Failla M L, Weinberg E D
J Gen Microbiol. 1977 Mar;99(1):85-97. doi: 10.1099/00221287-99-1-85.
Intracellular accumulation of zinc by Candida utilis NRRL-Y-7634 was mediated by an energy-and temperature-dependent, highly specific process exhibiting saturation kinetics. In zinc-supplemented medium, uptake occured only during the lad and late-exponential phases; this type of transport did not occur with zinc in bacteria nor with iron in either yeast or bacteria. Cells of C. utilis did not possess a zinc-efflux system; they could reduce their level of intracellular zinc only by dilution of the metal into daughter cells. Zinc-deficient organisms accumulated 12 times more zinc than did cells of the same culture age grown in zinc-supplemented medium. The varied, but experimentally reproducible levels of intracellular zinc that occured in response to the physiological and environmental parameters had no detectable effects on respiration, rate of growth, total cell yield, or cell viability. Neither the mechanism underlying the cyclic accumulation of sinc nor the function of such behaviour are understood.
产朊假丝酵母NRRL-Y-7634细胞内锌的积累是由一个能量和温度依赖性的、高度特异性的过程介导的，该过程表现出饱和动力学。在添加锌的培养基中，摄取仅发生在延滞期和指数生长后期；这种转运类型在细菌中对锌以及在酵母或细菌中对铁均未出现。产朊假丝酵母细胞不具备锌外流系统；它们只能通过将金属稀释到子细胞中来降低细胞内锌的水平。缺锌的生物体积累的锌比在添加锌的培养基中生长的相同培养年龄的细胞多12倍。响应生理和环境参数而出现的细胞内锌水平变化但可实验重现，对呼吸、生长速率、总细胞产量或细胞活力均无可检测到的影响。锌循环积累的潜在机制及其这种行为的功能均尚不清楚。
