crème de la crème

Jai Ganesh · 2025-02-16 16:13:54

2164) Paul L. Modrich

Gist:

Life

Paul Modrich was born and raised in Raton, New Mexico, USA. His father was a biology teacher and encouraged his curiosity in nature. Modrich received his doctorate at Stanford University in 1973 and also studied at the Massachusetts Institute of Technology. Since 1976 he works at Duke University, Durham, North Carolina. He is also affiliated with Howard Hughes Medical Institute, Chevy Chase, Maryland.

Work

Living cells have DNA molecules that carry an organism's genes. For the organism to live and develop, its DNA cannot change. DNA molecules are not completely stable, and they can be damaged. In 1989, through studies of bacterial viruses, Modrich showed how methyl groups attached to the DNA molecule act as signals for repairing incorrect replications of DNA. These discoveries have increased our understanding of how the living cell works, the causes of cancer and about aging processes.

Summary

Paul Modrich (born 1946, Raton, New Mexico, U.S.) is an American biochemist who discovered mismatch repair, a mechanism by which cells detect and correct errors that are introduced into DNA during DNA replication and cell division. Modrich was among the first to show that a common form of inherited colorectal cancer is due to defective mismatch repair. For his contributions to the understanding of DNA repair and its role in human disease, Modrich received the 2015 Nobel Prize for Chemistry (shared with Swedish biochemist Tomas Lindahl and Turkish-American biochemist Aziz Sancar).

Modrich received a bachelor’s degree in biology in 1968 from the Massachusetts Institute of Technology and a Ph.D. in biochemistry in 1973 from Stanford University. In 1976, following postdoctoral studies at Harvard Medical School, he went to Duke University, where he joined the faculty as an assistant professor, and in 1988 he was named James B. Duke Professor of Biochemistry.

As a graduate student at Stanford, Modrich investigated an enzyme called ligase and its ability to catalyze the joining together of nucleotides in the DNA of the bacterium Escherichia coli. He found that ligase enzymes are essential to normal DNA synthesis in E. coli and hence are fundamental to the bacterium’s survival. In the late 1970s, intrigued by DNA lesions and the process of DNA replication, Modrich began to examine base-pair mismatches in E. coli DNA that are acquired during homologous recombination (the exchange of genetic material between two identical or nearly identical strands of DNA during DNA replication). By the early 1980s he had developed an assay to analyze mismatched base pairs. The development facilitated his subsequent identification and characterization of proteins and events involved in methyl-directed mismatch repair in E. coli, in which the absence of methyl groups on newly synthesized daughter strands of DNA serves as the signal for the initiation of mismatch repair.

In the early 1990s Modrich described the excision mechanism by which mismatched DNA is targeted and eliminated in E. coli cells. He also elucidated the mechanism of mismatch repair in human cells, revealing key similarities to the mechanism used by bacteria. He later uncovered a role for mismatch repair deficiency in hereditary nonpolyposis colon cancer (Lynch syndrome)—the most prevalent type of hereditary colorectal malignancy in humans—as well as in certain neurodegenerative conditions, such as Huntington disease.

Modrich was elected to the U.S. National Academy of Sciences in 1993 and the following year became a Howard Hughes Medical Institute Investigator. He was a fellow of the American Academy of Arts and Sciences from 2004.

Details

Paul Lawrence Modrich (born June 13, 1946) is an American biochemist, James B. Duke Professor of Biochemistry at Duke University and Investigator at the Howard Hughes Medical Institute. He is known for his research on DNA mismatch repair. Modrich received the Nobel Prize in Chemistry 2015, jointly with Aziz Sancar and Tomas Lindahl.

Early life and education

Modrich was born on June 13, 1946, in Raton, New Mexico to Laurence Modrich and Margaret McTurk. He has a younger brother Dave. His father was a biology teacher and coach for basketball, football and tennis at Raton High School where he graduated in 1964. Modrich is of Croatian, Montenegrin, German and Scottish (Gaelic)]origin. His paternal grandfather, of Croatian descent, is probably from the small village of Modrići near Zadar, and grandmother of Montenegrin descent, both immigrated to the United States from coastal Croatia in the late 19th century. His maternal family is of mixed German and Scotch-Irish descent. Modrich married fellow scientist Vickers Burdett in 1980.

Modrich obtained a B.S. degree from the Massachusetts Institute of Technology in 1968 and subsequently a Ph.D. degree from Stanford University in 1973. He continued his research as a postdoc in the lab of Charles C. Richardson at Harvard Medical School for a year (1973–1974).

Research

Modrich became an assistant professor at the chemistry department of University of California, Berkeley in 1974. He joined Duke University's faculty in 1976 and has been a Howard Hughes Investigator since 1995. He works primarily on strand-directed mismatch repair. His lab demonstrated how DNA mismatch repair serves as a copyeditor to prevent errors from DNA polymerase. Matthew Meselson previously proposed the existence of recognition of mismatches. Modrich performed biochemical experiments to study mismatch repair in E. coli. They later searched for proteins associated with mismatch repair in humans.

Jai Ganesh · 2025-02-17 15:40:31

2165) Aziz Sancar

Gist:

Life

Aziz Sancar was born in Savur in southeast Turkey in a lower middle class family. His parents had no education but considered education important for their children. Sancar studied at Istanbul University and at the University of Texas, Dallas, where his received his doctorate in 1977. He is a professor at the University of North Carolina School of Medicine, Chapel Hill. Aziz Sancar is married to Gwen Boles Sancar who also is a professor in biochemistry and biophysics.

