student creates new procedure during summer internship at NIST
February 24, 2003
the early morning stillness, the empty lab echoed with Melanie Bernard's
footsteps as she approached the experiment she had set up the night
before. The shells of her choker necklace seemed tighter than usual.
If crystals had formed in the tiny wells in the seven plates that
she had filled, the Vanderbilt senior would have created a special
test, called a screen, that would eliminate the thousands of experiments
normally required to determine the molecular structure of members
of a specific hemoglobin family, the special proteins that transport
oxygen through the blood and give it its red color.
of Melanie Bernard
from her seven test subjects - a horse, a rabbit, a baboon, a human,
a cow, a pig - were arranged on the counter in front of her. Bernard
looked for crystals or "hits" in each drop of red liquid.
Leaning over the plates she scanned the tiny wells and let her shoulders
relax. Perfect crystals had formed in most of the wells, and she
knew that more would form over the next two weeks.
is majoring in Biomedical/Electrical Engineering at Vanderbilt,
created the hemoglobin screen during an internship last summer at
the National Institute of Standards and Technology (NIST). Her screen
is important because it is the first screen developed for a targeted
family of proteins, and it will be used by NIST to accelerate the
process of determining crystallization patterns for that protein
family. The screen is only one step in the process of determining
protein structure, but it reduces the thousands of crystallization
experiments to a couple dozen, saving resources, time and money
according to her advisor at NIST.
under the direction of Gary Gilliland, Biotechnology Division Chief
at NIST and "a big cheese" in the world of protein crystallography,
according to Bernard.
of Melanie Bernard
the functions of proteins is especially useful now that scientists
have mapped the human genome and the genome of an increasing number
of other organisms. NIST, a global leader in setting standards of
measurement, is responsible for contributing the 30,000 to 40,000
protein structures encoded by the human genome to its Protein Data
that her daily job at the NIST lab was to conduct experiments to
determine what conditions make different proteins crystallize. Once
scientists have a pure protein crystal, they can use a powerful
technique called X-ray crystallography to determine its structure.
When an X-ray beam passes through a crystal, it produces a complex
pattern of light and dark spots on a detection screen. By analyzing
the location and intensity of these dots, experts can reconstruct
the type and position of the individual atoms that the crystal contains.
Once a protein structure has been completely determined, this information
is deposited in the Protein Data Bank.
importance of developing the hemoglobin screen, Bernard's reaction
was one of relief rather than excitement - relief that all of her
work hadn't been for nothing, she explained. Instead, it was her
adviser who was excited. He was able to use Bernard's work in his
lecture at the 19th meeting of the International Union of Crystallography
in Geneva Switzerland.
described in the talk was Melanie's work that involved reviewing
all of the crystallization data concerning hemoglobins and related
proteins. Melanie's screen was tested against a battery of different
hemoglobins and proved quite successful," Gilliland said. He
also noted that Bernard will receive recognition for her work in
a paper that he will be submitting to the scientific journal Acta
one of 102 students nationwide chosen to intern last summer at NIST,
a federal agency located in Gaithersburg, Maryland. Bernard wanted
to explore her career options with a summer internship.
of Melanie Bernard
photo of NIST interns
wondering if life in a cubicle was how it was going to be,"
Bernard reflected upon her desk job the previous summer. In search
of hands-on laboratory experience, Bernard applied to and was accepted
at NIST to help develop screens for various proteins.
project at NIST, however, was disappointing. "They started
me out doing data entry because I had some computer programming
experience and that wasn't what I had expected to do," she
said. "But I asked my advisor, Dr. Gilliland, if there was
something else I could do and he brought me over to his auxiliary
lab at the University of Maryland."
lab in the Chemical Science and Technology department of NIST and
at the University of Maryland specializes in the crystallization
of biological macromolecules. The department has determined the
three-dimensional crystal structures of thousands of molecules and
has created a crystallization database to house and consolidate
that information. Melanie's screen is based on information from
this database, a recipe book for thousands of crystal structures.
that understanding a protein's crystallization structure is especially
useful for scientists when designing drugs for medicinal purposes.
"HIV protease inhibitors for the treatment of AIDS are a good
example of drugs that were developed using the structure-based drug
design approach," said Gilliland. "Knowledge of the structure
and function of the complete set of proteins is also critical to
understanding the basic processes of life," he said.
of Melanie Bernard
included a stipend and housing in an apartment complex in Gaithersburg
with the other students who were chosen for the internship. The
housing situation made her experience quite social, according to
Bernard, who said she spent a lot of time with the other students.
"It was a pretty sweet deal," Bernard said, referring
to the swimming pool and maid service in her apartment complex.
9 A.M. - 5 P.M. every day in various labs at NIST. They also attended
seminars each Friday to learn about the agency's current research
projects. One seminar focused on NIST's development of autonomous
robots that were used to search the World Trade Center after 9/11,
her work at NIST and discovered the rewarding aspects of her field
of study. "Each day is like a surprise to see if your experiment
worked," she said. Bernard felt most satisfied with her internship
when her advisor commented that he was impressed with her results
and that he was glad she had complained about her initial data-entry
is a senior majoring in communications studies at Vanderbilt.