Engineering an improved crystal contact across a solvent-mediated interface of human fibroblast growth factor 1.
Large-volume protein crystals are a prerequisite for neutron diffraction studies and their production represents a bottleneck in obtaining neutron structures. Many protein crystals that permit the collection of high-resolution X-ray diffraction data are inappropriate for neutron diffraction owing to a plate-type morphology that limits the crystal volume. Human fibroblast growth factor 1 crystallizes in a plate morphology that yields atomic resolution X-ray diffraction data but has insufficient volume for neutron diffraction. The thin physical dimension has been identified as corresponding to the b cell edge and the X-ray structure identified a solvent-mediated crystal contact adjacent to position Glu81 that was hypothesized to limit efficient crystal growth in this dimension. In this report, a series of mutations at this crystal contact designed to both reduce side-chain entropy and replace the solvent-mediated interface with direct side-chain contacts are reported. The results suggest that improved crystal growth is achieved upon the introduction of direct crystal contacts, while little improvement is observed with side-chain entropy-reducing mutations alone.
Meher
Akshaya K
AK
Department of Biomedical Sciences, Florida State University, Tallahassee, 32306-4300, USA.
Blaber
Sachiko I
SI
Lee
Jihun
J
Honjo
Ejiro
E
Kuroki
Ryota
R
Blaber
Michael
M
D003460:Crystallization / Q000379:methods*; D018360:Crystallography, X-Ray; D016220:Fibroblast Growth Factor 1 / Q000737:chemistry* / Q000235:genetics; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016296:Mutagenesis; D033363:Neutron Diffraction; D011487:Protein Conformation; D015202:Protein Engineering / Q000379:methods*; D012997:Solvents / Q000737:chemistry*; D014961:X-Ray Diffraction
D012997:Solvents; D016220:Fibroblast Growth Factor 1