舍瓦内拉
胞外聚合物
溶解
萃取(化学)
乙二胺四乙酸
多糖
化学
离心
色谱法
细胞外
生物化学
细菌
生物
螯合作用
生物膜
有机化学
遗传学
作者
You-Fen Dai,Yong Xiao,Enhua Zhang,Lidan Liu,Ling Qiu,Le-Xing You,Gurumurthy Dummi Mahadevan,Bilian Chen,Feng Zhao
摘要
Extracellular polymeric substances (EPS) play crucial roles in bio-aggregate formation and survival of bacterial cells. To develop an effective but harmless method for EPS extraction from Shewanella oneidensis MR-1, five extraction methods, i.e. centrifugation (control), heating (40, 45, 50, and 60 °C), and treatments with H2SO4, ethylenediaminetetraacetic acid (EDTA) and NaOH, were examined, respectively. Results from scanning electron microscope and flow cytometric analyses indicate that MR-1 cells were severely broken by H2SO4, NaOH and heating temperature ≥45 °C. Proteins and polysaccharides in EPS extracted by heating at 40 °C were 7.12 and 1.60 mg g−1 dry cell, respectively. Although EDTA treatment had a relatively lower yield of EPS (proteins and polysaccharides yields of 5.15 and 1.30 mg g−1 dry cell, respectively), cell lysis was barely found after EPS extraction. Three peaks were identified from the three-dimensional excitation–emission matrix spectrum of each EPS sample, suggesting the presence of protein-like substances. Furthermore, the peak intensity was in good accordance with protein concentration measured by the chemical analysis. In short, heating (40 °C) and EDTA treatments were found the most suitable methods for EPS extraction considering the cell lysis and EPS content, composition and functional groups together.
科研通智能强力驱动
Strongly Powered by AbleSci AI