Acta Crystallogr Sect F Struct Biol Cryst Commun
May 2007
Using single-wavelength anomalous dispersion data obtained from a gold-derivatized crystal, the X-ray crystal structure of the protein 067745_AQUAE from the prokaryotic organism Aquifex aeolicus has been determined to a resolution of 2.0 A. Amino-acid residues 1-371 of the 44 kDa protein were identified by Pfam as an HD domain and a member of the metal-dependent phosphohydrolase superfamily (accession No.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
July 2005
NAD kinase is the only known enzyme that catalyzes the formation of NADP, a coenzyme involved in most anabolic reactions and in the antioxidant defense system. Despite its importance, very little is known regarding the mechanism of catalysis and only recently have several NAD kinase structures been deposited in the PDB. Here, an independent investigation of the crystal structure of inorganic polyphosphate/ATP-NAD kinase, PPNK_THEMA, a protein from Thermotoga maritima, is reported at a resolution of 2.
View Article and Find Full Text PDFThe crystal structure of a hypothetical protein, TM1457, from Thermotoga maritima has been determined at 2.0A resolution. TM1457 belongs to the DUF464 family (57 members) for which there is no known function.
View Article and Find Full Text PDFThe initial aim of the Berkeley Structural Genomics Center is to obtain a near-complete structural complement of two minimal organisms, closely related pathogens Mycoplasma genitalium and M. pneumoniae. The former has fewer than 500 genes and the latter fewer than 700 genes.
View Article and Find Full Text PDFAll cells have a defense mechanism against a sudden heat-shock stress. Commonly, they express a set of proteins that protect cellular proteins from being denatured by heat. Among them, GroE and DnaK chaperones are representative defending systems, and their transcription is regulated by a heat-shock repressor protein HrcA.
View Article and Find Full Text PDFThe phoU gene of Aquifex aeolicus encodes a protein called PHOU_AQUAE with sequence similarity to the PhoU protein of Escherichia coli. Despite the fact that there is a large number of family members (more than 300) attributed to almost all known bacteria and despite PHOU_AQUAE's association with the regulation of genes for phosphate metabolism, the nature of its regulatory function is not well understood. Nearly one-half of these PhoU-like proteins, including both PHOU_AQUAE and the one from E.
View Article and Find Full Text PDFWe have determined the crystal structure of nicotinate phosphoribosyltransferase from Themoplasma acidophilum (TaNAPRTase). The TaNAPRTase has three domains, an N-terminal domain, a central functional domain, and a unique C-terminal domain. The crystal structure revealed that the functional domain has a type II phosphoribosyltransferase fold that may be a common architecture for both nicotinic acid and quinolinic acid (QA) phosphoribosyltransferases (PRTase) despite low sequence similarity between them.
View Article and Find Full Text PDFType I restriction-modification enzymes are differentiated from type II and type III enzymes by their recognition of two specific dsDNA sequences separated by a given spacer and cleaving DNA randomly away from the recognition sites. They are oligomeric proteins formed by three subunits: a specificity subunit, a methylation subunit, and a restriction subunit. We solved the crystal structure of a specificity subunit from Methanococcus jannaschii at 2.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
September 2004
One of the most critical steps in the preparation of protein samples for structural studies by X-ray crystallography is to obtain biochemically pure and conformationally homogenous protein samples. Very often, the purified sample does not meet these qualifications and therefore does not crystallize. A screening method, Optimum Solubility Screen, has been developed that consists of two steps.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2004
We have determined the crystal structure of the GDP complex of the YjeQ protein from Thermotoga maritima (TmYjeQ), a member of the YjeQ GTPase subfamaily. TmYjeQ, a homologue of Escherichia coli YjeQ, which is known to bind to the ribosome, is composed of three domains: an N-terminal oligonucleotide/oligosaccharide-binding fold domain, a central GTPase domain, and a C-terminal zinc-finger domain. The crystal structure of TmYjeQ reveals two interesting domains: a circularly permutated GTPase domain and an unusual zinc-finger domain.
