Maliszewska Irena, Zdubek Anna
Department of Organic and Medicinal Chemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
Int J Mol Sci. 2025 Jul 24;26(15):7153. doi: 10.3390/ijms26157153.
Photodynamic inactivation (aPDI) involves the interaction of three components: non-toxic photosensitizer molecules (PS), low-intensity visible light, and molecular oxygen. This interaction leads to the generation of toxic reactive oxygen species. The present work demonstrated the efficacy of light-induced antimicrobial photodynamic inactivation against and using 5-aminolevulinic acid (5-ALA) as a prodrug to produce the photosensitizer protoporphyrin IX. The photoeradication efficiency of these pathogens under blue (405 nm; 45 mW cm) and red (635 nm; 53 mW cm) light was investigated. Results showed that at least 30 min of blue light irradiation was necessary to achieve a 99.999% reduction of . , whereas red light was less effective. exhibited limited susceptibility under similar conditions. To enhance aPDI efficiency, exogenous glucose was added alongside 5-ALA, which significantly increased the photodynamic efficacy-particularly against -leading to complete eradication after just 5 min of exposure. Spectroscopic analyses confirmed that glucose increased the levels of protoporphyrin IX, which correlated with enhanced photodynamic efficacy. Furthermore, multiple aPDI exposure reduced key virulence factors, including alkaline protease activity, biofilm formation, and swarming motility (in ). These findings suggest that 5-ALA-mediated photodynamic inactivation offers a promising strategy to improve efficacy against resistant Gram-negative pathogens.
光动力灭活（aPDI）涉及三个成分的相互作用：无毒的光敏剂分子（PS）、低强度可见光和分子氧。这种相互作用会导致产生有毒的活性氧物种。本研究使用5-氨基乙酰丙酸（5-ALA）作为前药来产生光敏剂原卟啉IX，证明了光诱导抗菌光动力灭活对[具体细菌名称1]和[具体细菌名称2]的有效性。研究了这些病原体在蓝光（405 nm；45 mW/cm²）和红光（635 nm；53 mW/cm²）照射下的光根除效率。结果表明，至少需要30分钟的蓝光照射才能使[具体细菌名称1]减少99.999%。而红光的效果较差。[具体细菌名称2]在类似条件下表现出有限的敏感性。为了提高aPDI效率，在5-ALA的基础上添加了外源性葡萄糖，这显著提高了光动力效果——特别是对[具体细菌名称1]——在仅暴露5分钟后就导致完全根除。光谱分析证实，葡萄糖增加了原卟啉IX的水平，这与增强的光动力效果相关。此外，多次进行aPDI暴露降低了关键毒力因子，包括碱性蛋白酶活性、生物膜形成和群体运动性（针对[具体细菌名称2]）。这些发现表明，5-ALA介导的光动力灭活为提高对抗耐药革兰氏阴性病原体的疗效提供了一种有前景的策略。
