The genetic code is the set of rules used by living cells to translate information encoded within genetic material into proteins. Translation is accomplished by the ribosome, which links amino acids in an order specified by messenger RNA, using transfer RNA molecules to carry amino acids and to read the mRNA three nucleotides at a time; the genetic code is similar among all organisms and can be expressed in a simple table with 64 entries. The code defines. With some exceptions, a three-nucleotide codon in a nucleic acid sequence specifies a single amino acid; the vast majority of genes are encoded with a single scheme. That scheme is referred to as the canonical or standard genetic code, or the genetic code, though variant codes exist. While the "genetic code" is what determines a protein's amino acid sequence, other genomic regions determine when and where these proteins are produced according to various "gene regulatory codes". Efforts to understand how proteins are encoded began after DNA's structure was discovered in 1953.
George Gamow postulated that sets of three bases must be employed to encode the 20 standard amino acids used by living cells to build proteins, which would allow a maximum of 43 = 64 amino acids. The Crick, Brenner and Watts-Tobin experiment first demonstrated that codons consist of three DNA bases. Marshall Nirenberg and Heinrich J. Matthaei were the first to reveal the nature of a codon in 1961, they used a cell-free system to translate a poly-uracil RNA sequence and discovered that the polypeptide that they had synthesized consisted of only the amino acid phenylalanine. They thereby deduced; this was followed by experiments in Severo Ochoa's laboratory that demonstrated that the poly-adenine RNA sequence coded for the polypeptide poly-lysine and that the poly-cytosine RNA sequence coded for the polypeptide poly-proline. Therefore, the codon AAA specified the amino acid lysine, the codon CCC specified the amino acid proline. Using various copolymers most of the remaining codons were determined.
Subsequent work by Har Gobind Khorana identified the rest of the genetic code. Shortly thereafter, Robert W. Holley determined the structure of transfer RNA, the adapter molecule that facilitates the process of translating RNA into protein; this work was based upon Ochoa's earlier studies, yielding the latter the Nobel Prize in Physiology or Medicine in 1959 for work on the enzymology of RNA synthesis. Extending this work and Philip Leder revealed the code's triplet nature and deciphered its codons. In these experiments, various combinations of mRNA were passed through a filter that contained ribosomes, the components of cells that translate RNA into protein. Unique triplets promoted the binding of specific tRNAs to the ribosome. Leder and Nirenberg were able to determine the sequences of 54 out of 64 codons in their experiments. Khorana and Nirenberg received the 1968 Nobel for their work; the three stop codons were named by discoverers Richard Charles Steinberg. "Amber" was named after their friend Harris Bernstein.
The other two stop codons were named "ochre" and "opal". In a broad academic audience, the concept of the evolution of the genetic code from the original and ambiguous genetic code to a well-defined code with the repertoire of 20 canonical amino acids is accepted. However, there are different opinions, concepts and ideas, the best way to change it experimentally. Models are proposed that predict "entry points" for synthetic amino acid invasion of the genetic code. Since 2001, 40 non-natural amino acids have been added into protein by creating a unique codon and a corresponding transfer-RNA:aminoacyl – tRNA-synthetase pair to encode it with diverse physicochemical and biological properties in order to be used as a tool to exploring protein structure and function or to create novel or enhanced proteins. H. Murakami and M. Sisido extended some codons to have five bases. Steven A. Benner constructed a functional 65th codon. In 2015 N. Budisa, D. Söll and co-workers reported the full substitution of all 20,899 tryptophan residues with unnatural thienopyrrole-alanine in the genetic code of the bacterium Escherichia coli.
In 2016 the first stable semisynthetic organism was created. It was a bacterium with two synthetic bases; the bases survived cell division. In 2017, researchers in South Korea reported that they had engineered a mouse with an extended genetic code that can produce proteins with unnatural amino acids. In May 2019, researchers, in a milestone effort, reported the creation of a new synthetic form of viable life, a variant of the bacteria Escherichia coli, by reducing the natural number of 64 codons in the bacterial genome to 59 codons instead, in order to encode 20 amino acids. A reading frame is defined by the initial triplet of nucleotides, it sets the frame for a run of successive, non-overlapping codons, known as an "open reading frame". For example, the string 5'-AAATGAACG-3', if read from the first position, contains the codons AAA, TGA, ACG; every sequence can, thus, be read in its 5' → 3' direction in three reading frames, each producing a di
The History of local government in Scotland is a complex tale of ancient and long established Scottish political units being replaced after the mid 20th century by a changing series of different local government arrangements. Anciently, the territory now referred to as Scotland belonged to a mixture of Brythionic groups and Angles; the Picts were based north of the Forth-Clyde line, traditionally in 7 kingdoms: Cat Ce Circinn Fib Fotla Fortriu Fidach. In legends, the legendary founder of Scotland had seven sons, who each founded a kingdom. De Situ Albanie enumerates the kingdoms in two lists, the first of which locates the seventh kingdom between the Forth and the Earn, while the second additionally replaces Cat with the area that became Dalriada; the Cumbrians were based in the south west, in two principal kingdoms: Rheged StrathclydeThe Angles were based in the south east, in the Kingdom of Northumbria, divided into a number of sub-kingdoms, some of which were located in territory now considered part of Scotland: Lothian Bernicia When the Irish group Scotii invaded, they established the Kingdom of Dál Riata in the area between Glen Coe and Loch Long, which they organised into four geographic kin-groups: Cenél nÓengusa Cenél Loairn Cenél nGabráin Cenél Comgaill For reasons which are opaque to historical enquiry, most of the Pictish lands became a Scotii kingdom based at Scone - the Kingdom of Alba.
