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BARCELONA

SPANISH SCIENTISTS

Santiago Ramón y Cajal

Severo Ochoa

Joan Oró

Santiago Ramón y Cajal was born in Petilla de Aragón on 1st May, 1852.

He studied medicine at the university of Zaragoza, and he also went to the university of Barcelona.

He was a Spanish pathologist, histologist, neuroscientist and he won a Nobel Award.

Santiago went to the compulsory (at that time) military service.

He focused on the pathology of inflammation, the microbiology of cholera, and the structure of Epithelial cells and tissues at the University of Zaragoza.

When he went to Barcelona he made extensive studies of neural material of many species and most major regions of the brain.

Ramón y Cajal made several contributions to neuroanatomy.

He discovered the axonal growth cone, and he demonstrated that the relationship between nerve cells was not continuous but contiguous. This provided a lot of evidence for the Neuron Doctrine.

Cajal proved the histological and functional individuality of nerve cells. He also proved how the nervous stream flowed through the cell and how they communicated with each other: by contiguity, and not by continuity. This theory put an end to the reticularisttheory that prevailed in the medical world. Likewise, he discovered the synapses, a form of neuron connection.

He discovered a new type of cell to be named after him: the interstitial cell of Cajal. This cell is found interleaved among neurons embedded within the smooth muscles lining the gut, serving as the generator and pacemaker of the slow waves of contraction that move material along the gastrointestinal tract, vitally mediating neurotransmission from motor nerves to smooth muscle cells.

-The neurons are used to communicate information to the brain and among them, they also create paths with each other, and because of that we can remember a lot of things. If he hadn’t discovered them, we wouldn’t know about some illnesses like: Alzheimer, Parkinson and ELA.

-Cajal’s interstitial cells: These cells are used to generate an activity or system like a “pacemaker” for the intestinal muscle and they are also used to serve synapses or to make a bridge between the terminations of the autonomic nervous system and the smooth muscle cells of the intestine.

Severo Ochoa was born in Luarca (Asturias), Spain. His father was Severo Manuel Ochoa, a lawyer and a businessman, and his mother was Carmen de Albornoz. Ochoa was the nephew of Alvaro de Albornoz (President of the Second Spanish Republic that was exiled, 1947–1951), and a cousin of the poet and literary poet and critic Aurora de Albornoz. His father died when Ochoa was seven, and he and his mother moved to Málaga, where he attended elementary school through high school. His interest in biology was stimulated by the publications of the Spanish neurologist and Nobel laureate Santiago Ramón y Cajal. In 1923, he went to the University of Madrid Medical School, where he hoped to work with Cajal, but Cajal retired. He studied with father Pedro Arrupe, and Juan Negrín was his teacher.

Ochoa was the scientist who managed to close the Krebs cycle. The Krebs cycle is a central metabolic pathway in living organisms that carry out cellular respiration.

The Krebs cycle is not only an energy function, but also provides the precursors for the synthesis of various amino acids .Ochoa enzymes are produced during the Krebs cycle itself. Its importance in the process lies in the oxidation reaction of these enzymes , which depend on the energy charge of the cell, it produces compounds that are used to direct the processes of oxidative phosphorylation, leading to Ochoa to develop his major research on the genetic code.

He decided to continue his investigations about the oxidative phosphorylation.

So he discovered a new enzyme, the enzyme is called ‘polynucleotide phosphorylase’, it can synthesize RNA in a test tube.

The oxidative phosphorylation consists in a metabolic way which uses the left energy of the process of the oxidation of the proteins in the nutrients to, using the fatty acids and glucose, to produce ATP(energy), H20 (water) and CO2(carbon dioxide).

The synthesizing of the RNA, out of the cell consists in an enzyme isolated of the microorganism Azotobacter Vinelandii catalyzes the synthesis of highly polymerized orthophosphate releases polynucleotides.

The discovery of that enzyme (polynucleotide phosphorylase) caused the preparation of the synthetic polynucleotide of a different composition, with which Ochoa finally could finish his investigation about the RNA and this investigation made him win the Nobel Prize of Medicine in 1959.

