The Polymorphic Life History of Tetrahymena patula
The Polymorphic Life History of Tetrahymena patula
复制标题
孔雀四膜虫的多态性生活史
DOI：
10.1111/j.1550-7408.1960.tb00701.x
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发表时间：
1960
影响因子：
2.2
通讯作者：
N. E. Williams
中科院分区：
文献类型：
--
作者：
N. E. Williams
SYNOPSIS.
Dimorphic populations of Tetrahymena patula L-FF result when this organism is grown axenically in Loefer's medium supplemented with aqueous lettuce extract. The two different cell types in these cultures are identified as “macrostomes”and “microstomes.” Isolation of microstomes and macrostomes from the dimorphic cultures has shown that both cell types reproduce by binary fission in this medium, and further that each cell type will occasionally give rise to the other under these conditions. Isolation experiments have also shown that both microstomes and macrostomes from the dimorphic cultures are capable of giving rise to the reproductive cyst. The cells which are liberated from the cyst have small mouths but are best referred to as “tomites,” in order to distinguish them from the self-perpetuating microstomes described above. The relatively small, rapidly swimming tomites will either transform into macrostomes or reproduce as microstomes. The life histoy of T. patula thus consists of three cell types as follows, each capable of giving rise to the other two: a macrostome, a microstome, and a tomite. Silver preparations of the dimorphic cultures have shown that oral replacement takes place. This consists of resorption of the oral apparatus and its replacement by differentiation of new mouth parts from an anarchic field of kinetosomes which arises immediately posterior to the old oral apparatus. It is suggested that this process is involved in the macrostome-microstome interconversions.
Growth curves were determined for T. patula feeding on a variety of substrates. These data indicate that this species is extremely well adapted as a carnivore. It grows very poorly on bacteria, but will grow well in axenic culture if aqueous lettuce extract is provided. The lettuce extract greatly reduces the generation time and increases the maximum cell density.
Loss of the micronucleus in stain L-FF is reported and discussed. The loss may be an indication that this strain has entered the senile phase of the Maupasian life cycle.
