BACKGROUND Pseudomonas aeruginosa forms antibiotic-resistant biofilms that are responsible for the treatment failure or relapses of the bacterial infections in the lungs of patients with cystic fibrosis (CF). The alginate lyases that target extracellular polysaccharide alginate of P. aeruginosa biofilms are promising therapeutic candidates for treatment of P. aeruginosa biofilm infections. METHODS Immunofluorescent staining and thin layer chromatography were used to demonstrate the alginolytic activity of the alginate lyase enzyme (AlyP1400) purified from a marine Pseudoalteromonas bacterium. Anti-biofilm activities of AlyP1400 were tested alone or in combination with antibiotics on the biofilms of a mucoid Pseudomonas aeruginosa clinical isolate CF27 that were cultivated in 96-well plates and a flow cell. RESULTS We showed that AlyP1400 facilitated antibiotic activities to eliminate CF27 biofilms. The combination of AlyP1400 with antibiotics reduced the biofilm biomass and boosted bactericidal activity of antibiotics. Importantly, we demonstrated that the enzymatic activity of AlyP1400 was required for its biofilm disruption activity and its synergy with antibiotics to eradicate biofilm cells. CONCLUSION This work shed new light on the potential mechanisms of the therapeutic activity for the combinational use of alginate lyase and antibiotics to treat P. aeruginosa infections in CF lungs or other P. aeruginosa biofilm-related infections.

中文翻译：

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藻酸盐裂解酶破坏铜绿假单胞菌生物膜的细胞外聚合网络可增强抗生素对病原体的根除

背景技术铜绿假单胞菌形成耐抗生素的生物膜，导致囊性纤维化（CF）患者肺部细菌感染的治疗失败或复发。靶向铜绿假单胞菌生物膜细胞外多糖藻酸盐的藻酸盐裂合酶是治疗铜绿假单胞菌生物膜感染的有希望的治疗候选物。方法 免疫荧光染色和薄层色谱用于证明从海洋假交替单胞菌中纯化的藻酸裂解酶 (AlyP1400) 的溶藻活性。AlyP1400 的抗生物膜活性单独或与抗生素联合对在 96 孔板和流通池中培养的粘液性铜绿假单胞菌临床分离株 CF27 的生物膜进行了测试。结果 我们发现 AlyP1400 促进了抗生素活性以消除 CF27 生物膜。AlyP1400 与抗生素的组合减少了生物膜生物量并提高了抗生素的杀菌活性。重要的是，我们证明了 AlyP1400 的酶活性是其生物膜破坏活性及其与抗生素协同消灭生物膜细胞所必需的。结论 这项工作为联合使用藻酸盐裂解酶和抗生素治疗 CF 肺中的铜绿假单胞菌感染或其他铜绿假单胞菌生物膜相关感染的治疗活性的潜在机制提供了新的线索。我们证明了 AlyP1400 的酶活性是其生物膜破坏活性及其与抗生素协同消灭生物膜细胞所必需的。结论 这项工作为联合使用藻酸盐裂解酶和抗生素治疗 CF 肺中的铜绿假单胞菌感染或其他铜绿假单胞菌生物膜相关感染的治疗活性的潜在机制提供了新的线索。我们证明了 AlyP1400 的酶活性是其生物膜破坏活性及其与抗生素协同消灭生物膜细胞所必需的。结论 这项工作为联合使用藻酸盐裂解酶和抗生素治疗 CF 肺中的铜绿假单胞菌感染或其他铜绿假单胞菌生物膜相关感染的治疗活性的潜在机制提供了新的线索。