Hypericin Loaded Liposomes for Anti-Microbial Photodynamic Therapy of Gram-Positive Bacteria

2018 ◽  
Vol 215 (15) ◽  
pp. 1700837 ◽  
Author(s):  
Nikola Plenagl ◽  
Benjamin Sebastian Seitz ◽  
Shashank Reddy Pinnapireddy ◽  
Jarmila Jedelská ◽  
Jana Brüßler ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Gram Positive ◽  
Gram Positive Bacteria

scholarly journals Type I and Type II mechanisms of antimicrobial photodynamic therapy: An in vitro study on gram-negative and gram-positive bacteria

2012 ◽  
Vol 44 (6) ◽  
pp. 490-499 ◽  
Author(s):  
Liyi Huang ◽  
Yi Xuan ◽  
Yuichiro Koide ◽  
Timur Zhiyentayev ◽  
Masamitsu Tanaka ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
In Vitro Study ◽  
Vitro Study ◽  
Type I ◽  
Antimicrobial Photodynamic Therapy ◽  
Type Ii ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

scholarly journals Water-dispersible glycosylated poly(2,5′-thienylene)porphyrin-based nanoparticles for antibacterial photodynamic therapy

2019 ◽  
Vol 18 (5) ◽  
pp. 1147-1155 ◽  
Author(s):  
Rehan Khan ◽  
Melis Özkan ◽  
Aisan Khaligh ◽  
Dönüs Tuncel
Keyword(s):  
Antibacterial Activity ◽  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Water Dispersible ◽  
Gram Positive Bacteria ◽  
High Yields

Water-dispersible glycosylated poly(2,5′-thienylene)porphyrin-based nanoparticles have the ability to generate singlet oxygen in high yields and exhibit light-triggered antibacterial activity against Gram negative bacteria, E. coli as well as Gram positive bacteria, B. subtilis.

scholarly journals A Novel Water-Soluble Photosensitizer for Photodynamic Inactivation of Gram-Positive Bacteria

2020 ◽  
Author(s):  
Zihuayuan Yang ◽  
Ying Qiao ◽  
Junying Li ◽  
Fu-Gen Wu ◽  
Fengming Lin
Keyword(s):  
Photodynamic Therapy ◽  
Water Solubility ◽  
Uv Light ◽  
Water Soluble ◽  
Light Irradiation ◽  
Microbial Fermentation ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Uv Light Irradiation

AbstractAntimicrobial photodynamic therapy (APDT) is a promising alternative to traditional antibiotics for bacterial infections, which inactivates a broad spectrum of bacteria. However, it has some disadvantages including poor water solubility and easy aggregation of hydrophobic photosensitizers (PS), and poor tissue penetration and cytotoxicity when using UV as the light source, leading to undesired photodynamic therapy efficacy. Herein, we develop a novel water-soluble natural PS (sorbicillinoids) obtained by microbial fermentation using recombinant filamentous fungus Trichoderma reesei (T. reesei). Sorbicillinoids could effectively generate singlet oxygen (1O2) under ultraviolet (UV) light irradiation, and ultimately display photoinactivation activity on Gram-positive bacteria, but not Gram-negative ones. Staphylococcus aureus (S. aureus) treated with sorbicillinoids and UV light displayed high levels of intracellular reactive oxygen species (ROS), notable DNA photocleavage, and compromised cell semi-permeability without overt cell membrane disruption. Moreover, the dark toxicity, phototoxicity or hemolysis activity of sorbicillinoids is negligible, showing its excellent biocompatibility. Therefore, sorbicillinoids, a type of secondary metabolite from fungus, has a promising future as a new PS for APDT using nontoxic dose of UV light irradiation.ImportanceIt is of great value to develop novel PSs for APDT to enhance its efficacy for the reason that many traditional PSs have disadvantages like low water solubility and poor biocompatibility. In this study, we develop a novel water-soluble natural PS - sorbicillinoids obtained by microbial fermentation using T. reesei. Sorbicillinoids could effectively generate singlet oxygen under UV light irradiation, and ultimately display photoinactivation activity on Gram-positive bacteria, but not Gram-negative ones. More importantly, UV light can generally only be used to inactivate bacteria on the surface due to its weak penetration. However, it can penetrate deep into the solution and inactivate bacteria in the presence of sorbicillinoids. Therefore, sorbicillinoids, a type of secondary metabolite from fungus, has a promising future as a new PS for APDT using nontoxic dose of UV light irradiation.

Multifunctional BODIPY for effective inactivation of Gram-positive bacteria and promotion of wound healing

2021 ◽  
Author(s):  
Chaonan Li ◽  
Yite Li ◽  
Qihang Wu ◽  
Tingting Sun ◽  
Zhigang Xie
Keyword(s):  
Wound Healing ◽  
Photodynamic Therapy ◽  
Antimicrobial Resistance ◽  
Infectious Diseases ◽  
Human Health ◽  
Bacterial Infections ◽  
Alternative Therapies ◽  
Gram Positive ◽  
Gram Positive Bacteria

Bacterial infectious diseases and antimicrobial resistance seriously endanger human health, so alternative therapies for bacterial infections are urgently needed. Recently, photodynamic therapy against bacteria has shown great potential because of...

