Mutant number distribution in an exponentially growing population

Mutant number distribution in an exponentially growing population

We present an explicit solution to a classic model of cell-population growth introduced by Luria and Delbrück [1] 70 years ago to study the emergence of mutations in bacterial populations. In this model a wild-type population is assumed to grow exponentially in a deterministic fashion. Proportional to the wild-type population size, mutants arrive randomly and initiate new sub-populations of mut...

Fitness distributions in exponentially growing asexual populations.

We explore a mean-field model for the evolution of exponentially growing populations of mutating replicators. Motivated by recent in vitro experiments devised to analyze phenotypic properties of bacterial and viral populations subjected to serial population transfers, we allow our in silico individuals to undergo unrestricted growth before applying bottleneck events. Different dynamical regimes...

Population Genetics of Neutral Mutations in Exponentially Growing Cancer Cell Populations.

In order to analyze data from cancer genome sequencing projects, we need to be able to distinguish causative, or "driver," mutations from "passenger" mutations that have no selective effect. Toward this end, we prove results concerning the frequency of neutural mutations in exponentially growing multitype branching processes that have been widely used in cancer modeling. Our results yield a sim...

The Number of Mutant Forms Maintained in a Population

Metabolism of individual proteins in exponentially growing Escherichia coli.

The metabolism of 184 individual proteins was examined in exponentially growing Escherichia coli. Cells were labeled with [3H]leucine and [35S]methionine using either a pulse-chase or a continuous labeling method. Proteins were fractionated by two-dimensional gel electrophoresis and their stabilities relative to total protein were determined from the 3H/35S ratios. Forty-seven proteins appeared...