产甘油假丝酵母稳定期酸胁迫耐受性研究

摘要

研究了产甘油假丝酵母稳定期的酸胁迫耐受性.结果表明,在一定的酸性pH值范围内,pH值降低而酸胁迫压力增加,可以促进产甘油假丝酵母胞内聚磷酸盐积累,从而保证细胞免受酸胁迫的过度影响,维持较高甘油生产水平所需的活细胞数;但过高的酸性环境会严重损伤细胞,降低细胞合成聚磷酸盐的能力,从而使细胞存活率和甘油产量下降.产甘油假丝酵母胞内积累聚磷酸盐,可以增强其对营养饥饿和强酸胁迫等的抵抗力,从而提高其在生长稳定期的存活率.%Acidic stress tolerance of Candida glycerinogenes was studied by controlling pH value in the stationary stage. The results demonstrated that, in certain range of acidic pH value, intracellular polyphosphate (PolyP) accu-mulation by C. glycerinogenes can be promoted by the increase of acidic stress. PolyP accumulation can keep cells from greatly influenced by acidic stress and maintain enough live cells to achieve the higher level of glycerol produc-tion. However, too high acidic stress can greatly destroy yeast cells, thus largely decreasing PolyP accumulation, cells survival and glycerol production. The conclusion that intracellular Polyp accumulation by C. glycerinogenes can strengthen cells resistance for nutrition-deficiency and high acidic stress and increase cells survival in the stationary stage could be made.