A CONSTANT RATE OF SPONTANEOUS MUTATION IN DNA-BASED MICROBES
A CONSTANT RATE OF SPONTANEOUS MUTATION IN DNA-BASED MICROBES
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DOI：
10.1073/pnas.88.16.7160
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发表时间：
1991-08-01
影响因子：
11.1
通讯作者：
DRAKE, JW
中科院分区：
文献类型：
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作者：
DRAKE, JW
就进化和适应性而言，最显著的自发突变率可能是整个基因组（或其非无关紧要的部分）的突变率。现在已经有信息可以计算几种基于DNA的单倍体微生物的这个速率，包括具有单链或双链DNA的噬菌体、细菌、酵母和丝状真菌。它们的基因组大小相差几乎等于6500倍。它们每个碱基对的平均突变率相差几乎等于16000倍，而每个基因组的突变率相差几乎等于2.5倍，显然是随机的，每次DNA复制的平均值约为0.0033。每个碱基对的平均突变率与基因组大小成反比。因此，一个几乎不变的微生物突变率似乎已经进化。因为这个速率在如此多样化的生物体中是一致的，它很可能是由深层的普遍力量决定的，也许是由突变通常的有害影响和进一步降低突变率的生理代价之间的平衡决定的。
In terms of evolution and fitness, the most significant spontaneous mutation rate is likely to be that for the entire genome (or its nonfrivolous fraction). Information is now available to calculate this rate for several DNA-based haploid microbes, including bacteriophages with single- or double-stranded DNA, a bacterium, a yeast, and a filamentous fungus. Their genome sizes vary by almost-equal-to 6500-fold. Their average mutation rates per base pair vary by almost-equal-to 16,000-fold, whereas their mutation rates per genome vary by only almost-equal-to 2.5-fold, apparently randomly, around a mean value of 0.0033 per DNA replication. The average mutation rate per base pair is inversely proportional to genome size. Therefore, a nearly invariant microbial mutation rate appears to have evolved. Because this rate is uniform in such diverse organisms, it is likely to be determined by deep general forces, perhaps by a balance between the usually deleterious effects of mutation and the physiological costs of further reducing mutation rates.