Year: 2022

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

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

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

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

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

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

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

DEVIATIONS. “The genetic code is nearly universal in all extant life forms although limited deviations from the standard genetic code have been detected in many groups of organisms, particularly in organelles and parasitic or endosymbiotic bacteria with highly reduced genomes.” http://www.mdpi.com/2075-1729/7/2/22/htm View in LinkedIn

UNIVERSAL STRUCTURE. “Indeed, notwithstanding multiple code variants that continue to emerge through the study of protein coding in diverse life forms, the basic structure of the code and the majority of the codon assignments are truly universal.” http://www.mdpi.com/2075-1729/7/2/22/htm View in LinkedIn

ERROR PROTECTION. “The code is robust to error, i.e., mutational and translation errors in synonymous positions (typically, the third position in a codon) have no effect on the protein, whereas substitutions in the first position typically lead to incorporation of an amino acid similar to the correct one, thus decreasing the damage.” http://www.mdpi.com/2075-1729/7/2/22/htm View in LinkedIn