Work

Living cells have DNA molecules that carry an organism's genes. For the organism to live and develop, its DNA cannot change. DNA molecules are not completely stable, and they can be damaged. In 1983, through studies of bacteria, Aziz Sancar showed how certain protein molecules, certain repair enzymes, repair DNA damaged by ultraviolet (UV) light. These discoveries have increased our understanding of how the living cell works, the causes of cancer and aging processes.

Summary

Aziz Sancar (born September 8, 1946, Savur, Mardin, Turkey) is a Turkish-American biochemist who contributed to mechanistic discoveries underlying a cellular process known as nucleotide excision repair, whereby cells correct errors in DNA that arise as a result of exposure to ultraviolet (UV) light or certain mutation-inducing chemicals. For his discoveries pertaining to mechanisms of DNA repair, Sancar received the 2015 Nobel Prize for Chemistry (shared with Swedish biochemist Tomas Lindahl and American biochemist Paul Modrich).

Sancar received an M.D. in 1969 from the Istanbul Medical School and subsequently worked as a local physician near Savur. In 1973 he went to the United States to study molecular biology at the University of Texas, Dallas, where four years later he completed a Ph.D. He then accepted a position as a research associate at Yale University and in 1982 joined the faculty at the University of North Carolina School of Medicine, where he later was named the Sarah Graham Kenan Professor of Biochemistry and Biophysics.

As a graduate student, Sancar studied an enzyme known as DNA photolyase in the bacterium Escherichia coli. At the time, the enzyme had been recently found to mediate the process of photoreactivation, whereby visible light induces enzymatic reactions that repair DNA damaged by UV irradiation. After moving to Yale, Sancar turned his attention to several other DNA repair factors in E. coli, namely the genes uvrA, uvrB, and uvrC. He purified the genes and reconstituted them in vitro (“in glass,” or outside a living organism), leading to his discovery of the excision repair function of an enzyme known as uvrABC nuclease (excision nuclease, or excinuclease) in E. coli. The enzyme specifically targeted DNA that had been damaged by UV or chemical exposure, cutting the affected DNA strand at each end of the damaged region and thereby enabling the removal of the damaged nucleotides.

Sancar and his colleagues later reconstituted a human excision nuclease, identified components required for nucleotide excision repair in human cells, and proposed that human cells employed additional enzymes in the removal of the excised portion of DNA. He also identified a role for defective nucleotide excision repair in the production of neurological abnormalities associated with xeroderma pigmentosum, a neurodegenerative condition that predisposes individuals to skin cancer. Abnormalities in nucleotide excision repair also were found to underlie other rare hereditary disorders, including math syndrome (characterized by multisystemic effects, such as dwarfism and photosensitivity) and photosensitive trichothiodystrophy (characterized by sulfur-deficient brittle hair, developmental abnormalities, and extreme sensitivity to ultraviolet light with normal skin cancer risk).

From the early 1980s Sancar continued to investigate photolyase in E. coli, and later he began to explore DNA damage checkpoints. He discovered two light-harvesting chromophores in photolyase, which he proposed were key components of the photolyase reaction mechanism and its activity at the blue end of the visible light spectrum. In the early 2000s he directly observed, for the first time, the mechanism of DNA repair by photolyase. Sancar also investigated human photolyase orthologs (genes evolutionarily related to E. coli DNA photolyase) known as cryptochrome 1 and 2. He found that the cryptochromes, which are located in the eye, function as photoreceptive components of the mammalian circadian clock.

Sancar was an elected member of multiple academies, including the American Academy of Arts and Sciences (2004), the U.S. National Academy of Sciences (2005), and the Turkish Academy of Sciences (2006).

Details

Aziz Sancar (born 8 September 1946) is a Turkish molecular biologist specializing in DNA repair, cell cycle checkpoints, and circadian clock. In 2015, he was awarded the Nobel Prize in Chemistry along with Tomas Lindahl and Paul L. Modrich for their mechanistic studies of DNA repair. He has made contributions on photolyase and nucleotide excision repair in bacteria that have changed his field.

Sancar is currently the Sarah Graham Kenan Professor of Biochemistry and Biophysics at the University of North Carolina School of Medicine and a member of the UNC Lineberger Comprehensive Cancer Center. He is the co-founder of the Aziz & Gwen Sancar Foundation, which is a non-profit organization to promote Turkish culture and to support Turkish students in the United States.

Early life

Aziz Sancar was born on 8 September 1946 to a lower-middle-class family in the Savur district of Mardin Province, southeastern Turkey. His oldest brother Kenan Sancar is a retired brigadier general in the Turkish Armed Forces. He is the second cousin of the politician Mithat Sancar, who is a member of parliament from and chairman of HDP. He is the seventh of eight children.

His parents were uneducated; however, they put great emphasis on his education. He was educated by idealistic teachers who received their education in the Village Institutes, he later stated that this was a great inspiration to him. Throughout his school life, Sancar had great academic success that was noted by his teachers. He wanted to study chemistry whilst at high school, but was persuaded to study medicine after five of his classmates also got into medicine along with him. As such, he studied medicine at the Faculty of Medicine of Istanbul University.

