Open AccessCrystallization and preliminary crystallographic analysis of mannosyl‐3‐phosphoglycerate synthase from Rubrobacter xylanophilus
Author(s) -
SáMoura Bebiana,
Albuquerque Luciana,
Empadinhas Nuno,
Da Costa Milton S.,
Pereira Pedro José Barbosa,
MacedoRibeiro Sandra
Publication year - 2008
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309108021490
Subject(s) - thermophile , gene , biochemistry , archaea , biology , enzyme , escherichia coli , atp synthase , bacteria , peptide sequence , crystallization , crystallography , chemistry , genetics , organic chemistry
Rubrobacter xylanophilus is the only Gram‐positive bacterium known to synthesize the compatible solute mannosylglycerate (MG), which is commonly found in hyperthermophilic archaea and some thermophilic bacteria. Unlike the salt‐dependent pattern of accumulation observed in (hyper)thermophiles, in R. xylanophilus MG accumulates constitutively. The synthesis of MG in R. xylanophilus was tracked from GDP‐mannose and 3‐phosphoglycerate, but the genome sequence of the organism failed to reveal any of the genes known to be involved in this pathway. The native enzyme was purified and its N‐terminal sequence was used to identify the corresponding gene ( mpgS ) in the genome of R. xylanophilus . The gene encodes a highly divergent mannosyl‐3‐phosphoglycerate synthase (MpgS) without relevant sequence homology to known mannosylphosphoglycerate synthases. In order to understand the specificity and enzymatic mechanism of this novel enzyme, it was expressed in Escherichia coli , purified and crystallized. The crystals thus obtained belonged to the hexagonal space group P 6 5 22 and contained two protein molecules per asymmetric unit. The structure was solved by SIRAS using a mercury derivative.