Chemical & Engineering News Digital Edition - January 18, 2010

IN MAY 1961, “Big Science” was grabbing
headlines: On May 5, ground crews cheered
as Alan Shepard flew high enough to earn
the title “First American in Space.” Less
than three weeks later, on May 25, President
John F. Kennedy vowed that the U.S.
would put a man on the moon by the end of
the decade.
While these events were capturing the
nation’s imagination, a pair of scientists
quietly reached a breathtaking new frontier
right here on Earth. In the wee hours of
May 27, in Building 10 on the campus of the
National Institutes of Health, in Bethesda,
Md., researcher Marshall W. Nirenberg and
postdoc Heinrich Matthaei found the key
to deciphering the genetic code of virtually
all life on Earth—a biochemical Rosetta
Stone—in a humble test tube. That discovery
was recently honored by the American
Chemical Society as a National Historic
Chemical Landmark.
Nirenberg set out to prove the existence
of messenger RNA, which he did, but his
experiment yielded
much more. He
instructed Matthaei
to mix 20 samples
of synthetic mRNA
composed entirely
of uracil with a
specially prepared
cell-free extract of
Escherichia coli. For
each sample, Matthaei
introduced
one radiolabeled amino acid and 19 unlabeled
amino acids into the extract, varying
the “hot” amino acid in each tube.
The sample containing the radiolabeled
phenylalanine produced radioactive pro-
ACS NEWS
MARSHALL NIRENBERG’S
WORK HONORED
Research deciphering the GENETIC CODE is the
latest National Historic Chemical Landmark
TRANSLATION
Matthaei (left)
and Nirenberg
photographed
shortly after their
groundbreaking
experiment.
tein composed entirely of phenylalanine.
From these data, Nirenberg concluded
that the sequence UUU on mRNA was the
genetic code for phenylalanine.
This was the first step
in determining the genetic
instructions for all amino
acid synthesis and was also
the first demonstration that
mRNA, which had been postulated,
actually exists.
Within three years, Nirenberg
and his colleagues
had identified the RNA
codons of all 20 standard
amino acids that make up
proteins. For this work, Nirenberg was one
of three winners of the 1968 Nobel Prize in
Physiology or Medicine.
Many of Nirenberg’s former colleagues
and students were on hand as Nirenberg’s
work became ACS’s 64th National Historic
Chemical Landmark. Thomas H. Lane,
then-ACS president, presented a bronze
plaque describing
the groundbreaking
experiment to
Michael Gottesman,
NIH’s deputy
director for intramural
research, at
the close of a daylong
symposium
held in Building 10.
The symposium
was a tribute to
Nir enberg’s work
and was attended
by about 400 people,
primarily NIH
scientists. Titled
“Genes to Proteins:
Decoding Genetic
Information,”
the symposium
featured presentations of the classical
work and cutting-edge research and were
punctuated by personal reminiscences.
The symposium and landmark ceremony,
which together lasted more than five
WWW.CEN-ONLINE.ORG 28 JANUARY 18, 2010
NIH
hours, are available in their entirety to view
or download at videocast.nih.gov/launch.
asp?15434.
Videotaped remarks by NIH Director
Francis S. Collins were shown during
the symposium and sum up the impact of
Nirenberg’s work. “It is fair to say that Dr.
Nirenberg’s discoveries contributed to our
completing the human genome, mapping
human genetic variation, and studying the
correlations between variation and disease,”
said Collins, who is also the former
director of the National Human Genome
Research Institute.
“One day,
when medicine
is able to marshal
the power of
this knowledge
to personalize
medicine for
every individual,
the full promise
of Nirenberg’s
work will be realized,” he said.
LANDMARK Gottesman
(left) and Nirenberg
flank the plaque
designating the
deciphering of the
genetic code as a
National Historic
Chemical Landmark at
a National Institutes of
Health ceremony.
Nirenberg, 82, has spent his entire career
at NIH and is the longtime chief of its
National Heart, Lung & Blood Institute’s
Laboratory of Biochemical Genetics. He
came to NIH in 1957 as a postdoc working
on sugar transport, enzyme purification,
and glycogen metabolism. After being
hired as an independent researcher in
1959, he made an abrupt change in his research
focus that his then-colleague Bruce
N. Ames deemed “suicidal.” Nirenberg
made the move because he wanted to find
out whether DNA or RNA directed protein
synthesis. Although Nirenberg admitted
it was a risky thing for a new researcher
to do, he says Ames’s opinion “was a little
extreme.”
The Chemical Society of Washington
(the ACS Washington, D.C., local section)
sponsored the proposal for the landmark
status nearly three years ago. NIH Scientist
Emeritus Edwin D. (Ted) Becker, who
NIH