Crystal structure of the putative adapter protein MTH1859.
MTH1859 from Methanobacterium thermoautotrophicum is a 77 residue protein representing a conserved family of functionally uncharacterized proteins. We solved the crystal structure of MTH1859 by single wavelength anomalous diffraction phasing using selenomethionine labeled protein. MTH1859 adopts a mainly anti-parallel all-beta-fold. The beta-sheet is heavily bent to form a U-structure that is closed through a loop. The monomer structure possesses similarities to the photoreaction center (PRC) domain fold, but the protein employs a unique oligomerization scheme. Two monomers of MTH1859 occupy the asymmetric unit and dimerize in a head-to-head fashion. Crystal packing interactions identify a second protein-protein interaction interface at the MTH1859 tails which can simultaneously bind two partner molecules. These interactions lead to the formation of a honeycomb structure and suggest that the family of MTH1859-like proteins might function as adapters for protein complex assembly.
Department of Biochemistry, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA.
Hong
H
Ye
Tzu-Chao
TC
Chen
Xiaohui
X
Xu
Micha
M
Pennycooke
Hao
H
Wu
Clemens
C
Steegborn
D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D003001:Cloning, Molecular; D018360:Crystallography, X-Ray; D017014:Methanobacterium / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid
D048868:Adaptor Proteins, Signal Transducing; D001426:Bacterial Proteins