目的:本研究旨在通过生理分析研究柠檬酸作用下天蚕细胞膜结构和功能的变化。
结果:膜的完整性,表面疏水性,结构,流动性,碘化丙啶染色测定I.terricolaWJL-G4细胞的凋亡和脂肪酸甲酯组成,微生物对碳氢化合物的粘附试验,透射电子显微镜分析,荧光各向异性,流式细胞术和气相色谱-质谱,分别。结果表明,随着柠檬酸浓度的增加,细胞活力,I.terricola的膜完整性和流动性降低;同时,凋亡率,膜可渗透,疏水性和麦角甾醇含量显着增加。与控制相比,Na+的活动,K+-ATP酶和Ca2+,Mg2+-ATP酶增加了3.73倍和6.70倍,分别,当柠檬酸浓度增加到20gL-1时。当柠檬酸浓度达到80gL-1时,细胞破裂,细胞质流出。
结论:I.在60gL-1以下柠檬酸浓度下,terricola可以成功调节其膜结构和功能。然而,当柠檬酸浓度高于80gL-1时,其结构和功能发生了巨大变化,这可能会导致功能降低。
OBJECTIVE: This study aimed to investigate the changes of cell membrane structure and function of Issatchenkia terricola under citric acid by performing physiological analysis.
RESULTS: The membrane integrity, surface hydrophobicity, structure, fluidity, apoptosis, and fatty acid methyl esters composition of I. terricola WJL-G4 cells were determined by propidium iodide staining, microbial adhesion to hydrocarbon test, transmission electron microscopy analysis, fluorescence anisotropy, flow cytometry, and gas chromatography-mass, respectively. The results showed that with the increasing of citric acid concentrations, the cell vitality, membrane integrity, and fluidity of I. terricola reduced; meanwhile, apoptosis rate, membrane permeable, hydrophobicity, and ergosterol contents augmented significantly. Compared to control, the activities of Na+, K+-ATPase, and Ca2+, Mg2+-ATPase increased by 3.73-fold and 6.70-fold, respectively, when citric acid concentration increased to 20 g l-1. The cells cracked and their cytoplasm effused when the citric acid concentration reached 80 g l-1.
CONCLUSIONS: I. terricola could successfully adjust its membrane structure and function below 60 g l-1 of citric acid. However, for citric acid concentrations above 80 g l-1, its structure and function were dramatically changed, which might result in reduced functionality.