Abstract：
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.
摘要：
感染性牛角膜结膜炎(IBK)是全世界反刍动物中最重要的眼病。牛莫拉氏菌和博克莫拉氏菌可以形成生物膜，并且经常从受影响的动物中分离出来。抗菌药物在全球范围内用于治疗IBK的临床病例，尽管他们在清除感染方面的成功有限。因此,使用卟啉作为光敏分子的光动力疗法是消除微生物的替代方法，包括生物膜。我们评估了锌（II）金属卟啉（ZnTMeP）对牛M.bovis和M.bovoculi生物膜的抗菌活性，因为该化合物可以有效地灭活浮游莫拉氏菌。这项研究是用两个莫拉氏菌属的参考菌株进行的。(M.牛：ATCC®10900和M.bovoculli：ATCC®BAA1259）。4.0μM的ZnTMeP卟啉的抗菌活性是根据其形成和巩固生物膜的能力进行评估的，其中三个30分钟的白光暴露周期为三天。ZnTMeP卟啉减少了牛分枝杆菌和博沃氏菌生物膜的形成。此外,ZnTMeP在第二个白光照射周期中部分破坏了固结的博沃武利生物膜，虽然卟啉对牛分枝杆菌的固结生物膜没有影响。尽管生物膜仍未完全失活,我们的发现是有希望的，并鼓励使用光疗方案进行进一步的实验。
