DYNAMICALLY CONTROLLED PROTEIN CRYSTAL GROWTH (DCPCG)
Research Area: Macromolecular Crystal Growth
Expedition(s): 3
Principal Investigator(s): ● Lawrence J. DeLucas, OD, PhD, University of Alabama at
Birmingham, Birmingham, Alabama
RESEARCH OBJECTIVES
Dynamically Controlled Protein Crystal Growth demonstrates significant advances in the ability
of researchers to control protein crystal growth processes. Previous research demonstrated
that macromolecular crystals grown in microgravity are frequently larger and more perfectly
formed than their Earth grown counterparts. Understanding the results obtained from the
crystals can lead to advances in manufacturing and biological processes.
EARTH BENEFITS
Proteins play a key role in the living world around us. They are the building blocks for humans
and other animals and they regulate the biochemical processes of plants. Knowledge of the
structure and design of proteins helps researchers design new drugs, combat disease, and
improve agricultural products, such as pesticides. Researchers are unlocking this knowledge by
studying protein crystals, their growth, and 3-D atomic structure. For the most part, drugs are
not so much discovered anymore, they are designed. Scientists can now target a specific
protein of a pathogen, be it bacterial or viral, to maximize a drug’s effectiveness while at the
same time minimizing possible side effects. This method, known as rational drug design, has
one major downside. The exact structure of the target protein must be determined, down to
the last molecule. To uncover this molecular structure, scientists use X-ray crystallography. A
crystal of the protein is bombarded with X-rays to produce a pattern, which, much like a
fingerprint, reveals the identity of the protein’s atomic structure. But to get an accurate
pattern, the crystal must be as free of imperfections as possible. Growing such crystals can be
extremely difficult, even impossible, on Earth because gravity causes the crystals to settle on
top of one another resulting in structural flaws.
The DCPCG system demonstrates significant advances in the ability of researchers to gain
control of the protein crystal growth process and provides tremendous opportunities for both
Glucose Isomerase crystals from Dynamically Controlled Protein Crystal Growth on International Space Station
Expedition 3. From left to right, fast evaporation rate, medium evaporation rate and slow evaporation rate. NASA
image.