Autoradiographic studies of chromosome replication during the cell cycle of Streptococcus faecium.
Autoradiographic studies of chromosome replication during the cell cycle of Streptococcus faecium.
复制标题
屎链球菌细胞周期中染色体复制的放射自显影研究。
DOI：
10.1128/jb.168.2.541-547.1986
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发表时间：
1986
影响因子：
3.2
通讯作者：
Daneo-Moore,L
中科院分区：
文献类型：
--
作者：
Higgins,ML;Koch,AL;Dicker,DT;Daneo-Moore,L
对连续或脉冲标记氚胸苷(质量倍增时间，90min)的粪链球菌细胞周围放射自显影颗粒分布的分析表明，即使考虑到研究人群中细胞大小的分布，也是非泊松分布的。这些颗粒的非泊松分布被认为反映了染色体复制的不连续性质。为了进一步研究这种不连续的过程，我们对观察到的脉冲标记细胞的颗粒分布拟合了一个方程，该方程假设在任何细胞群体中都有亚群，其中有零个、一个或两个复制的染色体。这一分析预测了染色体复制的平均时间和完成染色体复制和分裂之间的平均时间分别为55分钟和43分钟，这与其他技术的估计非常一致。本研究扩展了过去的研究，表明染色体复制的开始和完成随着细胞体积的增加而变化不明显，并且染色体复制量在不同的细胞部分可能是不同的。
Analysis of the distribution of autoradiographic grains around cells of Streptococcus faecium which had been either continuously or pulse-labeled with tritiated thymidine (mass doubling time, 90 min) showed a non-Poisson distribution even when the distribution of cell sizes in the populations studied was taken into account. These non-Poisson distributions of grains were assumed to reflect the discontinuous nature of chromosome replication. To study this discontinuous process further, we fitted an equation to the grain distribution observed for the pulse-labeled cells that assumed that in any population of cells there were subpopulations in which there were zero, one, or two replicating chromosomes. This analysis predicted an average time for chromosome replication and for the period between completion of rounds of chromosome replication and division of 55 and 43 min, respectively, which were in excellent agreement with estimates made by other techniques. The present investigation extended past studies in indicating that the initiation and completion of rounds of chromosome replication are poorly phased with increases in cell volume and that the amount of chromosome replication may be different in different cell halves.