Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Minireview cung cấp cho các bạn kiến thức về ngành y đề tài: On the evolution of the standard amino-acid alphabet. | Opinion On the evolution of the standard amino-acid alphabet Yi Lu and Stephen Freeland Address Department of Biological Sciences University of Maryland Baltimore County Baltimore MD 21250 USA. Correspondence Stephen Freeland. Email freeland@ Published I February 2006 Genome Biology 2006 7 I02 doi gb-2006-7-I-I02 The electronic version of this article is the complete one and can be found online at http 2006 7 I I02 2006 BioMed Central Ltd Abstract Although one standard amino-acid alphabet is used by most organisms on Earth the evolutionary cause s and significance of this alphabet remain elusive. Fresh insights into the origin of the alphabet are now emerging from disciplines as diverse as astrobiology biochemical engineering and bioinformatics. At the root of biology there are a handful of biochemical standards the ubiquity of which tempts us to take them for granted. One is the standard alphabet of 20 encoded amino acids shared by organisms that diverged as early as Escherichia coli and human beings. But numerous lines of evidence from abiotic chemistry to protein engineering combine to indicate that this alphabet could potentially have consisted of fewer more or just plain different amino acids. So why have these 20 become the standard alphabet Extensive scientific research has explored both the order by which amino acids entered the primordial genetic code and the ways in which variations of the alphabet affect the structure and function of proteins. But knowing the history of the alphabet s formation and appreciating the high tolerance of protein structures for alternative constituents merely highlights the deeper question of the alphabet s cause. New research from synthetic biology 1 2 genomic analysis 3 and computational biochemistry 4 5 is shedding new light on the question. Greater understanding in this area would potentially help scientific adventures as diverse as the search for extraterrestrial life and the drive to .
