Crystal structure of a hypothetical protein, TM841 of Thermotoga maritima, reveals its function as a fatty acid-binding protein.
We determined the three-dimensional (3D) crystal structure of protein TM841, a protein product from a hypothetical open-reading frame in the genome of the hyperthermophile bacterium Thermotoga maritima, to 2.0 A resolution. The protein belongs to a large protein family, DegV or COG1307 of unknown function. The 35 kDa protein consists of two separate domains, with low-level structural resemblance to domains from other proteins with known 3D structures. These structural homologies, however, provided no clues for the function of TM841. But the electron density maps revealed clear density for a bound fatty-acid molecule in a pocket between the two protein domains. The structure indicates that TM841 has the molecular function of fatty-acid binding and may play a role in the cellular functions of fatty acid transport or metabolism.
Schulze-Gahmen
Ursula
U
Physical Biosciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720-5230, USA.
Pelaschier
Joanne
J
Yokota
Hisao
H
Kim
Rosalind
R
Kim
Sung-Hou
SH
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000502:physiology; D002352:Carrier Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D050556:Fatty Acid-Binding Proteins; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins; D016415:Sequence Alignment; D020124:Thermotoga maritima / Q000737:chemistry*
D001426:Bacterial Proteins; D002352:Carrier Proteins; D050556:Fatty Acid-Binding Proteins; D009363:Neoplasm Proteins