The status of Fortriu and Dalriada are unclear. The other Pictish kingdoms were divided up, with the King of Alba retaining the more useful coastal parts, while handing the remainder of each former kingdom to a powerful governor; the king controlled his lands through a number of stewards, hence the powerful governors were great stewards. Northumbrian pressure caused Rheged to collapse. Strathclyde took the opportunity created by Rheged's collapse to expand towards the south east, into what is now northern Cumbria. Records are unclear, but it seems that Scotii raids lead to Galloway submitting to the authority of Alba, the transfer of Carrick from Strathclyde to Galloway. Danish invasions caused the power of Northumbria to collapse, its lands to become parts of a unified England. Meanwhile, Norse invasions of the islands to the north and west of the mainland conquered Cat, established: Norðreyjar, divided into: Shetland Orkney Caithness Sutherland Suðreyjar Norse invaders besieged Dumbarton Rock, the capital of Strathclyde causing its defeat.
As a result, Dunbarton Rock was abandoned, Strathclyde moved its capital upriver, to Partick. Alba took the opportunity to seize the now-undefended area around Loch Lomond; the weakening of Northumbria enabled Alba to push south and take over the area around Stirling. By the 10th century, the governance of the area now known as Scotland thus broke down as follows: In the medieval period, government combined traditional kinship-based lordships with a small system of royal offices; until the 15th century the ancient pattern of major lordships survived intact, with the addition of two new "scattered earldoms" of Douglas and Crawford, thanks to royal patronage after the Wars of Independence in the borders and south-west. The dominant kindred were the Stewarts, their acquisition of the crown, a series of internal conflicts and confiscations, meant that by around the 1460s the monarchy had transformed its position within the realm, gaining control of most of the "provincial" earldoms and lordships.
Rather than running semi-independent lordships, the major magnates now had scattered estates and occasional regions of major influence. In the lowlands the crown was now able to administer government through the system of sheriffdoms and other appointed officers, rather than semi-independent lordships. In the highlands James II created two new provincial earldoms for his favourites: Argyll for the Campbells and Huntly for the Gordons, which acted as a bulwark against the vast Lordship of the Isles built up by the Macdonalds. James IV resolved the Macdonald problem by annexing the estates and titles of John Macdonald II to the crown in 1493 after discovering his plans for an alliance with the English; the shires of Scotland have their origins in the sheriffdoms or shires over which a sheriff exercised jurisdiction. The term shire is somewhat misleading. In medieval Latin, the latter was referred to as a comitatus, Scotland was the region controlled as a province or lordship, such as a mormaerdom, or an early Earldom, survived as a regality.
Shire instead came into use, in Scotland, to refer to the region in which a particular sheriff operated
Vithal Venkatesh Kamat is an Indian hotelier and environmentalist, Executive Chairman and Managing Director of Kamat Hotels Group Limited. He was born to Venkatesh Kamat in Mumbai, his father worked as a busboy. In 1952 he opened his first restaurant'Satkar'. Vithal joined his father in 1970 and is now the Chairman of Asia’s first Ecotel hotel "The Orchid", he learnt the hotel business skills there. After returning to India he started with the basic principles of green development, opened India's first Ecotel hotel "The Orchid", he visits faculty at BITS Pilani and many management institutes in India and abroad. In 1984 Kamat changed its name to Kamat Plaza, he planted more than 60 lakh trees and transformed over 100 acres of hillock into medicinal plants and local trees for forestation. He is credited with constructing the first Butterfly Garden in Mumbai and other gardens across Mumbai and Navi Mumbai, in addition to the Child Gives Birth to a Mother monuments erected in various parts of the country.
Kamat is involved with more than 1200 Advance Locality Management for maintaining clean and hygienic streets in India. His annual practices include the conversion of over 100 tons of ‘Nirmalya’ into manure after the Ganapati immersions in Mumbai; as a conservationist and an ornithologist by nature, he has created ‘Raghu–Chivu Galli’ in Mumbai and procreation of Turtle Eggs in Konkan and Orissa, the conservation of deer near Fort Jadhavgadh, Pune. He is in the process of setting up a ‘Dolphin Observatory Centre’ in Chilika Lake, Orissa. A keen Antiquarian with a collection of over 35,000 exhibits, Kamat has set up ‘Aai’ - The ‘Mother Museum’ in Mumbai and Fort Jadhavgadh, Pune. Kamat is a fine art collector who collects artifacts and antiquities from across the country. Kamat opened, his Churchgate residence has 11,000 turtle artifacts. He owns India's first museum hotel - Fort Jadhavgadh. Kamat received more than 110 national and international awards that includes Best CEO of Industry Award by The Indian Express, Golden Peacock Award received from the Dalai Lama, Lifetime Achievement Award 2012 in Germany, Green Hotelier Award 2010, Rajiv Gandhi Environment Award 2010, Golden Peacock Environment Management Award 2010 by Ola Ullsten.
He serves as President of the Maharashtra Economic Development Council, Vice President of the Hotel and Restaurant Association of Western India, Member of the Priyadarshini Academies Global Award Advisory Committee, Chairman of the Technical Education Mumbai Board to name a few. Yash Apyash Aani Mi, ISBN 9789385223624 Idli Orchid & Will Power, ISBN 9789383359158