NASA Scientific and Technical Aerospace Reports

(+)-atropine. This report describes the analysis of obidoxime (200 ng/ml- 50 micro g/ml) with capillary electrophoresis and
atropine (0.5 ng/ml- 75 ng/ml) with LC-MS-MS.
Author
Atropine; Chemical Analysis; Chlorides; Plasma Chemistry
20040111413 NASA Marshall Space Flight Center, Huntsville, AL, USA, National Space Science and Technology Center,
Huntsville, AL, USA
Oxygen Effect on the Low Temperature Tolerance of Facultative Anaerobes from Antarctica, Alaska, and Patagonia
Pikuta, Elena V.; Hoover, Richard B.; [2004]; 1 pp.; In English; SPIE 49th Annual Meeting, 2-6 Aug. 2004, Denver, CO,
USA; No Copyright; Avail: CASI; A01, Hardcopy
Psychrotolerance as an adaptation to survival in extreme environments is widespread among many of the mesophilic
microorganisms. Red-ox potential, pH and salinity could significantly alter the features of ecosystems by providing liquid
water at subzero temperatures. Furthermore, organisms can respond to temperature changes by several known mechanisms,
including changing the conformation capacities of constitutional proteins or by the synthesis of mucopolysaccharides around
the cell wall and membrane. Such protective mechanisms make it possible for cells to not only passively survive
low-temperature in a state of anabiosis, but also to be capable of actively metabolizing substrates and reproducing normally.
The physiological and biochemical characteristics of species as well as genetics could be remarkably changed due to -on and
surviving m extreme environments. The cold shock genes for some of the studied strains of psychrotolerant facultative
anaerobes already were published In this paper we present experimental data for psychrotolerant facultative anaerobes isolated
from geographically different cold regions of our planet. We show the growth response on the changing of anaerobic
conditions to aerobic with cultivation at subzero temperatures.
Author
Oxygen; Low Temperature Environments; Anaerobes; Microorganisms; Biochemistry; Survival
20040111419 BAE Systems Analytical Solutions, Inc., Huntsville, AL, USA
Magnetic Control of Convection during Protein Crystallization
Ramachandran, N.; Leslie, F. W.; [2004]; 1 pp.; In English; International Conference on Crystal Growth, 9-13 Aug. 2004,
Grenoble, France; Original contains black and white illustrations
Contract(s)/Grant(s): NAS8-02096; No Copyright; Avail: Other Sources; Abstract Only
An important component in biotechnology, particularly in the area of protein engineering and rational drug design is the
knowledge of the precise three-dimensional molecular structure of proteins. The quality of structural information obtained
from X-ray diffraction methods is directly dependent on the degree of perfection of the protein crystals. As a consequence,
the growth of high quality macromolecular Crystals for diffraction analyses has been the central focus for bio-chemists,
biologists, and bioengineers. Macromolecular crystals are obtained from solutions that contain the crystallizing species in
equilibrium with higher aggregates, ions, precipitants, other possible phases of the protein, foreign particles, the walls of
container, and a likely host of other impurities. By changing transport modes in general, i.e., reduction of convection and
Sedimentation as is achieved in ‘microgravity", we have been able to dramatically affect the movement and distribution
of macromolecules in the fluid, and thus their transport, fodonofcrystal nuclei, and adsorption to the crystal surface. While
a limited number of high quality crystals from space flights have been obtained, as the recent National Research Council
(NRC) review of the NASA microgravity crystallization program pointed out, the scientific approach and research in
crystallization of proteins has been mainly empirical yielding inconclusive results. We postulate that we can reduce convection
in ground-based experiments and we can understand the different aspects of convection control through the use of strong
magnetic fields and field gradients. We postulate that limited convection in a magnetic field will provide the environment for
the growth of high quality crystals. The approach exploits the variation of fluid magnetic susceptibility with counteracts on
for this purpose and the convective damping is realized by appropriately positioning the crystal growth cell so that the
magnetic susceptibility force counteract terrestrial gravity. The genera1 objective is to test the hypothesis of convective control
using a strong magnetic field and magnetic field gradient and to understand the nature of the various forces that come into play.
Specifically we aim to delineate causative factors and to quantify them through experiments, analysis and numerical modeling.
The paper will report on the experimental results using paramagentic salts and solutions in magnetic fields and compare them
to analyticalpr~ctions.
Derived from text
Magnetic Control; Crystallization; Convection; Bioengineering; Environmental Quality; Macromolecules; Microgravity;
Protein Crystal Growth
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