Search

The protein encoded by the MJ0754 gene from the archaeon Methanococcus jannaschii DSM 2661 is an unknown hypothetical protein. Two recombinant proteins, MJ0754 (residues 1-185) and MJ0754t (a truncated form of MJ0754, residues 11-185), were cloned from MJ0754, overexpressed as His-tag fusion proteins and purified. The crystals were found to grow under two different conditions and to have two different shapes. The crystal of MJ0754 belonged to space group P61, with unit-cell parameters a = b = 127.015, c = 48.929 Å, a calculated Matthews coefficient of 2.85 Å3 Da−1 and two molecules per asymmetric unit. The crystal of MJ0754t belonged to space group C2221, with unit-cell parameters a = 51.915, b = 79.122, c = 93.869 Å, a calculated Matthews coefficient of 2.41 Å3 Da−1 and one molecule per asymmetric unit. The SeMet-labelled P61 crystal diffracted to a resolution of 3.1 Å, while the native C2221 crystal diffracted to 1.3 Å resolution. [ABSTRACT FROM AUTHOR]

Probable tRNA-modification GTPase (TrmE) is a guanine nucleotide-binding protein that is conserved between bacteria and humans. GTPase hydrolyzes GTP and plays a pivotal role in signalling pathways. In this study, TrmE from Staphylococcus aureus was overexpressed in Escherichia coli. The enzyme was found to crystallize at 295 K when ammonium sulfate was used as a precipitant. X-ray diffraction data were collected to 2.9 Å resolution from the crystallized enzyme using synchrotron radiation. The crystal was found to belong to the cubic space group I23, with unit-cell parameters a = b = c = 229.47 Å, α = β = γ = 90°. The crystal is likely to contain four monomers in the asymmetric unit, with a corresponding VM of 2.4 Å3 Da−1 and a solvent content of 50%. [ABSTRACT FROM AUTHOR]