The dimeric Repressor of Primer (Rop) protein, a widely used model system for the study of coiled-coil 4-α-helical bundles, is characterized by a remarkable structural plasticity. Loop region mutations lead to a wide range of topologies, folding states, and altered physicochemical properties. A protein-folding study of Rop and several loop variants has identified specific residues and sequences that are linked to the observed structural plasticity.
View Article and Find Full Text PDFGeranylgeranylglyceryl phosphate synthase (GGGPS) family enzymes catalyse the formation of an ether bond between glycerol-1-phosphate and polyprenyl diphosphates. They are essential for the biosynthesis of archaeal membrane lipids, but also occur in bacterial species, albeit with unknown physiological function. It has been known that there exist two phylogenetic groups (I and II) of GGGPS family enzymes, but a comprehensive study has been missing.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
June 2012
The LysR-type transcriptional regulator MvfR plays a critical role in Pseudomonas aeruginosa pathogenicity via the transcriptional regulation of multiple quorum-sensing-regulated virulence factors. The protein also controls pathogenic type VI secretion loci. MvfRC87, a 242-residue C-terminal segment of MvfR, was produced in Escherichia coli, purified and crystallized.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
August 2010
Crystallographic binding studies have been carried out to probe the active-site binding properties of a monomeric variant (A-TIM) of triosephosphate isomerase (TIM). These binding studies are part of a structure-based directed-evolution project aimed towards changing the substrate specificity of monomeric TIM and are therefore aimed at finding binders which are substrate-like molecules. A-TIM has a modified more extended binding pocket between loop-7 and loop-8 compared with wild-type TIM.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
May 2008
Rop is the paradigm of a canonical four-alpha-helical bundle. Its loop region has attracted considerable interest because a single alanine-to-proline substitution (A31P) in the loop is sufficient to change the topology of this small protein. In order to further analyse the loop region as a possible folding-control element, the double mutant D30P/A31G (RopPG) was produced, purified and crystallized.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
March 2008
The peptidoglycan N-acetylglucosamine (GlcNAc) deacetylase BC1960 from Bacillus cereus (EC 3.5.1.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
January 2007
The DNA methyltransferase M.BseCI from Bacillus stearothermophilus (EC 2.1.
View Article and Find Full Text PDFpH is one of the key parameters that affect the stability and function of proteins. We have studied the effect of pH on the pyridoxal-5'-phosphate-dependent enzyme phosphoserine aminotransferase produced by the facultative alkaliphile Bacillus circulans ssp. alkalophilus using thermodynamic and crystallographic analysis.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
May 2005
Polyhydroxyalkanoates (PHA) are biodegradable polyesters that have attracted commercial and academic interest as environmentally friendly materials. A number of enzymes are able to degrade polyhydroxyalkanoates to water-soluble products. PhaZ7 poly(3-hydroxybutyrate) (PHB) depolymerase (EC 3.
View Article and Find Full Text PDFThe crystal structure of the vitamin B(6)-dependent enzyme phosphoserine aminotransferase from the obligatory alkaliphile Bacillus alcalophilus has been determined at 1.08 A resolution. The model was refined to an R-factor of 11.
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