Programa de Pós-Graduação em Medicina Veterinária, Universidade Federal de Santa Maria (UFSM), Av. Roraima, 1000, Santa Maria, RS, 97105-900, Brazil.
Laboratório de Bioinorgânica e Materiais Porfirínicos, Departamento de Química, UFSM, Av. Roraima, 1000, Santa Maria, RS, 97105-900, Brazil.
Microb Pathog. 2023 May;178:106081. doi: 10.1016/j.micpath.2023.106081. Epub 2023 Mar 21.
Infectious bovine keratoconjunctivitis (IBK) is the most important eye disease in ruminants worldwide. Moraxella bovis and Moraxella bovoculi can form biofilm and are frequently isolated from affected animals. Antimicrobials are used worldwide to treat clinical cases of IBK, although they have limited success in clearing the infection. Therefore, photodynamic therapy using porphyrins as photosensitizing molecules is an alternative method to eliminate microorganisms, including biofilms. We evaluated the antibacterial activity of a zinc(II) metalloporphyrin (ZnTMeP) against M. bovis and M. bovoculi biofilms since this compound can efficiently inactivate planktonic Moraxella spp. This study was carried out with two reference strains of Moraxella spp. (M. bovis: ATCC® 10900 and M. bovoculli: ATCC® BAA1259). The antibacterial activity of 4.0 μM of the ZnTMeP porphyrin was evaluated on forming and consolidate biofilms with three 30-min cycles of white-light exposure for three days. The ZnTMeP porphyrin reduced M. bovis and M. bovoculi biofilm formation. In addition, ZnTMeP partially destroyed consolidated M. bovoculi biofilms in the second white-light irradiation cycle, although the porphyrin had no effect against the consolidated biofilm of M. bovis. Despite the biofilm still not being completely inactivated, our findings are promising and encourage further experiments using the phototherapy protocol.
传染性牛角膜结膜炎（IBK）是世界范围内反刍动物最重要的眼部疾病。莫拉氏菌和牛眼莫拉氏菌可以形成生物膜，并且经常从受感染的动物中分离出来。全世界都在使用抗生素治疗 IBK 的临床病例，尽管它们在清除感染方面的效果有限。因此，使用卟啉作为光敏分子的光动力疗法是消除微生物（包括生物膜）的替代方法。我们评估了一种锌（II）金属卟啉（ZnTMeP）对牛莫拉氏菌和牛眼莫拉氏菌生物膜的抗菌活性，因为该化合物可以有效地使浮游莫拉氏菌失活。这项研究使用了两种莫拉氏菌参考菌株（牛莫拉氏菌：ATCC® 10900 和牛眼莫拉氏菌：ATCC® BAA1259）进行。用三个 30 分钟的白光照射周期，每天三次，评估了 4.0 μM ZnTMeP 卟啉对形成和巩固生物膜的抗菌活性。ZnTMeP 卟啉减少了牛莫拉氏菌和牛眼莫拉氏菌生物膜的形成。此外，ZnTMeP 在第二个白光照射循环中部分破坏了巩固的牛眼莫拉氏菌生物膜，尽管卟啉对牛莫拉氏菌的巩固生物膜没有影响。尽管生物膜仍未完全失活，但我们的发现很有希望，并鼓励进一步使用光疗方案进行实验。
