嗜麦芽窄食单胞菌处理苯并a芘-铜复合污染过程中细胞表面特性的变化

摘要

Change of cell surface features of Stenotrophomonas maltophilia in treating BaP and Cu2+ composite pollutants was studied. The results indicated that S. maltophilia was of higher cell surface hydrophobicity (CSH). It could keep within 83.3%-95.6% in treating different pollutant systems for 4-72 h, and then the CSH decreased with increase of operation time. BaP and Cu2+ can make permeability of the cell membrane increase. The morphological features of S. maltophilia observed by TEM showed that cell membrane ruptured and appeared holes on it after treating pollutants, leading to permeability change of cell membrane and outflow of the cytoplasm, but cell wall still kept the cell in original shape without complete splitting. However, after contacting combined pollutants for 5 day, bacterial cells were out of shape seriously, periplasmic space enlarged, and cytoplasm leaked, nucleus broke down and gradually disappeared, resulting in decrease of cell activity and in gradual loss of S. maltophilia's ability adsorbing heavy metals.%利用嗜麦芽窄食单胞菌(Stenotrophomonas maltophilia)对BaPCu进行降解/吸附实验,考察菌体处理污染物过程中细胞表面特性的变化.结果表明,S.maltophilia细胞表面具有较高的疏水性.从4h到72 h,不同污染体系中S.maltophilia的CSH均维持在83.3％～95.6％,之后随着时间的推移,CSH开始逐渐降低.污染物可以使S.maltophilia细胞质膜的通透性增加.TEM检测结果证实处理污染物之后,菌体质膜通透性改变,破裂并出现了“孔洞”,导致细胞质外流,但是细胞壁依然维持细胞形状而没有完全裂解.处理了复合污染物的菌体,到第5d细胞严重变形,周质空间变大,细胞质外泄严重,而且原核分解并逐渐消失,细胞活性降低,并逐渐丧失对重金属的吸附能力.