温度和压力对面包酵母细胞膜通透性的影响

Influence of mild pressure on the permeability of cell membrane of Saccharomyces cerevisiae

以CO2和N2为加压介质,研究了温和压力(1.0 MPa)下加压时间对面包酵母CICC1447、CICC1339细胞膜通透性的影响。结果表明,在压力条件下面包酵母菌悬液的OD260、OD280和电导率增加,说明在温和压力作用下内溶物(核酸、蛋白质)、胞内电解液不断外渗,温和压力可以增强细胞膜的通透性。将酵母细胞在常压下培养至稳定期,制备菌悬液于1 MPa的压力条件下(N2为介质)分别处理1 h、3 h,以常压处理为对照,测定碘化丙啶(PI)与DNA结合产生的荧光强度。结果表明,加压后CICC1447的荧光强度比常压组分别提高了6%、13.56%;CICC1339的荧光强度比常压组分别提高了3%、7%,说明温和压力下酵母细胞膜通透性的变化与细胞膜结构受损相关,压力条件下细胞膜结构完整性受到损伤,导致细胞膜通透性增大。

The effects of mild pressure （1MPa） and holding time on the membrane permeability of Saccharomyces cerevisiae CICC1447, CICC1339 were determined with CO2 and N2 as the pressure media. The results showed that the conductivity of the cell suspension, the 0D26o and 0D28o of the supernatant increased with the pressure increase,which indicated that the cell leakage aggravated with the pressure increase and the membrane permeability increased with the influence of mild pressure. The cells were treated with mild pressure （1MPa） with N2 as the pressure media, and the holding time is lh and 3h respectively. Fluorescence intensity generated by PI and DNA was identified. The results indicated that the fluorescence intensity of CICC1447 improved by 6% and 13.56% compared to normal. And the flu- orescence intensity of CICC1339 improved by 3% and 7%. So the further conclusion was made that mild pressure could increase the permeability of cell membrane of S. cerevisiae.