The guanine cap of human guanylate-binding protein 1 is responsible for dimerization and self-activation of GTP hydrolysis.

Human guanylate-binding protein 1 (hGBP1) belongs to the superfamily of large, dynamin-related GTPases. The expression of hGBP1 is induced by stimulation with interferons (mainly interferon-γ), and it plays a role in different cellular responses to inflammatory cytokines, e.g.

Biochemical properties of the human guanylate binding protein 5 and a tumor-specific truncated splice variant.

The human guanylate binding protein 5 (hGBP5) belongs to the family of interferon-gamma-inducible large GTPases, which are well known for their high induction by pro-inflammatory cytokines. The cellular role of this protein family is unclear at this point, but there are indications for antiviral and antibacterial activity of hGBP1. hGBP5 exists in three splice variants, forming two different proteins, of which the tumor-specific one is C-terminally truncated by 97 amino acids, and therefore lacks the CaaX motif for geranylgeranylation.

Structure and function of the FeoB G-domain from Methanococcus jannaschii.

FeoB in bacteria and archaea is involved in the uptake of ferrous iron (Fe(2+)), an important cofactor in biological electron transfer and catalysis. Unlike any other known prokaryotic membrane protein, FeoB contains a GTP-binding domain at its N-terminus. We determined high-resolution X-ray structures of the FeoB G-domain from Methanococcus jannaschii with and without bound GDP or Mg(2+)-GppNHp.

Catalytic core of a membrane-associated eukaryotic polyphosphate polymerase.

Polyphosphate (polyP) occurs ubiquitously in cells, but its functions are poorly understood and its synthesis has only been characterized in bacteria. Using x-ray crystallography, we identified a eukaryotic polyphosphate polymerase within the membrane-integral vacuolar transporter chaperone (VTC) complex. A 2.