Microbiology and Immunology

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Woodward, Robert B. WORLD OF MICROBIOLOGY AND IMMUNOLOGY

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Wong-Staal moved to Bethesda, Maryland, where she worked
at the National Cancer Institute (NCI) with AIDS pioneer
Robert Gallo, studying retroviruses, the mysterious family of
viruses to which HIV belongs. Searching for a cause for the
newly discovered AIDS epidemic, Gallo, Wong-Staal, and
other NCI colleagues identified HIV in 1983, simultaneously
with a French researcher. In 1985, Wong-Stall was responsible
for the first cloningof HIV. Her efforts also led to the first
genetic mappingof the virus, allowing eventual development
of tests that screen patients and donated blood for HIV.
In 1990, the Institute for Scientific Information declared
Wong-Staal as the top woman scientist of the previous decade.
That same year, Wong-Staal returned to the University of
California at San Diego to continue her AIDS research. Four
years later, the university created a new Center for AIDS
Research; Wong-Staal became its chairman. There, she works
to find both vaccines against HIV and a cure for AIDS, using
the new technology of genetherapy.

See alsoAIDS, recent advances in research and treatment

WWoodward, Robert B.OODWARD, ROBERT B.(1917-1979)

American biochemist

Robert B. Woodward was arguably the greatest organic synthe-
sis chemist of the twentieth century. He accomplished the total
synthesis of several important natural products and pharmaceu-
ticals. Total synthesis means that the molecule of interest—no
matter how complex—is built directly from the smallest, most
common compounds and is not just a derivation of a related
larger molecule. In order to accomplish his work, Woodward
combined physical chemistry principles, including quantum
mechanics, with traditional reaction methods to design elaborate
synthetic schemes. With Nobel Laureate Roald Hoffmann, he
designed a set of rules for predicting reaction outcomes based on
stereochemistry, the study of the spatial arrangements of mole-
cules. Woodward won the Nobel Prize in chemistry in 1965.
Robert Burns Woodward was born in Boston on April
10, 1917, to Arthur and Margaret (Burns) Woodward. His
father died when he was very young. Woodward obtained his
first chemistry set while still a child and taught himself most
of the basic principles of the science by doing experiments at
home. By the time he graduated at the age of 16 from Quincy
High School in Quincy, Massachusetts, in 1933, his knowl-
edge of chemistry exceeded that of many of his instructors. He
entered the Massachusetts Institute of Technology (MIT) the
same year but nearly failed a few months later, apparently
impatient with the rules and required courses.
The MIT chemistry faculty, however, recognized
Woodward’s unusual talent and rescued him. They obtained
funding and a laboratory for his work and allowed him com-
plete freedom to design his own curriculum, which he made
far more rigorous than the required one. Woodward obtained
his doctorate degree from MIT only four years later, at the age
of 20, and then joined the faculty of Harvard University after
a year of postdoctoral work there.

Woodward spent virtually all of his career at Harvard
but also did a significant amount of consulting work with var-
ious corporations and institutes around the world. As is true in
most modern scientific endeavors, Woodward’s working style
was characterized by collaboration with many other
researchers. He also insisted on utilizing the most up-to-date
instrumentation, theories.
The design of a synthesis, the crux of Woodward’s
work, involves much more than a simple list of chemicals or
procedures. Biochemical molecules exhibit not only a particu-
lar bonding pattern of atoms, but also a certain arrangement of
those atoms in space. The study of the spatial arrangements of
molecules is called stereochemistry, and the individual config-
urations of a molecule are called its stereoisomers. Sometimes
the same molecule may have many different stereoisomers;
only one of those, however, will be biologically relevant.
Consequently, a synthesis scheme must consider the basic
reaction conditions that will bond two atoms together as well
as determine how to ensure that the reaction orients the atoms
properly to obtain the correct stereoisomer.
Physical chemists postulate that certain areas around an
atom or molecule are more likely to contain electrons than other
areas. These areas of probability, called orbitals, are described
mathematically but are usually visualized as having specific
shapes and orientations relative to the rest of the atom or mole-
cule. Chemists visualize bonding as an overlap of two partially
full orbitals to make one completely full molecular orbital with
two electrons. Woodward and Roald Hoffmann of Cornell
University established the Woodward-Hoffmann rules based on
quantum mechanics, which explain whether a particular overlap
is likely or even possible for the orbitals of two reacting species.
By carefully choosing the shape of the reactant species and
reaction conditions, the chemist can make certain that the atoms
are oriented to obtain exactly the correct stereochemical config-
uration. In 1970, Woodward and Hoffmann published their clas-
sic work on the subject, The Conservation of Orbital Symmetry;
Woodward by that time had demonstrated repeatedly by his
own startling successes at synthesis that the rules worked.
Woodward and his colleagues synthesized a lengthy list
of difficult molecules over the years. In 1944 their research,
motivated by wartime shortages of the material and funded by
the Polaroid Corporation, prompted Woodward—only 27
years old at the time—and William E. Doering to announce
the first total synthesis of quinine, important in the treatment
of malaria. Chemists had been trying unsuccessfully to syn-
thesize quinine for more than a century.
In 1947, Woodward and C. H. Schramm, another
organic chemist, reported that they had created an artificial
protein by bonding amino acids into a long chain molecule,
knowledge that proved useful to both researchers and workers
in the plastics industry. In 1951, Woodward and his colleagues
(funded partly by Merck and the Monsanto Corporation)
announced the first total synthesis of cholesterol and corti-
sone, both biochemical steroids. Cortisone had only recently
been identified as an effective drug in the treatment of
rheumatoid arthritis, so its synthesis was of great importance.
Woodward’s other accomplishments in synthesis
include strychnine (1954), a poison isolated from Strychnos

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