Lawrence Berkeley National Laboratory
X-ray diffraction analysis and in vitro characterization of the UAM2 protein from Oryza sativa.
- Author(s): Welner, Ditte Hededam
- Tsai, Alex Yi Lin
- DeGiovanni, Andy M
- Scheller, Henrik Vibe
- Adams, Paul D
- et al.
Published Web Locationhttp://journals.iucr.org/f/issues/2017/04/00/hv5349/hv5349.pdf
The role of seemingly non-enzymatic proteins in complexes interconverting UDP-arabinopyranose and UDP-arabinofuranose (UDP-arabinosemutases; UAMs) in the plant cytosol remains unknown. To shed light on their function, crystallographic and functional studies of the seemingly non-enzymatic UAM2 protein from Oryza sativa (OsUAM2) were undertaken. Here, X-ray diffraction data are reported, as well as analysis of the oligomeric state in the crystal and in solution. OsUAM2 crystallizes readily but forms highly radiation-sensitive crystals with limited diffraction power, requiring careful low-dose vector data acquisition. Using size-exclusion chromatography, it is shown that the protein is monomeric in solution. Finally, limited proteolysis was employed to demonstrate DTT-enhanced proteolytic digestion, indicating the existence of at least one intramolecular disulfide bridge or, alternatively, a requirement for a structural metal ion.