Origins

According to his own account, he spoke Arabic with his parents and Turkish with his siblings. However, when asked about his origins, Sancar only underlined his Turkish nationality. Still, his cousin, Mithat Sancar, mentioned that their family is of Arab origins. Aziz Sancar's brother Tahir claimed in an interview that their family descended from Oghuz Turks from Central Asia, also mentioning that they are idealists. During his years at Istanbul University, he was involved with the Turkish nationalist organization Idealist Hearths (Ülkü Ocakları).

Education

Sancar received his primary education near his hometown of Savur. He then completed his MD degree in Istanbul University of Turkey in 1969 and he graduated from school as the top student. He completed his PhD degree on the photoreactivating enzyme of E. coli in 1977 at The University of Texas at Dallas in the laboratory of Claud Stan Rupert, now Professor Emeritus.

Career

Sancar is an honorary member of the Turkish Academy of Sciences and the American Academy of Arts and Sciences.

After graduating from Istanbul University, Sancar returned to Savur. Although he wanted to go to the United States, he was recommended to try out being a doctor, and he worked as a doctor in the region for 1.5 years. He then won a scholarship from TÜBİTAK to pursue further education in biochemistry at Johns Hopkins University, but returned to Savur in 1973 as a doctor after spending 1.5 years there due to having social difficulties and inability to adapt to the American way of life. He only spoke French when he arrived in the US, but learned English during his education at Johns Hopkins.

Soon after, he wrote to Rupert, who had been involved in the discovery of DNA repair and was at Johns Hopkins during Sancar's time there but had since moved to the University of Texas at Dallas. He was accepted and completed his PhD in molecular biology there. His interest had been stimulated by the recovery of bacteria, which had been exposed to deadly amounts of ultraviolet radiation, upon their illumination with blue light. In 1976, as part of his doctoral dissertation, he managed to replicate the gene for photolyase, an enzyme that repairs thymine dimers that result from ultraviolet damage.

After completing his PhD, Sancar had three rejected applications for postdoctoral positions and then took up work at Yale University as a laboratory technician. He worked at Yale for five years. Here, he started his field-changing work on nucleotide excision repair, another DNA mechanism that works in the dark. In the laboratory of Dean Rupp, he elucidated the molecular details of this process, identifying UvrABC endonuclease and the genes that code for it, and furthermore discovering that these enzymes cut twice on the damaged strand of DNA, removing 12–13 nucleotides that include the damaged part.

Following his mechanistic elucidations of nucleotide exchange repair, he was accepted as a lecturer at the University of North Carolina, the only university that he got a positive response from out of the 50 he applied to. He has stated that his accent of English was detrimental to his career as a lecturer. At Chapel Hill, Sancar discovered the following steps of nucleotide excision repair in bacteria and worked on the more complex version of this repair mechanism in humans.

His longest-running study has involved photolyase and the mechanisms of photo-reactivation. In his inaugural article in the PNAS, Sancar captured the photolyase radicals he has chased for nearly 20 years, thus providing direct observation of the photocycle for thymine dimer repair.

Aziz Sancar was elected to the National Academy of Sciences in 2005 as the first Turkish member. He is the Sarah Graham Kenan Professor of Biochemistry, at the University of North Carolina at Chapel Hill. He is married to Gwen Boles Sancar, who graduated the same year and who is also a professor of Biochemistry and Biophysics at the University of North Carolina at Chapel Hill. Together, they founded Carolina Türk Evi, a permanent Turkish Center in close proximity to the campus of UNC-CH, which provides graduate housing for four Turkish researchers at UNC-CH, short term guest services for Turkish visiting scholars, and a center for promoting Turkish-American interchange.

Research on circadian clock

Sancar and his research team have discovered that two genes, Period and Cryptochrome, keep the circadian clocks of all human cells in proper rhythm, syncing them to the 24 hours of the day and seasons. Their findings were published in the Genes and Development journal on September 16, 2014. Sancar's research has provided a complete understanding of the workings of Circadian clocks in humans, which may be used to treat a wide range of different illnesses and disorders such as jet-lag and seasonal affective disorder, and may be useful in controlling and optimizing various cancer treatments.

Personal life

Sancar is married to Gwen Boles Sancar, with whom he met during his PhD in Dallas, where she was also studying molecular biology. They got married in 1978.

Sancar is a practicing Muslim. In an interview, he stated: "I am proud to be Muslim, but I can not state this fact in many regions of the United States due to ongoing issues." In the immediate aftermath of being awarded the Nobel Prize, his ethnicity was questioned in social media. Sancar said he was "disturbed by some of the questions he received," particularly by questions about his ethnic background. When asked as to whether he is "a Turk or half-Arab" by the BBC, Aziz Sancar responded: "I told them that I neither speak Arabic nor Kurdish and that I was a Turk," he said. "I'm a Turk, that's it." Aziz Sancar's brother Tahir informed in an interview that their family descended from Oghuz Turks who once migrated from Central Asia. He also said that his brother's Nobel Prize was an honor for all of Turkey, including the Kurds.

