Poet writes verse in bug's genes and receives reply
An original piece of "living poetry" has been created in a lab in Canada.
Poet Christian Bok has encoded his verse into a strip of DNA and had it inserted into a common bacterium, E.coli.
DNA is at the heart of every cell. It is a string of molecules called nucleotides which come in four types - adenine (A), guanine (G), cytosine (C) and thymine (T).
This genetic sequence is used as an instruction manual for cellular operations. Individual commands are contained in shorter chunks of the DNA called genes.
Dr Bok used cryptography to embed his poem into the genetics of the bacterium, devising a chemical alphabet in which each letter is represented by a specific triplet of nucleotides. So, for example, the nucleotide sequence "ATA" codes for the letter "y" and GTG stands for the letter "n".
It took him four years just to work out the code.
This enabled him to design a novel gene called X-P13, which was constructed specifically for the project. The poem's opening words, "Any style..." translate as ACG(A) GTG(n) ATA(y) AGT(space) AAG(s) TGC(t) ATA(y) GCC(l) TAT(e) in his gene's DNA sequence.
Dr Bok has no formal scientific training, but he taught himself molecular biology and computer programming for the purpose of this project. His design was verified by biologists at the University of Calgary.
Similar biochemical feats have been achieved before. American scientist Dr Pak Wong encoded the lyrics to It's a Small World After All into a strand of DNA and lodged it inside the bacterium Deinococcus radiodurans.
And when Dr Craig Venter, of the J Craig Venter Institute (JCVI) in Maryland and California, created the world's first manmade bacterial genome, he embedded his own name and those of his colleagues into its DNA; alongside quotes from James Joyce and from the Nobel prize winning physicist Richard Feynman.
But Dr Bok, who teaches in the department of English at the University of Calgary, has gone one step further than just encoding his ode into DNA: he has induced his laboratory bacterium to give its own bio-poetry response.
Cells use their DNA as a template for constructing proteins, which are strings of molecules called amino acids.
The exact sequence of nucleotides within a gene dictates the order of the amino acids, because a specific triplet of nucleotides will serve as the command to attach a particular amino acid at that point. For example an ACG in the gene, means 'use the amino acid threonine next'.
Dr Bok's chemical cryptography is designed to work on two levels. Not only did he devise a cipher to link letters of the alphabet to specific nucleotides, but he also designed a second cipher to allow the ensuing protein to be decoded back into a brand new poem, by assigning a different set of letters to specific amino acids.
For example his first poem's opening words "Any style", once encoded into DNA, instructs the cell to build a protein that starts with the following amino acid string: threonine, valine, isoleucine, serine, lysine, cysteine, isoleucine, alanine, tyrosine, which can in turn be decoded to spell out the start of the bacterium's new poetic response "The faery..."
His scientific collaborator at the University of Calgary, Professor Sui Huang, confirmed that their lab has now succeeded in implanting the poem gene as a free floating chunk of DNA into E. coli and witnessed the bug express its own poetic protein response.
Dr Bok's next ambition for his Xenotext project is to create a literary work that will outlast humanity, by splicing X-P13 directly into the genome of the D. radiodurans bacterium.
Known as "Conan the bacterium" for its durability, this extremophile is the world's toughest organism, able to resist radiation, cold, dehydration and acid.
His hope is that once embedded into the genetics of D. radiodurans, his biochemical text could continue to reproduce for billions of years - outlasting any other human artefact. Although he has no intention of releasing it into the wild.
He explained his aims. "Nothing we humans make will last more than a few million years," he said.
"The only legacy we will leave is the background radiation of nuclear waste and the ecological and geological effects of climate change and that is not an appropriate one. By genetically engineering a poem into Deinococcus radiodurans I am producing something that will last over epochal time".
But Dr Julian Parkhill of the Wellcome Trust Sanger Institute was sceptical of the chances for literary immortality. "His poem would be rapidly removed by natural selection, as it would confer no benefit on the host bacterium," he said. "Natural selection as literary criticism".
Professor Huang conceded that this is a very real possibility. "If the poem protein conveys even a slight disadvantage on the bacterium, the gene could be kicked out over time," he said.
"We don't know what the selection pressure would be for it to be kept, if it isn't too much of a burden the gene might stay".
And he argued that there was a scientific value to the project. "It shows how biology is just like information science," he said.
"There is already a poetry to nature and I see a parallel with the Xenotext project"
Dr Bok will be talking about his project and displaying the text of the two poems at the UK's Bury Text Festival on Saturday 30 April.