Growth responses of ciliate protozoa to the abundance of their bacterial prey
Growth responses of ciliate protozoa to the abundance of their bacterial prey
复制标题
纤毛虫原生动物对其细菌猎物丰度的生长反应
作者：
W. Taylor
在单细胞培养中检查了五种菌食性纤毛虫对产气肠杆菌丰度的生长速率或数值响应。从一个小池塘中分离出纤毛虫Colpidium Campylum、C. colpoda、Glucoma scintillons、G. frontata 和Cyclidium glaucoma。其中四种在摇动的培养物中生长，而三种在允许细菌沉淀在培养容器底部的培养物中生长。在生成的七个响应曲线中，四个具有不同的阈值，因此通常适合纤毛虫数值响应曲线的米氏模型并不合适。在摇动培养物中，半饱和猎物密度范围为 5.5 × 106 至 42.9 × 106 个细菌/ml。在未摇动的培养物中，半饱和密度范围为 0.057 × 106 至 14.6 × 106 个细菌/cm2。在悬浮细菌和定居细菌上生长的两个物种获得了更高的生长速率，并且以定居细菌为食的半饱和猎物密度更低。
The growth rate or numerical response of five species of bactivorous ciliates to the abundance ofEnterobacter aerogenes was examined in monoxenic culture. The ciliatesColpidium campylum, C. colpoda, Glaucoma scintillons, G. frontata, andCyclidium glaucoma were isolated from a small pond. Four were grown in shaken cultures, while three were grown in cultures in which the bacteria were allowed to settle on the bottom of the culture vessel. Of the seven response curves generated, four had distinct thresholds, so that the Michaelis-Menten model usually fitted to ciliate numerical response curves was not appropriate. In shaken cultures, half-saturation prey densities ranged from 5.5 × 106 to 42.9 × 106 bacteria/ml. In unshaken cultures, half-saturation densities ranged from 0.057 × 106 to 14.6 × 106 bacteria/cm2. Two species grown on both suspended and settled bacteria attained higher growth rates and had lower half-saturation prey densities feeding on settled bacteria.