In an interview, Sancar stated that in his youth, he was an idealist but he didn't participate in activities. In another interview, Sancar stated that he supports moderate Pan-Turkism. On September 26, 2021, Sancar was the honorary guest of the Turkic Council on occasion of the meeting of the foreign secretaries from member states and has given a presentation titled "Knowledge and the National Awakening of the Turkic World", as announced by Turkish Minister of Foreign Affairs Mevlüt Çavuşoğlu.

Awards
He was awarded the 2015 Nobel Prize in Chemistry along with Tomas Lindahl and Paul L. Modrich for their mechanistic studies of DNA repair. He was granted Presidential Young Investigator Award from the National Science Foundation in Molecular Biophysics in 1984. Sancar is the second Turkish Nobel laureate after Orhan Pamuk, who is also an alumnus of Istanbul University.

Aziz Sancar donated his original Nobel Prize golden medal and certificate to the mausoleum of Mustafa Kemal Atatürk, with a presidential ceremony on 19 May 2016, which is the 97th anniversary of Atatürk initiating the Turkish War of Independence. He delivered a replica of his Nobel medal and certificate to Istanbul University, from which he earned his MD.

On January 19, 2025, during a ceremony held at the Sancar Cultural Center in the state of North Carolina, USA, TÜRKSOY General Secretary Sultan Raev presented Sancar with the Order of Cultural Ambassador of the Turkic World.

Jai Ganesh · 2025-02-18 16:52:26

2166) William C. Campbell (scientist)

Gist:

Life

William C. Campbell was born in Ramelton, Ireland. He studied at Trinity College at the University of Dublin and at the University of Wisconsin, Madison, USA, where he earned his doctorate in 1957. He then worked for the pharmaceutical company Merck at its Institute for Therapeutic Research until 1990. He is now affiliated with Drew University, Madison, New Jersey i USA.

Work

A number of serious infectious diseases are caused by parasites spread by insects. River blindness is caused by a tiny worm that can infect the cornea and cause blindness. Lymphatic filariasis, or elephantiasis, is also caused by a worm and produces chronic swelling. Satoshi Omura cultured bacteria, which produce substances that inhibit the growth of other microorganisms. In 1978 he succeeded in culturing a strain from which William Campbell purified a substance, avermectin, which in a chemically modified form, ivermectin, proved effective against river blindness and elephantiasis.

Summary

William Campbell (born June 28, 1930, Ramelton, Ireland) is an Irish-born American parasitologist known for his contribution to the discovery of the anthelmintic compounds avermectin and ivermectin, which proved vital to the control of certain parasitic infections in humans and other animals. For his discoveries, Campbell was awarded the 2015 Nobel Prize for Physiology or Medicine (shared with Japanese microbiologist Ōmura Satoshi and Chinese scientist Tu Youyou).

Campbell earned a bachelor’s degree in zoology from Trinity College in Dublin in 1952. He subsequently went to the United States, where he studied veterinary science, zoology, and pathology at the University of Wisconsin. In 1957, after completing a Ph.D. at Wisconsin, Campbell took a position as a research assistant at the Merck Institute for Therapeutic Research in New Jersey. There in 1976 he was made the director of basic parasitology, and from 1984 to 1990 he served as a senior scientist and directed assay research and development. Campbell became a U.S. citizen in 1962.

In the 1970s researchers at Merck & Co. received a culture of the soil bacterium Streptomyces avermitilis from Ōmura Satoshi, who had discovered the species in the course of his work at the Kitasato Institute in Japan. Preliminary experiments suggested that the organism produced a substance that was potentially lethal to certain types of parasites. In 1975, using an assay that tested compounds for activity against the infectious nematode Nematospiroides dubius in mice, Campbell and colleagues at Merck discovered avermectin, which existed as several compounds, all closely related in structure and known as macrocyclic lactones. Having purified avermectin, the Merck team subjected the compound to structural modification, ultimately producing a chemical known as ivermectin. Ivermectin was found to be active against a wide array of microfilariae (larvae) produced by certain threadlike nematode parasites. Of particular consequence was its ability to clear infections in humans involving the microfilariae of Onchocerca volvulus, the cause of river blindness, and Wuchereria bancrofti and Brugia malayi, the major causes of lymphatic filariasis (elephantiasis). Both river blindness and lymphatic filariasis were significant sources of debilitating illness in tropical regions of the world. The drug also proved critical to the prevention of certain arthropod and microfilariae-associated infections in other animals, including horses, sheep, and cattle; it also was used widely for the prevention of heartworm disease in cats and dogs.

In later research Campbell studied a variety of parasitic diseases, including trichinosis. He retired as research fellow emeritus at Drew University in New Jersey. During his career he served as the president of multiple organizations, including the American Society of Parasitologists. In addition to numerous research papers, Campbell edited two texts, Trichinella and Trichinosis (1983) and Chemotherapy of Parasitic Diseases (1986, with Robert S. Rew), which were critical to furthering the understanding of parasitic disease.

Details

William Cecil Campbell (born 28 June 1930) is an Irish-American microbiologist known for his work in discovering a novel therapy against infections caused by roundworms, for which he was jointly awarded the 2015 Nobel Prize in Physiology or Medicine. He helped to discover a class of drugs called avermectins, whose derivatives have been shown to have "extraordinary efficacy" in treating River blindness and Lymphatic filariasis, among other parasitic diseases affecting animals and humans. Campbell worked at the Merck Institute for Therapeutic Research 1957–1990, and has become a research fellow emeritus at Drew University.

