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INFORMATIONAL INVARIANT. “The genetic code that defines the rules of translation from the 4-letter nucleic acid alphabet to the 20-letter alphabet of proteins is arguably the single central informational invariant of all life forms.” http://www.mdpi.com/2075-1729/7/2/22/htm View in LinkedIn

NOT THE WHOLE STORY. “The frozen accident can be considered the default theory of code evolution because it does not imply any specific interactions between amino acids and the cognate codons or anticodons, or any particular properties of the code.” http://www.mdpi.com/2075-1729/7/2/22/htm View in LinkedIn

THE FROZEN ACCIDENT. “Nearly 50 years ago, Francis Crick propounded the frozen accident scenario for the evolution of the genetic code along with the hypothesis that the early translation system consisted primarily of RNA. Under the frozen accident perspective, the code is universal among modern life forms because any change in codon assignment would be highly deleterious.” https://lnkd.in/dKTqJpY View in LinkedIn

FRAGMENT FROM NATURE for this and next weekend focuses on the (nearly) universal genetic code, that dominates the inheritance of life on earth, and how four letters encodes twenty letters of protein with millions upon millions of functional variants based on conformation. And although widely perceived as an elegantly designed Blueprint, in fact it is a mishmash of accidents. While the dominant genetic code, Nature, as always, has variants up its sleeve. View in LinkedIn

BEYOND EXPERIMENTS. "The assembly or emergence of life, given that the right building blocks do exist, is still out of the scope of experimental chemistry." https://scholar.google.es/scholar?start=50&q=artificial+chemistry&hl=en&as_sdt=0,5&as_vis=1 View in LinkedIn

ORIGIN OF LIFE. "An important open question is whether investigating such a random chemistry setting in the test tube is within the capabilities of current chemistry techniques. What is required is a capacity to handle the high number of molecular species, each potentially at low concentration, in very large volumes and for extremely long periods of time." http://www.weizmann.ac.il/molgen/Lancet/sites/molgen.Lancet/files/uploads/shenhav_lancet_core.pdf View in LinkedIn

BIOTRANSITION FROM THE INANIMATE. "The question "How does life arise from the nonliving?" is first on the list of open problems in artificial life." We do love this grey zone, it appears. https://scholar.google.es/scholar?start=50&q=artificial+chemistry&hl=en&as_sdt=0,5&as_vis=1 View in LinkedIn

ROTAXANE. "Scientists in the UK and Malaysia have created a self-assembling rotaxane that can replicate itself. The result may lead to the development of autonomous chemical systems that mimic cellular processes." http://www.rsc.org/chemistryworld/2015/11/self-replicating-assembly-rotaxane-dna-1 View in LinkedIn

SELF-REPLICATING MOLECULES. "He mentioned three specific groups of scientists, including his group, that have created self-replicating molecules, and indicated that there are others. I asked him if these were derived from naturally occurring self-replicating molecules, and he said that none of the molecules were derived from naturally occurring molecules." https://lnkd.in/d9-rKhE View in LinkedIn

SELECTIVE PRESSURES. “The genetic code is not quite universal. The rare variations that we know of reveal selective pressures on the code and on the translation machinery. New data suggest the code changes through ambiguous intermediates and that termination is context dependent.“ https://www.sciencedirect.com/science/article/pii/S0960982216309174 View in LinkedIn