The contribution of Severo Ochoa is concentrated in different works that developed the earlier findings and ideas that are related to the decoding of the genetic code, the intracellular protein biosynthesis and fundamental aspects of virus’ biology.

RNA RNA is the one that makes the protein

synthesis and is in charge of transporting the DNA to the ribosomes.

Therapy with RNA The use of RNA molecules in the

therapy of certain diseases surge as alternative for solving some problems of traditional gene therapy. The recent advances in understanding the biology of RNA, as the discovery of the process of RNA interference (RNAi), have allowed the investigation of the possibilities of RNA as a therapeutic molecule of certain genetic diseases.

Joan Oró i Florensa was born in Lleida on 26 October 1923, and died in Barcelona on 2nd September, 2004.

Since early childhood he was interested in the human’s role in the universe, and in 1947 he graduated from chemistry at the university of Barcelona.

In 1952 he moved to the United States, where he graduated from biochemistry at Houston University in 1955.

His doctoral thesis studied the metabolism of formic acid in animal tissue. He also made important studies on existing organic compounds in terrestrial sediments, meteorites and samples from the Moon.

From 1963 he worked in several research NASA space projects, as the Apollo project for the analysis of rocks and other material samples from the moon, and the Viking program for the development of an instrument for the molecular analysis of the atmosphere and the raw surface of Mars.

In 1980 he came back to Catalonia to collaborate in new energy development plans and study alternative energy sources.

One of his most important contributions was the prebiotic synthesis of the nucleobase adenine (a key component of nucleic acids) from hydrogen cyanide (HCN). He also showed that amino acids can be made from HCN plus ammonia in an aqueous solution. This was achieved between 1959–1962 and stands, together with the Miller-Urey experiment, as one of the fundamental results of pre-biotic chemistry. It opened up a research area eventually leading to the complete synthesis of other components of nucleic acids.

• Oró wrote in his book, The origin of life: “Some of the pre-biotic process are reproducible, and it’s been found that the aqueous or liquid medium is most suitable for development. So it is almost certain that life sprang up in what has been called primary sea or primitive ocean. “• Joan Oró was one of the pioneers of the theory of panspermia as a cause of the origin of life on our planet. The theory of panspermia said that the organic matter that gave rise to life could reach Earth in comets that hit on the primitive Earth. In his research he developed a scheme that goes from the first thermonuclear transformations to the beginning of life in our planet.

Studying the origin of life, Joan Oró showed that hydrogen cyanide (HCN)* was a molecule that could easily provide laboratory nitrogenous bases of DNA, like adenine and guanine.

In 1961 he got the artificial synthesis of adenine, from a mixture of hydrogen cyanide and ammonia added to water. Later, he added to his basic mixture formaldehyde and found the ribose and deoxyribose, also components of nucleic acid sugars. In addition to these compounds, he also obtained a mixture of amino acids and polypeptides of great biological interest.

* Hydrogen cyanide (HCN) is a molecule consisting of three atoms that was found in the interstellar medium and one that provided abundant components on Miller's experiment.

Hydrogen cyanide (HCN)

Ammonia (NH3)Formaldehyde (CH2O)

He was also the first scientist pointing towards comets as key carriers of organic molecules to our early biosphere. This conjecture (formulated in 1961) is largely accepted today. Although such idea had been around for a long time, it was only when both space exploration and pre-biotic chemistry were fully developed that extensive evidence was in place.

Comets are known to be rich in carbon and water, bearing along precursor molecules based on carbon chemistry such as amino acids. In this context, in 1971 Oró and co-workers published a paper revealing the high abundance of Amino-acids, aliphatic and aromatic hydrocarbons in the Murchison meteorite.

Murchison meteorite

If Joan Oró had never made these two theories, we wouldn’t have known about Adenine and its use in DNA and RNA, and thanks to Joan Oró we can make new theories about the origin of life and we have more ideas about how life was created.