Biography

Campbell was born in Ramelton, County Donegal, Ireland in 1930, the third son of R. J. Campbell, a farm supplier. He studied at Trinity College, Dublin with James Desmond Smyth, graduating in 1952 with first class honours in Zoology. He then attended the University of Wisconsin–Madison on a Fulbright Scholarship, earning his PhD degree in 1957 for work on the liver fluke, a parasite affecting sheep.

From 1957 to 1990 Campbell worked at Merck Institute for Therapeutic Research,[8] and from 1984 to 1990 he was a Senior Scientist and Director with Assay Research and Development. He became a US citizen in 1964. One of his discoveries while at Merck was the fungicide thiabendazole, used to treat potato blight, historically a scourge of Ireland. Thiabendazole is also used to treat trichinosis in humans.

Campbell is best known for his work on parasitic diseases. Japanese microbiologist Satoshi Ōmura isolated and cultured many varieties of natural soil-based bacteria from the group Streptomyces. Campbell led a team at Merck in studying Ōmura's cultures and examining their effectiveness in treating parasites in domestic and farm animals. From a sample of Streptomyces avermitilis, naturally occurring in soil, he derived a macrocyclic lactone. After further modification, it was named ivermectin (generic) or Mectizan.

In 1978, having identified a successful treatment for a type of worms affecting horses, Campbell realised that similar treatments might be useful against related types of worms that affect humans. In 1981, Merck carried out successful Phase 1 treatment trials in Senegal and France on river blindness. Taken orally, the drug paralyses and sterilises the parasitic worm that causes the illness. Merck went on to study the treatment of elephantiasis. The research of Satoshi Ōmura, William Campbell, and their co-workers created a new class of drugs for the treatment of parasites.

In 1987, Merck decided to donate Ivermectin (Mectizan) to developing countries. Campbell was instrumental in that decision. With the World Health Organization they created an "unprecedented" drug donation program, with the intention of wiping out river blindness. As of 2001 an estimated 25 million people were being treated each year, in a total of 33 countries in sub-Saharan Africa, Latin America, and the Middle East. As of 2013, the Carter Center's International Task Force for Disease Eradication independently verified that the disease had been eradicated in Colombia, Ecuador, and Mexico.

The greatest challenge for science is to think globally, think simply and act accordingly. It would be disastrous to neglect the diseases of the developing world. One part of the world affects another part. We have a moral obligation to look after each other, but we're also naturally obligated to look after our own needs. It has to be both.

From 1990 to 2010, when he retired, Campbell was a research fellow at Drew University in Madison, N.J., where he supervised undergraduate research and taught courses in parasitology. He has written about the history of parasitology in Antarctic exploration, including the work of surgeon Edward L. Atkinson in Scott's ill-fated Terra Nova Expedition.

In 2002, Campbell was elected member of the United States National Academy of Sciences. In 2015, he and Satoshi Ōmura shared half of the 2015 Nobel Prize in Physiology or Medicine for their research on therapies against infections caused by roundworm parasites, using derivatives of avermectin. Campbell is the seventh Irish person to be awarded a Nobel Prize, including Ernest Walton who was awarded the Nobel Prize in Physics in 1951 and Samuel Beckett for Literature in 1968.

Personal life

William C. Campbell is married to Mary Mastin Campbell. He is a published poet and painter. His recreational activities include table tennis and kayaking.

Jai Ganesh · 2025-02-19 16:11:38

2167) Satoshi Ōmura

Gist:

Life

Satoshi Omura was born in Nirasaki, Yamanashi, Japan. He studied at the University of Yamanashi and at the Tokyo University of Science. He holds two doctorates: one in pharmaceutical science from the University of Tokyo from 1968 and one in chemistry from the Tokyo University of Science from 1970. He has then primarily worked at the Kitasato University, Minato, Tokyo, but is also affiliated with Wesleyan University, Middleton, Connecticut, USA.

Work

A number of serious infectious diseases are caused by parasites spread by insects. River blindness is caused by a tiny worm that can infect the cornea and cause blindness. Lymphatic filariasis, or elephantiasis, is also caused by a worm and produces chronic swelling. Satoshi Omura cultured bacteria, which produce substances that inhibit the growth of other microorganisms. In 1978 he succeeded in culturing a strain from which William Campbell purified a substance, avermectin, which in a chemically modified form, ivermectin, proved effective against river blindness and elephantiasis.

Summary

Ōmura Satoshi (born July 12, 1935, Yamanashi prefecture, Japan) is a Japanese microbiologist known for his discovery of natural products, particularly from soil bacteria. Of special importance was Ōmura’s discovery of the bacterium Streptomyces avermitilis, from which the anthelmintic compound avermectin was isolated. A derivative of avermectin known as ivermectin became a key drug used in the control of certain parasitic diseases in humans and other animals. For his contributions to the discovery of avermectin and ivermectin, Ōmura received the 2015 Nobel Prize for Physiology or Medicine (shared with Irish-born American parasitologist William Campbell and Chinese scientist Tu Youyou).

