Department of Chemical Engineering, The University of Michigan, Ann Arbor, MI 48109, USA.
Biotechnol Bioeng. 1992 Mar 25;39(7):732-40. doi: 10.1002/bit.260390706.
Overall protein release greater than 75% in less than 1 h can be attained by exposing exponentially growing Escherichia coli cells to 0.4 M guanidine plus 0.5% Triton X-100 at 37 degrees C in medium. Cell growth stops immediately upon addition of the chemicals, but the cells are not lysed. Guanidine concentrations lower than 0.2 M, in conjunction with 0.5% Triton X-100, do not release significant intracellular protein, nor do they inhibit cell growth. Under these conditions, the cells undergo an adaptation that confers resistance to protein release by further treatment with guanidine and Triton X-100. Cells treated with 0.2 M guanidine plus 0.5% Triton X-100 display intermediate behavior. Protein release is approximately 35%, and growth is temporarily interrupted by an extended lag phase. Subsequent resumption of cell growth results in resistant cells and no additional protein release. This resistance is shown to be reversible and is most likely due to physiological adaptation rather than genetic mutation.
在培养基中，使指数生长期的大肠杆菌细胞暴露于 0.4 M 盐酸胍和 0.5% Triton X-100 中，于 37°C 下可在 1 小时内获得超过 75%的总蛋白释放。化学物质加入后，细胞生长立即停止，但细胞并未裂解。盐酸胍浓度低于 0.2 M，与 0.5% Triton X-100 联合使用，不会释放大量细胞内蛋白，也不会抑制细胞生长。在这些条件下，细胞会发生适应性变化，从而对进一步用盐酸胍和 Triton X-100 处理产生抗蛋白释放的能力。用 0.2 M 盐酸胍和 0.5% Triton X-100 处理的细胞表现出中间行为。蛋白释放约为 35%，并且生长通过延长的迟滞期暂时中断。随后细胞生长的恢复导致产生抗性细胞，并且没有额外的蛋白释放。这种抗性被证明是可逆的，很可能是由于生理适应而不是基因突变所致。
