Structure–specificity relationships in Abp, a GH27 β-L-arabinopyranosidase from Geobacillus stearothermophilus T6

The three-dimensional structure of the GH27 arabinopyranosidase (Abp) from G. stearothermophilus T6 has been determined by molecular replacement, leading to full structural analysis of wild-type Abp (at 2.28 Å resolution) and its catalytic mutant Abp-D197A with (at 2.20 Å resolution) and without (at 2.30 Å resolution) a bound L-arabinose product. The structures demonstrate that Abp is a tetramer built of two pincer-like dimers, as also confirmed by SAXS.

Atomic resolution crystal structure of glutaredoxin 1 from Plasmodium falciparum and comparison with other glutaredoxins

The structure of glutaredoxin 1 from P. falciparum has been determined at atomic resolution and its unique structural features have been dissected.

A unique octameric structure of Axe2, an intracellular acetyl-xylooligosaccharide esterase from Geobacillus stearothermophilus

The crystal structure of the serine acetyl-xylooligosaccharide esterase from G. stearothermophilus (Axe2) has been determined by SAD techniques, allowing full structural analysis of the selenomethionine derivative Axe2-Se (at 1.70 Å resolution), the wild type Axe2-WT (1.85 Å) and the catalytic mutant Axe2-S15A (1.90 Å). The structures show that the enzyme forms a unique octameric torus built of two staggered cyclic tetramers, with four pairs of catalytic triads facing the central cavity. This octameric torus is further confirmed by gel-filtration, TEM and SAXS results.