Microbial evolution in a simple unstructured environment: genetic differentiation in Escherichia coli.
Microbial evolution in a simple unstructured environment: genetic differentiation in Escherichia coli.
复制标题
简单非结构化环境中的微生物进化：大肠杆菌的遗传分化。
DOI：
10.1093/genetics/137.4.903
复制
发表时间：
1994
期刊：
影响因子：
3.3
通讯作者：
Adams,J
中科院分区：
文献类型：
--
作者：
Rosenzweig,RF;Sharp,RR;Treves,DS;Adams,J
大肠杆菌群体开始于单一克隆，并在葡萄糖限制的连续培养中保持很长时间，变得多态。在一个人口中，三个克隆被分离出来，并通过重建实验被证明是保持在稳定的多态性，虽然他们表现出显着的差异，在最大比生长速率和葡萄糖摄取动力学。这三个克隆的分析表明，它们的稳定共存可以解释两个替代代谢物乙酸和甘油的分泌和摄取的差异模式。乙酰辅酶A合成酶中的调节（组成型和无效）突变解释了所观察到的乙酸盐分泌和摄取的不同模式。甘油摄取模式的改变最有可能由突变解释，突变导致甘油调节子诱导的定量差异和/或甘油激酶的结构变化，从而减少与糖酵解相关的效应分子的变构抑制。资源分配的演变和由此产生的多态现象可以说明无性生物的物种形成的初期过程。
Populations of Escherichia coli initiated with a single clone and maintained for long periods in glucose-limited continuous culture, become polymorphic. In one population, three clones were isolated and by means of reconstruction experiments were shown to be maintained in stable polymorphism, although they exhibited substantial differences in maximum specific growth rates and in glucose uptake kinetics. Analysis of these three clones revealed that their stable coexistence could be explained by differential patterns of the secretion and uptake of two alternative metabolites acetate and glycerol. Regulatory (constitutive and null) mutations in acetyl-coenzyme A synthetase accounted for different patterns of acetate secretion and uptake seen. Altered patterns in glycerol uptake are most likely explained by mutations which result in quantitative differences in the induction of the glycerol regulon and/or structural changes in glycerol kinase that reduce allosteric inhibition by effector molecules associated with glycolysis. The evolution of resource partitioning, and consequent polymorphisms which arise may illustrate incipient processes of speciation in asexual organisms.