6-Fluoro-3-hydroxy-2-pyrazinecarboxamide (T-705) is a novel antiviral compound with broad activity against influenza virus and diverse RNA viruses. Its active metabolite, T-705-ribose-5′-triphosphate (T-705-RTP), is recognized by influenza virus RNA polymerase as a substrate competing with GTP, giving inhibition of viral RNA synthesis and lethal virus mutagenesis. Which enzymes perform the activation of T-705 is unknown. We here demonstrate that human hypoxanthine guanine phosphoribosyltransferase (HGPRT) converts T-705 into its ribose-5′-monophosphate (RMP) prior to formation of T-705-RTP. The anti-influenza virus activity of T-705 and T-1105 (3-hydroxy-2-pyrazinamide; the analogue lacking the 6-fluoro atom) was lost in HGPRT-deficient MDCK cells. This HGPRT dependency was confirmed in human HEK293T cells undergoing HGPRT-specific gene knockdown followed by influenza virus ribonucleoprotein reconstitution. Knockdown for adenine phosphoribosyltransferase (APRT) or nicotinamide ...
Thiopurine methyl transferase (TPMT) is an enzyme catalysing the methylation of 6-MP, competing with xanthine oxidase (XO) and hypoxanthine guanine phosphoribosyl transferase (HGPRT) to determine the amount of 6-MP metabolised to cytotoxic thioguanine nucleotides. Allelic polymorphisms in the TPMT gene predict the activity of the enzyme such that 1 in 10 of the population are heterozygous and have approximately 50% of normal activity, whilst 1 in 300 are completely deficient. As a result, these individuals are at high risk of severe myelosuppression. Conversely, individuals with very high levels of TPMT activity are hyper-methylators in whom clinical response is less likely. Prior knowledge of TPMT status avoids exposure of individuals with zero TPMT to potentially fatal treatment with AZA or 6-MP and provides one of the best examples of predictive pharmacogenetics in therapeutics. This article reviews literature on the role of TPMT measurement prior to treatment with thiopurines and provides ...
Malaria causes a worldwide annual mortality of about a million people.Rapidly evolving drug-resistant species of the parasite have created a pressing need for the identification of new drug targets and vaccine candidates. By developing fractionation protocols to enrich parasites from low-parasitemia patient samples, we have carried out the first ever proteomics analysis of clinical isolates of early stages of Plasmodium falciparum (Pf) and P. vivax. Patient-derived malarial parasites were directly processed and analyzed using shotgun proteomics approach using high-sensitivity MS for protein identification. Our study revealed about 100 parasite-coded gene products that included many known drug targets such as Pf hypoxanthine guanine phosphoribosyl transferase, Pf L-lactate dehydrogenase, and Plasmepsins. In addition,our study reports the expression of several parasite proteins in clinical ring stages that have never been reported in the ring stages of the laboratory-cultivated parasite strain. ...
Background The Plasmodium purine salvage enzyme, hypoxanthine guanine xanthine phosphoribosyl transferase (HGXPRT) can protect mice against Plasmodium yoelii pRBC challenge in a T cell-dependent manner and has, therefore, been proposed as a novel vaccine candidate. It is not known whether natural exposure to Plasmodium falciparum stimulates HGXPRT T cell reactivity in humans. Methods PBMC and plasma collected from malaria-exposed Indonesians during infection and 7-28 days after anti-malarial therapy, were assessed for HGXPRT recognition using CFSE proliferation, IFN? ELISPOT assay and ELISA. Results HGXPRT-specific T cell proliferation was found in 44% of patients during acute infection; in 80% of responders both CD4+ and CD8+ T cell subsets proliferated. Antigen-specific T cell proliferation was largely lost within 28 days of parasite clearance. HGXPRT-specific IFN-? production was more frequent 28 days after treatment than during acute infection. HGXPRT-specific plasma IgG was undetectable ...
The selection of T cell clones with mutations in the hypoxanthine guanine phosphoribosyltransferase (hprt) gene has been used to isolate T cells reactive to myelin basic protein (MBP) in patients with multiple sclerosis (MS). These T cell clones are activated in vivo, and are not found in healthy individuals. The third complementarity determining regions (CDR3) of the T cell receptor (TCR) alpha and beta chains are the putative contact sites for peptide fragments of MBP bound in the groove of the HLA molecule. The TCR V gene usage and CDR3s of these MBP-reactive hprt- T cell clones are homologous to TCRs from other T cells relevant to MS, including T cells causing experimental allergic encephalomyelitis (EAE) and T cells found in brain lesions and in the cerebrospinal fluid (CSF) of MS patients. In vivo activated MBP-reactive T cells in MS patients may be critical in the pathogenesis of MS ...