Ōmura earned a bachelor’s degree in 1958 from the University of Yamanashi and a master’s in 1963 from the Tokyo University of Science. In 1968 he completed a Ph.D. in pharmaceutical sciences at the University of Tokyo, and two years later, having returned to the Tokyo University of Science, he also earned a Ph.D. in chemistry. From 1963 to 1965, Ōmura worked as a research associate at the University of Yamanashi, and he afterward served under the same title at the Kitasato Institute, then one of the world’s leading microbiology research facilities. While completing his Ph.D. studies and carrying out research at the institute, he took a position as an associate professor at nearby Kitasato University. Between 1968 and 2007, when Ōmura was named professor emeritus at Kitasato University, he served variously as director and president of the Kitasato Institute as well as a professor and director of the university (the university became part of the institute in 2008). In 2013 he was given the title distinguished emeritus professor at Kitasato.

From the mid-1960s, Ōmura’s research centred on the discovery and isolation of naturally occurring bioactive chemical compounds from microorganisms, particularly from bacteria living in the soil. Ōmura developed novel techniques that facilitated the growth of soil bacteria in laboratory cultures and enabled the characterization of the substances they produced. Among his first major discoveries was the identification in the mid-1970s of cerulenin, an antibiotic produced by a species of fungus. Ōmura found that cerulenin worked by inhibiting the biosynthesis of fatty acids. The compound subsequently became an important research tool.

Also in the mid-1970s, Ōmura discovered and successfully cultured new strains of Streptomyces soil bacteria, including S. avermitilis. Ōmura sent a culture of S. avermitilis to researchers at Merck Research Laboratories in the United States. There, from broth collected from cultures of the organism, parasitologist William Campbell and colleagues identified a new family of compounds known as avermectins. The Merck researchers subsequently modified the avermectin structure, thereby producing ivermectin, which was found to be active against the microfilariae (larvae) of certain threadlike nematodes. Ivermectin became one of the world’s most-important anthelmintic agents, being used to treat various microfilariae-associated parasitic diseases in humans and other animals. In humans, the drug proved to be especially valuable for the prevention of river blindness and lymphatic filariasis (elephantiasis), which were major causes of debilitating disease in the tropics.

Ōmura discovered a number of other important microbial products, including many that became widely used as agrochemicals or as reagents in laboratory research and some that were found to possess antitumour activity. Much of Ōmura’s later research focused on elucidating the genetic mechanisms underlying the production of chemical substances by microorganisms.

Ōmura was an author on more than 1,100 scientific papers and was a member of multiple societies, including the Royal Society of Chemistry, to which he was elected an honorary member in 2005. In addition to the Nobel Prize, he was the recipient of many other honours and awards, including the Canada Gairdner Global Health Award (2014).

Details

Satoshi Ōmura (Ōmura Satoshi, born 12 July 1935) is a Japanese biochemist. He is known for the discovery and development of hundreds of pharmaceuticals originally occurring in microorganisms. In 2015, he was awarded the Nobel Prize in Physiology or Medicine jointly with William C. Campbell for their role in the discovery of avermectins and ivermectin, the world's first endectocide and a safe and highly effective microfilaricide. It is believed that the large molecular size of ivermectin prevents it from crossing the blood/aqueous humour barrier, and renders the drug an important treatment of helminthically-derived blindness.

Early life and education

Satoshi Ōmura was born in Nirasaki, Yamanashi Japan in 1935, the second son of Ōmura family. After graduating from the University of Yamanashi in 1958, he was appointed to science teacher at Tokyo Metropolitan Sumida Tech High School. In 1960, he became an auditor of Koji Nakanishi’s course at Tokyo University of Education, one year later, he enrolled in the Tokyo University of Science (TUS) and studied sciences. Ōmura received his M.S. degree from TUS and his Ph.D. in Pharmaceutical Sciences from the University of Tokyo (1968, a Dissertation PhD) and a Ph.D. in Chemistry at TUS (1970).

Career

Since 1965 Ōmura served at Kitasato Institute system. From 1970 to 1990, he also became a part-time lecturer at Tokyo University of Science.

In 1971 while he was a visiting professor at Wesleyan University, he consulted the chairman of the American Chemical Society, Max Tishler, at an international conference. Together they successfully acquired research expenses from Merck & Co. Ōmura was considering continuing his research in the United States, but ultimately he decided to return to Japan.

In 1973, he became a director of the antibiotic laboratory at Kitasato University, and he also started collaborative research with Merck & Co.

In 1975, he became professor of Kitasato University School of Pharmacy. Meanwhile, the Ōmura laboratory raised many researchers and produced 31 university professors and 120 doctors.

At present date, Ōmura is professor emeritus at Kitasato University and Max Tishler Professor of Chemistry at Wesleyan University.

Research

Satoshi Ōmura is known for the discovery and development of various pharmaceuticals originally occurring in microorganisms. He was awarded the 2015 Nobel Prize in Physiology or Medicine jointly with William C. Campbell for discoveries concerning a novel therapy against infections caused by roundworm parasites. More precisely, his research group isolated a strain of Streptomyces avermitilis that produce the anti-parasitical compound avermectin. Campbell later acquired these bacteria and developed the derived drug ivermectin that was first commercialised for veterinary use in 1981 later put to human use against Onchocerciasis in 1987–88 with the name Mectizan, and is today used against river blindness, lymphatic filariasis, scabies, other parasitic infections.

