Structural insights into the extracytoplasmic thiamine-binding lipoprotein p37 of Mycoplasma hyorhinis.
The Mycoplasma hyorhinis protein p37 has been implicated in tumorigenic transformation for more than 20 years. Though there are many speculations as to its function, based solely on sequence homology, the issue has remained unresolved. Presented here is the 1.6-A-resolution refined crystal structure of M. hyorhinis p37, renamed the extracytoplasmic thiamine-binding lipoprotein (Cypl). The structure shows thiamine pyrophosphate (TPP) and two calcium ions are bound to Cypl and give the first insights into possible functions of the Cypl-like family of proteins. Sequence alignments of Cypl-like proteins between several different species of mycoplasma show that the thiamine-binding site is likely conserved and structural alignments reveal the similarity of Cypl to various binding proteins. While the experimentally determined function of Cypl remains unknown, the structure shows that the protein is a TPP-binding protein, opening up many avenues for future mechanistic studies and making Cypl a possible target for combating mycoplasma infections and tumorigenic transformation.
Sippel
Katherine H
KH
Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA.
Robbins
Arthur H
AH
Reutzel
Robbie
R
Boehlein
Susan K
SK
Namiki
Kazunori
K
Goodison
Steve
S
Agbandje-McKenna
Mavis
M
Rosser
Charles J
CJ
McKenna
Robert
R
D001426:Bacterial Proteins / Q000737:chemistry*; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D002352:Carrier Proteins / Q000737:chemistry*; D002413:Cations, Divalent / Q000378:metabolism; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D008074:Lipoproteins / Q000737:chemistry*; D008958:Models, Molecular; D045790:Mycoplasma hyorhinis / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D013835:Thiamine Pyrophosphate / Q000378:metabolism
D001426:Bacterial Proteins; D002352:Carrier Proteins; D002413:Cations, Divalent; D008074:Lipoproteins; C026989:thiamine-binding protein; D013835:Thiamine Pyrophosphate; D002118:Calcium