Our lab studies hypoxanthine guanine phosphoribosyltransferase and adenylosuccinate synthetase, enzymes involved in purine salvage in the malarial parasite, Plasmodium falciparum. We have also been studying enzymes involved in hemoglobin degradation and glycolysis. Enzymes of these essential pathways are of interest as targets for antimalarial chemotherapy. Protein engineering/ mutagenesis, spectroscopy and X- Ray crystallographic techniques are used to probe the structure, function and dynamics of these enzymes. Other aspects studied include substrate specificity,catalytic and kinetic mechanisms, and protein stability. Insights from these studies would aid the development of new antimalarials.. ...
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Obsolete - 5HHU: Plasmodium vivax hypoxanthine-guanine phosphoribosyltransferase in complex with [3R,4R]-4-guanin-9-yl-3-((S)-2-hydroxy-2-phosphonoethyl)oxy-1-N-(phosphonopropionyl)pyrrolidine
The measurement of the activity of the X-linked enzyme HPRT has been widely used as an indicator of X-chromosome activity during preimplantation development in the mouse. More recently, the concomitant measurement of the activity of the autosomally-encoded enzyme APRT has been used in an attempt to decrease the variability inherent in the measurement of enzyme activity from minute samples such as preimplantation embryos. In this study the use of the HPRT-deficient mouse mutant, Hprtb-m3, allowed the unequivocal identification of the parental origin of HPRT activity measured in embryos derived from crosses between wild-type mice, and mice which were homozygous or hemizygous for the Hprtb-m3 allele. Results were similar to those of a previous study, where oocyte-encoded HPRT activity accounted for about 10% of total HPRT activity at 76 hours post human chorionic gonadotrophin injection and the paternally-derived Hprt allele was shown to be transcriptionally active by the late 2-cell stage. In ...
This assay is used to detect mutations of the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene in Chinese hamster ovary (CHO) or lung (V79) fibroblasts.
Psueocyst of Pinna Etiology. -- Unknown. Thought to be due to repeated microtrauma. Clinical features. --Cystic swelling and minimal pain. Treatment. --For small cyst, needle aspiration and pressure bandage. It has to be repeated several times if needed. --In recurrent cases and for big cyst, incision and drainage followed by pressure bandage. Wedge excision is also recommended.. Erysepelas. Due to beta-haemolytic streptococci. It present as a bright red tender swelling which is demarcated from normal skin. Gout. Characterized by hyperurecimia due to the deficiency of hypo xanthine guanine phosphoribosyl transferase. In the ear, it affects the helix and presents as painful salmon pink subcutaneous nodules. On application of pressure, Sodium biurate exudate will comeout. When examined in polarized light, these crystals appear as negatively birefrigerant. Treatment. Analgesics, correction of underlying abnormality with colchicine or Allopurinol. Sebacious cyst of Pinna. It occurs because of ...
TY - JOUR. T1 - 3,4-Epoxy-1-butene, a reactive metabolite of 1,3-butadiene, induces somatic mutations in Xpc-null mice. AU - Wickliffe, Jeffrey K.. AU - Galbert, L. A.. AU - Ammenheuser, M. M.. AU - Herring, S. M.. AU - Xie, Jingwu. AU - Masters, O. E.. AU - Friedberg, E. C.. AU - Lloyd, R. S.. AU - Ward, J. B.. PY - 2006/1. Y1 - 2006/1. N2 - Xpc-null (Xpc-/-) mice, deficient in the global genome repair subpathway of nucleotide excision repair (NER-GGR), were exposed by intraperitoneal (IP) injection to a 300 mg/kg mutagenic dose of 3,4-epoxy-1-butene (EB), to investigate NERs potential role in repairing butadiene (BD) epoxide DNA lesions. Mutagenic sensitivity was assessed using the Hprt assay. Xpc-/- mice were significantly more sensitive to EB exposure, exhibiting an average 2.8-fold increase in Hprt mutant frequency (MF) relative to those of exposed Xpc+/+ (wild-type) mice. As a positive control for NER-GGR, additional mice were exposed by IP injection to a 150 mg/kg mutagenic dose of ...
Complete information for HPRT1 gene (Protein Coding), Hypoxanthine Phosphoribosyltransferase 1, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene Compendium
Complete information for HPRT1 gene (Protein Coding), Hypoxanthine Phosphoribosyltransferase 1, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene Compendium
The behaviour of human cells arrested in mitosis can be severely perturbed so as to generate numerous small minisegregants containing very few chromosomes. These cells can be separated according to size and DNA content and fused with intact cells. In this paper we describe the production and some properties of proliferating cell hybrids generated by fusion of human minisegregant cells derived from a HeLa strain with mouse A9 cells deficient in hypoxanthine phosphoribosyltransferase (HPRT, EC 2.4.2.8). The hybrids were shown to contain up to 10 human chromosomes including a single X. Independently derived hybrid clones were quantitatively characterized and compared with the parental phenotypes with respect to HPRT. Human isozymes of each of the 3 enzymes HPRT, glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and phosphoglycerate kinase (EC 2,7.2.3) were found. Tests to evaluate both structure and function of HPRT were utilized. The specific activity of HPRT of more than 10 hybrids tested was ...