Since the 1970s, Ōmura has discovered more than 480 new compounds, of which 25 kinds of drugs and reagents are in use. Examples include andrastin, herbimycin, neoxaline as well as:

* a specific inhibitor of protein kinase named staurosporine;
* a proteasome inhibitor named lactacystin;
* a fatty acid biosynthesis inhibitor named cerulenin;

Furthermore, compounds having a unique structure and biological activity discovered by Omura are drawing attention in drug discovery research, and new anticancer drugs and the like have been created.

Social role

Ōmura served as deputy director and director at the Kitasato Institute. He was devoted to rebuild the laboratory and promoting the establishment of the medical center that is now Kitasato University Medical Center. Meanwhile, he established a path to rebuilding of the corporate school juridical person, which has integrated with the School corporation Kitasato Gakuen. He succeeded in establishing a new "School corporation Kitasato Institute". In addition, he served as president of the School corporation Joshibi University of Art and Design twice, and served as the honorary school chief of the School corporation Kaichi Gakuen. In 2007, he established the Nirasaki Omura Art Museum on his collection.

Jai Ganesh · Yesterday 15:46:49

2168) Tu Youyou

Gist:

Life

Tu Youyou was born and raised in Ningbo, Zhejiang, China. She studied at the Peking University in Beijing. Since 1965 she has worked at the China Academy of Traditional Chinese Medicine, where she is now Chief Scientist. Tu Youyou is married and has two daughters.

Work

A number of serious infectious diseases are caused by parasites spread by insects. Malaria is caused by a single-cell parasite that causes severe fever. In the 1970s, after studies of traditional herbal medicines, Tu Youyou focused on sweet wormwood and managed to extract a substance, artemisinin, which inhibits the malaria parasite. Drugs based on artemisinin have led to the survival and improved health of millions of people.

Summary

Tu Youyou (born December 30, 1930, Ningbo, Zhejiang province, China) is a Chinese scientist and phytochemist known for her isolation and study of the antimalarial substance qinghaosu, later known as artemisinin, one of the world’s most effective malaria-fighting drugs. For her discoveries, Tu received the 2015 Nobel Prize for Physiology or Medicine (shared with Irish-born American parasitologist William Campbell and Japanese microbiologist Ōmura Satoshi).

Tu studied at the department of pharmaceutics of Beijing Medical College. After earning a degree there in 1955, she was chosen to join the Institute of Materia Medica at the Academy of Traditional Chinese Medicine (later the China Academy of Chinese Medical Sciences). From 1959 to 1962, she participated in a full-time training course in the use of traditional Chinese medicine that was geared toward researchers with knowledge of Western medicine. The course provided a foundation for her later application of traditional Chinese medical knowledge to modern drug discovery.

In 1969, during the Vietnam War (1954–75), Tu was appointed to lead Project 523, a covert effort to discover a treatment for malaria. The project was initiated by the Chinese government at the urging of allies in North Vietnam, where malaria had claimed the lives of numerous soldiers. Tu and her team of researchers began by identifying plants with supposed activity against malaria on the basis of information from folk medicine and remedies described in ancient Chinese medical texts. Her team identified some 640 plants and more than 2,000 remedies with potential antimalarial activity and subsequently tested 380 extracts from about 200 of the plant species for their ability to rid malaria-causing Plasmodium parasites from the blood of infected mice. An extract obtained from the sweet wormwood plant (qinghao), Artemisia annua, showed particular promise. In 1971, after refining the extraction process, Tu and colleagues successfully isolated a nontoxic extract from sweet wormwood that effectively eliminated Plasmodium parasites from mice and monkeys. Clinical studies were soon thereafter carried out in malaria patients, in whom sweet wormwood extracts were found to quickly lower fever and reduce parasite levels in the blood. In 1972 Tu and colleagues isolated the active compound in the extracts, which they named qinghaosu, or artemisinin.

Although Tu had relied on information from ancient texts, the works said little about the plant known as qinghao, and many of her team’s early attempts to reproduce their initial findings on the plant’s antimalarial activity failed. Eventually, however, Tu discovered that the leaves of sweet wormwood contain artemisinin and that the compound is extracted optimally at relatively low temperatures. Tu initially was prevented from publishing her team’s findings, because of restrictions on the publication of scientific information that were in place in China at the time. The work finally reached international audiences, to wide acclaim, in the early 1980s. In the early 2000s, the World Health Organization recommended the use of artemisinin-based combination drug therapies as first-line treatment for malaria.

Tu continued to investigate artemisinin and developed a second antimalarial compound, dihydroartemisinin, which is a bioactive artemisinin metabolite. In 2011 she received the Lasker-DeBakey Clinical Medical Research Award for her contributions to the discovery of artemisinin.

Details

Tu Youyou (born 30 December 1930) is a Nobel Prize-winning Chinese malariologist and pharmaceutical chemist. She discovered artemisinin (also known as qīnghāosù) and dihydroartemisinin, used to treat malaria, a breakthrough in twentieth-century tropical medicine, saving millions of lives in South China, Southeast Asia, Africa, and South America.

For her work, Tu received the 2011 Lasker Award in clinical medicine and the 2015 Nobel Prize in Physiology or Medicine jointly with William C. Campbell and Satoshi Ōmura. Tu is the first Chinese Nobel laureate in Physiology or Medicine and the first female citizen of the People's Republic of China to receive a Nobel Prize in any category. She is also the first Chinese person to receive the Lasker Award. Tu was born, educated and carried out her research exclusively in China.

