APCF-LYSOZYME (MUNOZ)
Initial analysis of crystals returned from station support the findings of earlier APCF flights:
comparative crystallographic analysis indicates that space-grown crystals are superior in every
way to control-groups crystals grown on Earth under identical conditions (except the critical
space environment). Crystals grown in microgravity generally have improved morphology,
larger volume, higher diffraction limit, and lower mosaicity as compared to Earth-grown
crystals. The researchers reported that the electron-density maps calculated from different
diffraction data contained considerably more detail, allowing them to produce more accurate 3-
D models (Vergara 2005).
The APCF hardware performed well during ISS Expedition 3
with very few anomalies. APCF-Camelids, APCF-Crystal
Quality, APCF- Crystal Growth, APCF- Lysozyme, APCF-
Octarellins and APCF-PPG10 all produced excellent quality
crystals that had better resolution and other optical
properties than those grown on Earth. APCF-Lipoprotein
successfully produced crystals but they did not achieve the
expected level of resolution. APCF-Rhodopsin had slight
technical problems that prevented the formation of
suitable crystals. The more recently developed Granada
Crystallization Facility (GCF) makes it possible to carry out a
larger number of experiments. To optimally use the
results from these experiments, it was necessary to
visualize the crystal development throughout the
forming process. The Protein Microscope for the
International Space Station (PromISS) was developed
for observation by digital holography. This method enabled researchers to evaluate the initial
appearance of crystals, their growth rates, and the movement of crystals. Adjustments need to
be made to reduce the sensitivity of the PromISS to vibrations aboard the ISS and also to have
the crystals form within the observation time.
Well defracting crystals prepared in space have 2 purposes: understanding the gravity-
dependent phenomena (such as nucleation and growth mechanisms) and structural
determination. Each new high-resolution structure may become the start of a cascade of
investigations to unravel the complexity of cellular events like growth, division, differentiation,
communication, motility, death, and their role in the development of multicellular organisms.
This may accelerate the structure-based design and redesign of drugs targeting pathogens,
diseases, and degenerative cellular processes as well as of protein and nucleic acid leading to
custom enzymes, ribozymes, or inhibitors to treat diseases.
APCF-OCTARELLINS (MARTIAL)
Data for this investigation was inconclusive.
Ribbon Structure showing the main chain
de novo design o the idealized alpha/beta-
barrel. This scaffold has been used for the
design of the next generation octarellin.
NASA image.