A colony of genetically identical E. coli bacteria is actually a mob of individuals.
Dr. Michael Elowitz, Physicist at California Institute of Technology has conducted experiments on colonies of genetically identical (clones) E. coli bacteria under identical conditions and discovered that they behave in different ways.
The key to understanding E. coli’s fingerprints is to recognize that the bacteria are not simple machines. Unlike wires and transistors, E. coli’s molecules are floppy, twitchy and unpredictable. In an electronic device, like a computer or a radio, electrons stream in a steady flow through the machine’s circuits, but the molecules in E. coli jostle and wander. When E. coli begins using a gene to make a protein, it does not produce a smoothly increasing supply. It spurts out the proteins in fits and starts. One clone may produce half a dozen copies of a protein in an hour, while a clone right next to it produces none.
Michael Elowitz, a physicist at Caltech, put these bursts on display in an elegant experiment. He and his colleagues incited E. coli to produce its proteins for feeding on lactose. Dr. Elowitz and his colleagues added extra genes to the bacteria so that when they made lactose-digesting proteins, they also released light.
The bacteria, Dr. Elowitz found, did not produce a uniform glow. They flickered, sometimes brightly, sometimes dimly. And when Dr. Elowitz took a snapshot of the colony, it was not a uniform sea of light. Some microbes were dark at that moment while others shone at full strength.
At the very least, E. coli’s individuality should be a warning to those who would put human nature down to any sort of simple genetic determinism. Living things are more than just programs run by genetic software. Even in minuscule microbes, the same genes and the same genetic network can lead to different fates.
The bacteria have fingerprints of their own and even when they share the same genome, they could still be identified as individuals.
The Law of Individuality:
I propose the Law of Individuality which governs all the living entities. Either with the same and identical genome or with different genomes, all living organisms have no choice other than that of living as ‘Individuals’. The genes and the genetic codes function in accordance with the Law of Individuality. While the genetic structural organization is the same, there is functional variability due to factors over which the organism has no control. I describe Individuality as a Trade Mark. It is the characteristic of a biological entity. Genes and the genetic codes are the tools that an organism uses to express its Individuality. Each organism assembles its own kind of protein molecules to define its identity and to defend its existence in the natural world. The concept of Biological Individual and Individuality has to be always defined in the context of the Individual’s relationship with its own Body, Social Group, Society, Time, and the Environment in which the Individual finds the reality of its own Existence.