“To develop and operate state-of-the-art facilities at the
Source for the study of the structure and dynamics of biological systems
under non-crystalline conditions similar to their functional states in living
BioCAT is organized as a National Institutes of Health (NIH) Biotechnology
Research Resource and is funded by the National Institute of General Biomedical Sciences (NIGMS).
Its primary research tool is a very high brightness X-ray
beam-line with an on-site biochemical preparation laboratory.
The research techniques that BioCAT supports are: Small- and Wide-angle
Diffraction from biological fibers, Small- and Wide-angle Scattering
(SAXS and WAXS) from macromolecules in solution, and X-ray microprobe imaging.
Many biological fibers such as muscle, hair, and
viruses have internal structure which can be probed with X-rays. Using
this technique, one can study the arrangement of proteins in muscle and
tendons. It may be used to understand human maladies such as heart disease
Solution Scattering (SAXS and WAXS)
Most proteins can not be crystallized. For those proteins, it is possible
to study their structure by analyzing the manner in which they scatter X-rays.
This technique is used to study how the proteins and nucleic acids in our cells
function as “molecular machines.”
When excited by High-energy X-rays, metals will fluoresce.
The spectrum of X-rays emitted from the metal depends on both the metal and its environment.
By illuminating a sample with tightly-focused X-rays, we can determine the content and
distribution of the metals present in the sample. By doing this in combination with Small- and
Wide-angle Diffraction, it is possible to correlate metal distribution with the distribution
of ordered regions in the sample. This technique is used to help us understand how the distribution
of metals (such as iron and zinc) in tissues affects such things as neurological diseases, normal
human development, heart disease, and cancer.