鲶鱼体表粘液粗提物对铜绿假单胞菌的抑菌机理初探

Antibacterial Mechanisms of Catfish Epidermal Mucus Extracts against Pseudomonas aeruginosa

本文以铜绿假单胞菌为研究对象,探讨鲶鱼体表粘液提取物(Catfish Epidermal Mucus Extracts,CEME)对其的抑制效果及抑菌机理。研究表明:当CEME浓度高于0.15%时,鲶鱼体表粘液提取物对铜绿假单胞菌有显著的抑制作用,通过测定微生物的生长曲线可以看出CEME能够有效减缓铜绿假单胞菌的生长速率。进一步使用扫描电镜发现CEME对铜绿假单胞菌的细胞形态结构能够造成明显的损伤,有效破坏微生物细胞膜的完整性。同时CEME还可以导致铜绿假单胞菌细胞膜的通透性增加,从而导致体内小分子物质以及部分大分子物质向外泄漏。应用SDS-PAGE方法发现CEME处理对铜绿假单胞菌的总蛋白和细菌膜蛋白均有显著的影响,它能够抑制菌体某些蛋白的合成,导致胞内蛋白含量的下降和缺失。上述研究结果表明鲶鱼体表粘液提取物对铜绿假单胞菌有较好的抑制效果。

Several techniques were used to investigate the mechanism of antibacterial effect of catfish epidermal mucus extracts(CEME) against Pseudomonas aeruginosa. The results showed that the inhibitory effect was significant when the concentration exceeded 0.15%(mg/m L). The bacterial growth curve showed a decrease and scanning electron microscopy(SEM) showed changes in morphology. This indicated that the primary mechanism of CEME inhibitory action was to damage the bacterial cell membrane integrity. CEME also increased bacterial membrane permeability, which led to leakage of cellular small molecules and a proportion of macromolecules. In addition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) revealed that CEME causes obvious changes to bacterial membrane proteins, which led to inhibition of bacterial protein synthesis and subsequent decline and loss of intracellular protein content. These results imply that CEME shows relatively good antibacterial effect on Pseudomonas aeruginosa.