Tu was bestowed the Medal of the Republic, the highest honorary medal of the People's Republic of China, in September 2019.

Early life

Tu was born in Ningbo, Zhejiang, China, on 30 December 1930.

My [first] name, Youyou, was given by my father, who adapted it from the sentence translated as "Deer bleat youyou while eating wild Hao" in the Chinese Book of Odes. How this links my whole life with qinghao will probably remain an interesting coincidence forever.

— Tu Youyou, when interviewed in 2011 after being awarded the 2011 Lasker-DeBakey Clinical Medical Research Award

She attended Xiaoshi Middle School for junior high school and the first year of high school, before transferring to Ningbo Middle School in 1948. A tuberculosis infection interrupted her high-school education, but inspired her to go into medical research. From 1951 to 1955, she attended Peking University Medical School / Beijing Medical College. In 1955, Youyou Tu graduated from Beijing Medical University School of Pharmacy and continued her research on Chinese herbal medicine in the China Academy of Chinese Medical Sciences. Tu studied at the Department of Pharmaceutical Sciences, and graduated in 1955. Later Tu was trained for two and a half years in traditional Chinese medicine.

After graduation, Tu worked at the Academy of Traditional Chinese Medicine (now the China Academy of Traditional Chinese Medical Sciences) in Beijing.

Research career

Tu carried on her work in the 1960s and 70s, including during China's Cultural Revolution.

Schistosomiasis

During her early years in research, Tu studied Lobelia chinensis, a traditional Chinese medicine believed to be useful for treating schistosomiasis, caused by trematodes which infect the urinary tract or the intestines, which was widespread in the first half of the 20th century in South China.

Malaria

In 1967, during the Vietnam War, President Ho Chi Minh of North Vietnam asked Chinese Premier Zhou Enlai for help in developing a malaria treatment for his soldiers trooping down the Ho Chi Minh trail, where a majority came down with a form of malaria which is resistant to chloroquine. Because malaria was also a major cause of death in China's southern provinces, especially Guangdong and Guangxi, Zhou Enlai convinced Mao Zedong to set up a secret drug discovery project named Project 523 after its starting date, 23 May 1967.

In early 1969, Tu was appointed head of the Project 523 research group at her institute. Tu was initially sent to Hainan, where she studied patients who had been infected with the disease.

Scientists worldwide had screened over 240,000 compounds without success. In 1969, Tu, then 39 years old, had an idea of screening Chinese herbs. She first investigated the Chinese medical classics in history, visiting practitioners of traditional Chinese medicine all over the country on her own. She gathered her findings in a notebook called A Collection of Single Practical Prescriptions for Anti-Malaria. Her notebook summarized 640 prescriptions. By 1971, her team had screened over 2,000 traditional Chinese recipes and made 380 herbal extracts, from some 200 herbs, which were tested on mice.

One compound was effective, sweet wormwood (Artemisia annua), which was used for "intermittent fevers," a hallmark of malaria. As Tu also presented at the project seminar, its preparation was described in a recipe from a 1,600-year-old traditional Chinese herbal medicine text titled Emergency Prescriptions Kept Up One's Sleeve. At first, it was ineffective because they extracted it with traditional boiling water. Tu discovered that a low-temperature extraction process could be used to isolate an effective antimalarial substance from the plant; Tu says she was influenced by the source, written in 340 by Ge Hong, which states that this herb should be steeped in cold water. This book instructed the reader to immerse a handful of qinghao in water, wring out the juice, and drink it all. Since hot water damages the active ingredient in the plant, she proposed a method using low temperature ether to extract the effective compound instead. Animal tests showed it was completely effective in mice and monkeys.

In 1972, she and her colleagues obtained the pure substance and named it qinghaosu , or artemisinin in English. This substance has now saved millions of lives, especially in the developing world. Tu also studied the chemical structure and pharmacology of artemisinin. Tu's group first determined the chemical structure of artemisinin. In 1973, Tu was attempting to confirm the carbonyl group in the artemisinin molecule when she accidentally synthesized dihydroartemisinin.

Tu voluntered to be the first human test subject. "As head of this research group, I had the responsibility," she said. It was safe, so she conducted successful clinical trials with human patients. Her work was published anonymously in 1977. In 1981, she presented the findings related to artemisinin at a meeting with the World Health Organization.

For her work on malaria, she was awarded the Nobel Prize in Medicine on 5 October 2015.

Later career

Tu Youyou was promoted to Researcher (the highest researcher rank in mainland China equivalent to the academic rank of a full professor) in 1980, shortly after the beginning of the Chinese economic reform in 1978. In 2001, she was promoted to academic advisor for doctoral candidates. As of 2023, she is the chief scientist of the China Academy of Chinese Medical Sciences.

As of 2007, her office is in an old apartment building in Dongcheng District, Beijing.

Before 2011, Tu Youyou had been obscure for decades, and is described as "almost completely forgotten by people".

Tu is regarded as the "Three-Without Scientist" – no postgraduate degree (there was no postgraduate education then in China), no study or research experience abroad, and not a member of either of the Chinese national academies, the Chinese Academy of Sciences and Chinese Academy of Engineering. Tu is now regarded as a representative figure of the first generation of Chinese medical workers since the establishment of the People's Republic of China in 1949.

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