Luminescence Kinetics

scholarly journals Photodynamic Inactivation with Acridine Orange on a Multidrug-resistant Mouse Osteosarcoma Cell Line

2000 ◽  
Vol 91 (4) ◽  
pp. 439-445 ◽  
Author(s):  
Katsuyuki Kusuzaki ◽  
Ginjirou Minami ◽  
Hideyuki Takeshita ◽  
Hiroaki Murata ◽  
Shin Hashiguchi ◽  
...  
Keyword(s):  
Acridine Orange ◽  
Cell Line ◽  
Multidrug Resistant ◽  
Osteosarcoma Cell Line ◽  
Osteosarcoma Cell ◽  
Photodynamic Inactivation ◽  
Resistant Mouse

scholarly journals Potentiation of photoinactivation of Gram-positive and Gram-negative bacteria mediated by six phenothiazinium dyes by addition of azide ion

2014 ◽  
Vol 13 (11) ◽  
pp. 1541-1548 ◽  
Author(s):  
Kamola R. Kasimova ◽  
Magesh Sadasivam ◽  
Giacomo Landi ◽  
Tadeusz Sarna ◽  
Michael R. Hamblin
Keyword(s):  
Singlet Oxygen ◽  
Hydroxyl Radicals ◽  
Gram Negative Bacteria ◽  
Photodynamic Inactivation ◽  
Gram Positive ◽  
Gram Negative ◽  
Azide Ion

Antimicrobial photodynamic inactivation (APDI) using six different phenothiazinium dyes is mediated by singlet oxygen (quenched by azide) and hydroxyl radicals (potentiated by azide) depending on Gram-classification of the bacteria and whether the dye is washed from the cells.

scholarly journals Photodynamic Inactivation of Legionella Pneumophila Biofilm Formation by Cationic Tetra- and Tripyridylporphyrins in Waters of Different Hardness

2021 ◽  
Vol 22 (16) ◽  
pp. 9095
Author(s):  
Martina Mušković ◽  
Iva Ćavar ◽  
Andrija Lesar ◽  
Martin Lončarić ◽  
Nela Malatesti ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Legionella Pneumophila ◽  
Biofilm Formation ◽  
Water Hardness ◽  
Antimicrobial Effect ◽  
Growth Stages ◽  
Photodynamic Inactivation ◽  
Waterborne Diseases ◽  
Biofilm Growth ◽  
Biofilm Destruction

The bacterium Legionella pneumophila is still one of the probable causes of waterborne diseases, causing serious respiratory illnesses. In the aquatic systems, L. pneumophila exists inside free-living amoebae or can form biofilms. Currently developed disinfection methods are not sufficient for complete eradication of L. pneumophila biofilms in water systems of interest. Photodynamic inactivation (PDI) is a method that results in an antimicrobial effect by using a combination of light and a photosensitizer (PS). In this work, the effect of PDI in waters of natural origin and of different hardness, as a treatment against L. pneumophila biofilm, was investigated. Three cationic tripyridylporphyrins, which were previously described as efficient agents against L. pneumophila alone, were used as PSs. We studied how differences in water hardness affect the PSs’ stability, the production of singlet oxygen, and the PDI activity on L. pneumophila adhesion and biofilm formation and in biofilm destruction. Amphiphilic porphyrin showed a stronger tendency for aggregation in hard and soft water, but its production of singlet oxygen was higher in comparison to tri- and tetracationic hydrophilic porphyrins that were stable in all water samples. All three studied porphyrins were shown to be effective as PDI agents against the adhesion of the L. pneumophila to polystyrene, against biofilm formation, and in the destruction of the formed biofilm, in their micromolar concentrations. However, a higher number of dissolved ions, i.e., water hardness, generally reduced somewhat the PDI activity of all the porphyrins at all tested biofilm growth stages.

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