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Glossary
Bioreactor:
See rotating-wall vessel.
Biotechnology Facility:
A specialized facility scheduled to be installed on the International Space Station in 2005. Current plans call for it to support both cell science and protein crystal growth research.
Biotechnology Temperature Controller:
A combination refrigerator/incubator with the capability to preserve and incubate multiple cell cultures simultaneously.
Cell Culture Unit:
A modular cassette-style bioreactor that can accommodate multiple cell culture chambers. It is under development at MIT for the NASA Life Sciences Division.
Crystal Preparation Prime Item:
Unit containing robotic instrumentation that harvests, mounts, and freezes protein crystal samples. Part of the X-ray Crystallography Facility for ISS.
Discipline Working Group:
Advisory panel for NASA on the scope of research announcements, peer-review practices, and future programmatic directions.
EXPRESS racks:
Basic support structures to house experimental equipment on the ISS and to transport instruments and samples on the space shuttle. EXPRESS racks are about 80 inches tall by 33 inches deep by 41 inches wide (roughly the size of a REVCO freezer) and can provide basic resources such as power to a variety of modular experiments. Each EXPRESS rack contains eight middeck locker equivalents and two storage drawers.
Increment:
The length of time between shuttle flights that transfer research equipment and samples to the ISS. For research planning purposes, this is assumed to be approximately 100 days.
Incubator:
A device which maintains controlled environmental conditions, especially providing warmth for cultivation of cell cultures or coolness for preservation of cell culture samples.
Life Sciences Division:
The unit at NASA that aims to define, direct, support, and evaluate science and technology programs in space life sciences to enable the human exploration and development of space. Main focus is on the fundamental role of gravity, cosmic radiation, isolation and confinement on the vital biological, chemical, physical and psychological processes of living systems in space, on other planetary bodies and on Earth.
Macromolecule:
A macromolecule is a polymer, especially one composed of more than 100 repeated monomers (which are single chemical units). This report focuses on biological macromolecules, such as proteins, proteins with DNA, and RNA.
Medium:
A culture or growth medium contains nutrients and provides a favorable environment for the growth of cells or tissues.
Microgravity:
When biotechnology experiments are performed on the space shuttle or the International Space Station, the gravitational force experienced by the cells or the protein crystals is not exactly zero, but it is much less than the gravitational force experienced on Earth. On the ISS, researchers expect to be able to conduct experiments for which the gravitational force is approximately one-millionth of what it is on Earth.
Microgravity Research Division:
The unit at NASA that contains research on the behavior of systems in the microgravity environment. Includes five disciplines: Biotechnology, Combustion Science, Fluid Physics and Transport Phenomena, Fundamental Physics, and Materials Science. The Biotechnology program contains the work on protein crystal growth and cell science discussed in this report.
Middeck Locker Equivalent:
Standard size of transport and experimental units on the space shuttle and the space station. Each MLE is 18.2″ wide by 10.7″ high by 20.4″ deep, and the modular equipment that fits in the MLE can weigh approximately 60-70 pounds. Eight MLEs fit in each EXPRESS rack.
Mosaicity:
A measure of the misalignment between small coherent blocks of individual molecules within a protein crystal. Lower mosaicity results in higher quality X-ray diffraction data.
NASA Research Announcement:
Solicitation and instructions for grant applications for NASA funding for ground and flight experiments. Released approximately every two years.
Resolution:
A measure of how much detail can be obtained from X-ray diffraction data used for structure determination of protein crystals. The resolution, typically measured in angstroms, is specifically the minimal Bragg spacing to which diffraction measurements can be obtained. The smaller the resolution is, the more details are revealed about the protein structure.
Rotating-Wall Perfused System:
Instrument that houses a rotating-wall vessel and associated support equipment for experiments on the ISS.
Rotating-Wall Vessel:
Designed for culturing cells in a low-shear, low-turbulence environment. On Earth, the rotating walls set up laminar flow in order to randomize the force vector felt by the cell or tissue cultures. In space, the rotation produces Couette flow to augment mass trasport. Also known as a bioreactor.
Space Products Development Office:
Responsible for NASA's commercial product development program to encourage and increase the United States' industry involvement and investment in space-based materials processing and biotechnology technologies. Oversees the Commercial Space Centers, such as the Center for Macromolecular Crystallography at the University of Alabama at Birmingham. Responsible for the XCF, which is in development at this center.
Synchrotron:
A facility that produces high energy X rays by accelerating electrons along a circular path. These X rays are used for diffraction studies of macromolecular crystals to gather data that can be employed to determine the macromolecule's structure.
X-ray Crystallography Facility:
A multipurpose facility designed to provide and coordinate all aspects of protein crystal growth experiments on ISS: sample growth, monitoring, mounting, freezing, and X-ray diffraction. In development at the Center for Macromolecular Crystallography at the University of Alabama at Birmingham.
