http://macromoleculas.unq.edu.ar
bmacro05@yahoo.com
Pasword: lactamasa
Friedrich August
Kekule (1829-1896)
El concepto de macromolécula surgió naturalmente a
principios del siglo XIX
Eduard Pfluger
1875 Teoría de la respiración intracelular
Biuret
Análisis elemental: en 300 g de hemoglobina hay 1 g de hierro
Fórmula mínima: 1 mol de hemoglobina por mol de hierro
(16000 g de hemoglobina por 52 g de hierro)
Peso Molecular: n16000
Emil Fischer (premio Nobel 1902)
Las proteínas están constituídas por péptidos de hasta 30 residuos
Existen unos treinta aminoácidos naturales, por lo tanto los
isómeros posibles son 30!=31032
En realidad el cálculo es 3030=31044
La teoría de los biocoloides
•Alfred Werner postula la existencia de dos tipos de valencia
química
•Aparecen los primeros datos de rayos X aplicados a fibras y
las celdas unitarias son pequeñas
•Aparece la biocoloidología, bautizada como “the dark age”
por Florkin
El axioma de la biocoloidología fue:
El estado coloidal es un nuevo estado de la
materia al cual no se aplican las leyes
convencionales de la química
El debate sobre las macromoléculas
Herman Staudinger (1881-1965)
Premio Nobel 1953
HE R M A N N S T A U D I N G E R
Macromolecular chemistry
Nobel Lecture, December 11, 1953
In many instances a polymeric compound can be transformed
into derivatives of a different type without any change in the degree
of polymerization of the compound in exactly the same way as small
molecules can be transformed. A polymer compound can hence be
transformed into polymer analogous derivatives, the transformation
proving that all the basic molecules contained in the colloid particles
of these polymeric compounds are linked together by chief valences,
in other words the colloid particles are macromolecules. This proof
becomes especially clear because out of a series of polymer
homologues various ones can be transformed into polymer
analogous derivatives.
Theodor Svedberg (1884-1971)
Premio Nobel 1926
Complejidad estructural y
estrategia de síntesis
Síntesis no modular
la estructura está acoplada
directamente a la síntesis
Taxol
Síntesis modular
síntesis disociada del plegado
glutamato sintasa
1 cadena, 1500 residuos,
20000 átomos
proteína A
1 cadena, 60
residuos,  900
átomos
vitamina B12 (200
átomos)
Lawrence Bragg
William Bragg
Dorothy Crowfoot (1910-1994)
Premio Nobel 1964
Cristalografía en la UNQ (LEPP)
IA-2
2qt7.pdb
armadillo ACBP (2fdq.pdb)
ylSCP2
pChP
Atsbury under attack
Linus Pauling
(1901-1994)
Premio Nobel
Pauling had been practically apolitical until World War II, but the war changed his life profoundly, and he became
a peace activist. During the beginning of the Manhattan Project, Robert Oppenheimer invited him to be in charge
of the Chemistry division of the project, but he declined saying that he was a pacifist. In 1946 he joined the
Emergency Committee of Atomic Scientists, chaired by Albert Einstein, whose mission was to warn the public of
the dangers associated with the development of nuclear weapons. His political activism prompted the U.S. State
Department to deny him a passport in 1952, when he was invited to speak at a scientific conference in London.
His passport was restored in 1954, shortly before the ceremony in Stockholm where he received his first Nobel
Prize. Joining Einstein, Bertrand Russell and 8 other leading scientists and intellectuals he signed the RussellEinstein Manifesto in 1955.
In 1957, Pauling began a petition drive in cooperation with biologist Barry Commoner, who had studied
radioactive strontium-90 in the milk teeth of children across North America and concluded that above-ground
nuclear testing posed public health risks in the form of radioactive fallout. He also participated in a public debate
with the atomic physicist Edward Teller about the actual probability of fallout causing mutations. In 1958, Pauling
and his wife presented the United Nations with a petition signed by more than 11,000 scientists calling for an
end to nuclear-weapon testing. Public pressure subsequently led to a moratorium on above-ground nuclear
weapons testing, followed by the Partial Test Ban Treaty, signed in 1963 by John F. Kennedy and Nikita
Khrushchev. On the day that the treaty went into force, the Nobel Prize Committee awarded Pauling the Peace
Prize, describing him as "Linus Carl Pauling, who ever since 1946 has campaigned ceaselessly, not only against
nuclear weapons tests, not only against the spread of these armaments, not only against their very use, but
against all warfare as a means of solving international conflicts." Interestingly, the Caltech Chemistry
Department, wary of his political views, did not even formally congratulate him. However, the Biology
Department did throw him a small party, showing they were more appreciative and sympathetic toward his work
on radiation mutation.
Many of Pauling's critics, including scientists who appreciated the contributions that he had made in chemistry,
disagreed with his political positions and saw him as a naïve spokesman for Soviet communism. He was
ordered to appear before the Senate Internal Security Subcommittee, which termed him "the number one
scientific name in virtually every major activity of the Communist peace offensive in this country." An
extraordinary headline in Life magazine characterized his 1962 Nobel Prize as "A Weird Insult from Norway."
Pauling was awarded the International Lenin Peace Prize by the USSR in 1970.
It is further assumed that each nitrogen atoms forms a hydrogen bond with
an oxigen atom from another residue, with the nitrogen-oxygen distance
equal to 2.72A, and that the vector from the nitrogen atom to the hydrogen
bonded oxygen lies not more than 30 degrees from the N-H direction.
Solution of this problem shows that there are five and only five configuración
for the chain that satisfy the conditions other than that of direction of the
hydrogen bond relative to the N-H direction... 165, 120, 108 97.2, and 70
degrees for the rotational angle...
...the fourth and fifth are satisfactory, the angle between the N-vextor and N-O
vector being about 10 and 25 degrees for these two structures, respectively.
The fourth structure has 3.69 residues per turn, and the fifth 5.13.
Sir William Henry Bragg
(1862-1942)
Sir William Lawrence Bragg
(1890-1971)
Premio Nobel compartido 1915
DNA (Bell, Atsbury)