Efficient photosensitizers with aggregation-induced emission characteristics for lysosome- and Gram-positive bacteria-targeted photodynamic therapy

2020 ◽  
Vol 56 (17) ◽  
pp. 2630-2633 ◽  
Author(s):  
Jiabao Zhuang ◽  
Hanxiao Yang ◽  
Yue Li ◽  
Bing Wang ◽  
Nan Li ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Cancer Cells ◽  
White Light ◽  
Light Irradiation ◽  
Emission Characteristics ◽  
Gram Positive ◽  
Aggregation Induced Emission ◽  
Gram Positive Bacteria ◽  
Targeted Photodynamic Therapy

Efficient photosensitizers with aggregation-induced emission effects were reported to selectively stain lysosome and Gram-positive bacteria, which further triggered the ablation of cancer cells and bacteria under white light irradiation.

scholarly journals Novel Water-Soluble Photosensitizer for Photodynamic Inactivation of Gram-Positive Bacteria Using Nontoxic Dose of UV Light

2020 ◽  
Author(s):  
Zihuayuan Yang ◽  
Ying Qiao ◽  
Junying Li ◽  
Fu-Gen Wu ◽  
Fengming Lin
Keyword(s):  
Photodynamic Therapy ◽  
Bacterial Infections ◽  
Water Solubility ◽  
Uv Light ◽  
Water Soluble ◽  
Light Irradiation ◽  
Gram Positive ◽  
Promising Alternative ◽  
Gram Positive Bacteria ◽  
Uv Light Irradiation

Abstract Background Antimicrobial photodynamic therapy (APDT) is a promising alternative to traditional antibiotics for bacterial infections, which inactivates a broad spectrum of bacteria. However, it has some disadvantages including poor water solubility and easy aggregation of hydrophobic photosensitizers (PS), and poor tissue penetration and cytotoxicity when using UV as the light source, leading to undesired photodynamic therapy efficacy.Results In this study, we develop a novel water-soluble natural PS (sorbicillinoids) obtained by microbial fermentation using recombinant filamentous fungus Trichoderma reesei (T. reesei). Sorbicillinoids could effectively generate singlet oxygen (1O2) under ultraviolet (UV) light irradiation, and ultimately display photoinactivation activity on Gram-positive bacteria, but not Gram-negative ones. Staphylococcus aureus (S. aureus) treated with sorbicillinoids and UV light displayed high levels of intracellular reactive oxygen species (ROS), notable DNA photocleavage, and compromised cell semi-permeability without overt cell membrane disruption. Moreover, the dark toxicity, phototoxicity or hemolysis activity of sorbicillinoids is negligible, showing its excellent biocompatibility.Conclusion Sorbicillinoids obtained from T. reesei display photoinactivation activity on Gram-positive bacteria using nontoxic dose of UV light irradiation and have an excellent biocompatibility Therefore, sorbicillinoids, a type of secondary metabolite from fungus, has a promising future as a new PS for APDT.

Influence of Cell Wall Composition on the Fossilisation of Bacteria and the Implications for the Search for Early Life Forms

1997 ◽  
Vol 161 ◽  
pp. 491-504 ◽  
Author(s):  
Frances Westall
Keyword(s):  
Cell Wall ◽  
Life Forms ◽  
Cation Binding ◽  
Positive Bacterium ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Transmission Electron ◽  
Hydrothermal Sediments ◽  
Identification Of Bacteria ◽  
The Difference

AbstractThe oldest cell-like structures on Earth are preserved in silicified lagoonal, shallow sea or hydrothermal sediments, such as some Archean formations in Western Australia and South Africa. Previous studies concentrated on the search for organic fossils in Archean rocks. Observations of silicified bacteria (as silica minerals) are scarce for both the Precambrian and the Phanerozoic, but reports of mineral bacteria finds, in general, are increasing. The problems associated with the identification of authentic fossil bacteria and, if possible, closer identification of bacteria type can, in part, be overcome by experimental fossilisation studies. These have shown that not all bacteria fossilise in the same way and, indeed, some seem to be very resistent to fossilisation. This paper deals with a transmission electron microscope investigation of the silicification of four species of bacteria commonly found in the environment. The Gram positiveBacillus laterosporusand its spore produced a robust, durable crust upon silicification, whereas the Gram negativePseudomonas fluorescens, Ps. vesicularis, andPs. acidovoranspresented delicately preserved walls. The greater amount of peptidoglycan, containing abundant metal cation binding sites, in the cell wall of the Gram positive bacterium, probably accounts for the difference in the mode of fossilisation. The Gram positive bacteria are, therefore, probably most likely to be preserved in the terrestrial and extraterrestrial rock record.

Microanatomy of the Periplasm of Bacillus Licheniformis

1971 ◽  
Vol 29 ◽  
pp. 262-263
Author(s):  
B.K. Ghosh
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Bacillus Licheniformis ◽  
External Environment ◽  
Permeability Barrier ◽  
Periplasmic Space ◽  
Modified Technique ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.

Rapid demonstration of septic or infectious arthritis due to Gram-negative bacteria

1992 ◽  
Vol 50 (1) ◽  
pp. 686-687
Author(s):  
Jacob S. Hanker ◽  
Paul R. Gross ◽  
Beverly L. Giammara
Keyword(s):  
Chronic Arthritis ◽  
Blood Cultures ◽  
Gram Negative Bacteria ◽  
Infectious Arthritis ◽  
Bacterial Arthritis ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Blood cultures are positive in approximately only 50 per cent of the patients with nongonococcal bacterial infectious arthritis and about 20 per cent of those with gonococcal arthritis. But the concept that gram-negative bacteria could be involved even in chronic arthritis is well-supported. Gram stains are more definitive in staphylococcal arthritis caused by gram-positive bacteria than in bacterial arthritis due to gram-negative bacteria. In the latter situation where gram-negative bacilli are the problem, Gram stains are helpful for 50% of the patients; they are only helpful for 25% of the patients, however, where gram-negative gonococci are the problem. In arthritis due to gram-positive Staphylococci. Gramstained smears are positive for 75% of the patients.

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