View Article and Find Full Text PDFWe have determined the crystal structure of peptide chain release factor 1 (RF1) from Thermotoga maritima (gi 4981173) at 2.65 Angstrom resolution by selenomethionine single-wavelength anomalous dispersion (SAD) techniques. RF1 is a protein that recognizes stop codons and promotes the release of a nascent polypeptide from tRNA on the ribosome.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
May 2004
The crystal structure of an osmotically inducible protein (OsmC) from Escherichia coli has been determined at 2.4 A resolution. OsmC is a representative protein of the OsmC sequence family, which is composed of three sequence subfamilies.
View Article and Find Full Text PDFWe report the crystal structure of N-utilizing substance A protein (NusA) from Thermotoga maritima (TmNusA), a protein involved in transcriptional pausing, termination, and antitermination. TmNusA has an elongated rod-shaped structure consisting of an N-terminal domain (NTD, residues 1-132) and three RNA binding domains (RBD). The NTD consists of two subdomains, the globular head and the helical body domains, that comprise a unique three-dimensional structure that may be important for interacting with RNA polymerase.
View Article and Find Full Text PDFBiochem Biophys Res Commun
October 2003
SU9516 is a 3-substituted indolinone compound with demonstrated potent and selective inhibition toward cyclin dependent kinases (cdks). Here, we describe the kinetic characterization of this inhibition with respect to cdk2, 1, and 4, along with the crystal structure in complex with cdk2. The molecule is competitive with respect to ATP for cdk2/cyclin A, with a K(i) value of 0.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
July 2003
The crystal structure of a hypothetical protein AQ_1354 (gi 2983779) from the hyperthermophilic bacteria Aquifex aeolicus has been determined using X-ray crystallography. As found in many structural genomics studies, this protein is not associated with any known function based on its amino-acid sequence. PSI-BLAST analysis against a non-redundant sequence database gave 68 similar sequences referred to as 'conserved hypothetical proteins' from the uncharacterized protein family UPF0054 (accession No.
View Article and Find Full Text PDFWe have determined the crystal structure of a phosphatase with a unique substrate binding domain from Thermotoga maritima, TM0651 (gi 4981173), at 2.2 A resolution by selenomethionine single-wavelength anomalous diffraction (SAD) techniques. TM0651 is a member of the haloacid dehalogenase (HAD) superfamily, with sequence homology to trehalose-6-phosphate phosphatase and sucrose-6(F)-phosphate phosphohydrolase.
View Article and Find Full Text PDFPhosphoserine phosphatase (PSP) is a member of a large class of enzymes that catalyze phosphoester hydrolysis using a phosphoaspartate-enzyme intermediate. PSP is a likely regulator of the steady-state d-serine level in the brain, which is a critical co-agonist of the N-methyl-d-aspartate type of glutamate receptors. Here, we present high-resolution (1.
View Article and Find Full Text PDFObjective: The retroviral oncogene v-Cbl causes pre-B cell lymphomas and myeloid leukemias in mice, and its Drosophila homologue is oncogenic, causing enhanced receptor tyrosine kinase signaling. The human Cbl gene resides at 11q23. The aim of this study is to determine the effect of oncogenic Cbl on growth-regulating responses.
View Article and Find Full Text PDFBackground: D-Serine is a co-agonist of the N-methyl-D-aspartate subtype of glutamate receptors, a major neurotransmitter receptor family in mammalian nervous systems. D-Serine is converted from L-serine, 90% of which is the product of the enzyme phosphoserine phosphatase (PSP). PSP from M.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2000
The intracellular protease from Pyrococcus horikoshii (PH1704) and PfpI from Pyrococcus furiosus are members of a class of intracellular proteases that have no sequence homology to any other known protease family. We report the crystal structure of PH1704 at 2.0-A resolution.
View Article and Find Full Text PDFFactor Xa plays a critical role in the formation of blood clots. This serine protease catalyzes the conversion of prothrombin to thrombin, the first joint step that links the intrinsic and extrinsic coagulation pathways. There is considerable interest in the development of factor Xa inhibitors for the intervention in thrombic diseases.
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