An integron is a type of transposon, a mobile genetic element. It is a two-part genetic system found in bacteria, and maybe more widely. It is the way antibiotic resistance is passed on so rapidly. It is found in plasmids and chromosomes. Although the first function discovered was antibiotic resistance, other bacterial functions (traits) can be transferred by integrons.
Transposons are the gene "capture and expression elements" which put the small mobile elements known as gene cassettes in place and make them work. Usually,
each cassette has only a single gene and a specific
recombination site. The cassettes carry the DNA coding (= 'a gene') for antibiotic resistance (for example). Typically, the DNA would code for an enzyme which cleaves (cuts) the antibiotic molecule up.
The first part of an integron is a gene which codes for an enzyme which captures cassettes. The second is a site on the genome where the cassettes are inserted, and a promoter which drives expression of cassette-associated genes. "Integron" describes such structures both when no cassettes are present and when there are integrated cassettes. Cassettes can be inserted at the site, they can be cut out, and they can undergo horizontal gene transfer.
Philip Short
Philip Short (born on 17 April 1945) is an English journalist. He studied at Queens' College, Cambridge. After his graduation, he spent from 1967 to 1973 as a freelance journalist, first in Malawi, then in Uganda. He then joined the BBC (British Broadcasting Corporation) as a foreign correspondent. He is an author of many books, such as biographies of Mao Zedong, "Mao: A Life", and of Pol Pot, "Pol Pot: Anatomy of a Nightmare".
Pointless (game show)
Pointless is a British quiz show on BBC One. Who gets the answer that was the said the least gains the point. The team with the highest number of points loses. It is presented by Alexander Armstrong and Richard Osman. It now has 10 series and many episodes. In each game there are four teams of two.
William Marshal, 1st Earl of Pembroke
William Marshal, 1st Earl of Pembroke (1147 – 14 May 1219), sometimes called William, the Marshal or "the Marshal", was an "English" Knight who served five Kings. He was Regent of England for a time during the childhood of Edward III. In his day he may have been one of the most important persons in the monarchy next to the Royal family itself. He was noted for his superior combat skills, his continuing loyalty to his Kings and his great ability in diplomacy. Marshal began his life as a “landless” knight to become the Earl of Pembroke and one of the wealthiest men in the country.
Shortly after his death in 1219, his oldest son, William Marshal II, commissioned a biography of the life of his father. Though biographers often embellish their subjects, many of the events of William's life stated there are clearly recorded elsewhere in historical records.
William Marshal’s father, was John Marshal, called John the Marshal. He was the Lord of Newbury Castle located in County Berkshire in England. When William was a young boy, there was a fierce civil war in England between King Stephen, grandson of William I, also called William the Conqueror and Henry I's daughter, Empress Matilda. When William I died, both Stephen and Matilda believed they were the true successor to the Crown. This period in history was known as the time of The Anarchy because there was much lawlessness and violence in the Kingdom. Many barons and Earls would "change sides" when it benefited them to do so and John Marshal was no exception. At first he pledged his fealty or loyalty to King Stephen but later changed it to Empress Matilda. This act helped to turn the tide in the civil war.
At an early age, William was sent to William de Tancarville to learn the skills of knighthood. He was knighted in 1166. He then crossed the channel to Normandy and went to serve under his uncle, Patrick, the Earl of Salisbury. He fought in Ponthieu in 1168 when greatly outnumbered, his uncle was killed and William was taken prisoner. Marshal's great skill and bravery was noticed and he was ransomed by Queen Eleanor of England.
As a young adult, Marshal went to many tournaments. These were contests and mock (imitation) wars where Knights competed for great prizes. Tournaments were an opportunity for a knight to acquire valuable possessions such as money, a horse, armor and weapons. They were dangerous and it was not unusual for a knight to be killed during a tournament.
William had become a very skilled knight and after his ramsom he became part of Henry II’s household, teaching men to fight. He became tutor, guardian, protector and friend to the son of Henry II, known historically as Henry the Young King. When young Henry was coronated, Marshal was assigned to serve him as captain of the guard and chief of the knights. It was Marshal who would knight the young King Henry. Marshal also accompanied young Henry on many tournaments. In 1173 young Henry argued with his father. He wanted to assume the throne of England even though his father was still alive. He left England and took his brother Richard with him to his mother's lands in Aquitaine. In 1174, Henry II and his son made peace. William continued on to win fame in tournaments. The young king became ill and died of a sudden disease at Martel on 11 June 1183.
On his deathbed young Henry ordered Marshal to go on Crusade on his behalf. With Henry II's permission, William went on Crusade for two years and his superior fighting skill was recognized by the Knights Templar. When he returned, Henry II at once took him into high favor, and made him a member of his household. Marshal then fought for Henry II against the French King Louis VII of France and in skirmishs against Henry's other sons now in rebellion.
Richard (called Lionhearted) was Henry II’s second son and he also wanted to be King of England and did not want to wait until his father died. After a skirmish, Marshal came upon Richard and instead of killing him, killed his horse. Shortly thereafter, Henry II became ill and retreated to Chinon where he died in 1189.
Richard did not forget Marshal’s act of bravery and loyalty and when he became King, he took Marshal to fight against the King of France. After a time, Richard decided to go on Crusade and left Marshal in England as the Justiciar of England who acted for the king in his absence and presided over the king's courts during his absence.
Richard I reaffirmed his father's promise to William and gave him the heiress of the Earldom of Pembroke, Striguil and the lands that came with her as was promised to him by Henry II shortly before Henry's death. Marshal at once became one of the richest men in the Kingdom. He acquired property in four countries.
Marshal fought valiantly for Richard against the King of France and was there when the peace treaty was made. In 1199 King Richard was wounded and died of his wounds. At that point there was another dispute about who would next be King of England, Arthur or John.
Geoffrey II, Duke of Brittany, was another son of Henry II and would have been the next in line to be King but he died on either the 19 or 21 August 1186, at the age of 27. The more common version is that he was trampled to death in a jousting tournament. Geoffrey had a son Arthur I, who became the next Duke of Brittany. Arthur felt that he was also heir to the throne of England. Marshal believed that as a brother to King Richard, and in accordance with Norman custom, John, Geoffrey’s brother, should become the next King. It was resolved in John’s favor and he became the next King of England.
William fought alongside King John and after a time, John made William the Marshal of England.