X-ray structure from ITQB in Science

Oeiras, 17/02/06

A team lead by Carlos Frazao, researcher at ITQB, has published a paper in this week’s edition of Science. Claudio Gomes, also researcher at ITQB (Laboratório Associado) is the second author of this paper. Apart from the scientific significance of their findings the symmetry of the published structure makes it particularly appealing, almost artistic.

Microbial Mobilization of Elemental Sulfur

Microbial oxidation of elemental sulfur is important in the global sulfur cycle, but little is known about the mechanism of this reaction. Urich et al. (p. 996) have determined a 1.7 angstrom resolution structure of a sulfur oxygenase reductase from a thermoacidophilic archaeon. A spherical, positively charged reaction chamber forms from 24 monomers. Linear sulfur probably enters through apolar channels and is bound by a cysteine persulfide in one of the 24 active sites. This sulfane sulfur chain is the substrate of disproportionation and oxygenation at a nearby mononuclear nonheme iron.

Original Paper X-ray Structure of a Self-Compartmentalizing Sulfur Cycle Metalloenzyme