Databases and software for the analysis of mutations at the human hprt, human p53, transgenic - bacterial lacI and transgenic lacZ ...
Myelin Basic Protein;Encephalomyelitis, Autoimmune, Experimental;Complementarity Determining Regions;Multiple Sclerosis;Hypoxanthine Phosphoribosyltransferase;T-Lymphocytes;Peptide Fragments;Receptors, Antigen, T-Cell, alpha-beta;Receptors ...
ID Q8X945_ECO57 Unreviewed; 182 AA. AC Q8X945; Q7AHP4; DT 01-MAR-2002, integrated into UniProtKB/TrEMBL. DT 01-MAR-2002, sequence version 1. DT 05-JUL-2017, entry version 113. DE SubName: Full=Hypoxanthine phosphoribosyltransferase {ECO:0000313,EMBL:AAG54429.1}; GN Name=hpt {ECO:0000313,EMBL:AAG54429.1}; GN OrderedLocusNames=ECs0129 {ECO:0000313,EMBL:BAB33552.1}, Z0136 GN {ECO:0000313,EMBL:AAG54429.1}; OS Escherichia coli O157:H7. OC Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales; OC Enterobacteriaceae; Escherichia. OX NCBI_TaxID=83334 {ECO:0000313,Proteomes:UP000002519}; RN [1] {ECO:0000313,EMBL:BAB33552.1, ECO:0000313,Proteomes:UP000000558} RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=O157:H7 / Sakai / RIMD 0509952 / EHEC RC {ECO:0000313,Proteomes:UP000000558}, and Sakai RC {ECO:0000313,EMBL:BAB33552.1}; RX PubMed=11258796; DOI=10.1093/dnares/8.1.11; RA Hayashi T., Makino K., Ohnishi M., Kurokawa K., Ishii K., Yokoyama K., RA Han C., Ohtsubo E., Nakayama K., ...
The PDB archive contains information about experimentally-determined structures of proteins, nucleic acids, and complex assemblies. As a member of the wwPDB, the RCSB PDB curates and annotates PDB data according to agreed upon standards. The RCSB PDB also provides a variety of tools and resources. Users can perform simple and advanced searches based on annotations relating to sequence, structure and function. These molecules are visualized, downloaded, and analyzed by users who range from students to specialized scientists.
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Seems like we will reach the 50 day MA based on this count. I bought back 1/2 short at 1079 and sold it back at at 1075. And will buy back at 1089 or the first sign of topping ...
... is caused by hyperuricemia (high serum levels of uric acid) due to a defective gene called the hypoxanthine guanine phosphoribosyltransferase. Patients with this syndrome are prone to have uric acid kidney stones and mental retardation. It is inherited as an X-linked recessive condition ...
Abstract : Lesch-Nyhan disease is a neurogenetic disorder caused by deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). Affected individuals exhibit a characteristic pattern of neurological and behavioral features attributable in part to dysfunction of basal ganglia dopamine systems. In the current studies, striatal dopamine loss was investigated in five different HPRT-deficient strains of mice carrying one of two different HPRT gene mutations. Caudoputamen dopamine concentrations were significantly reduced in all five of the strains, with deficits ranging from 50.7 to 61.1%. Mesolimbic dopamine was significantly reduced in only three of the five strains, with a range of 31.6-38.6%. The reduction of caudoputamen dopamine was age dependent, emerging between 4 and 12 weeks of age. Tyrosine hydroxylase and aromatic amino acid decarboxylase, two enzymes responsible for the synthesis of dopamine, were reduced by 22.4-37.3 and 22.2-43.1%, respectively. These ...
The favorable response to therapy, after the recognition of HPRT deficiency as the basis for the urolithiasis in 2 male siblings, contrasts sharply with the unfavorable outcome in their 2 uncles already in kidney failure. This underlines the importance of early diagnosis and therapy for the prognosis of partial HPRT deficiency. Lack of awareness of this disorder in many parts of mainland Europe is attributable to the fact that inherited defects of purine metabolism are relatively new diseases, the majority being discovered during the last 25 years. HPRT deficiency seems to be one of the most common enzyme defects of nucleotide metabolism among the 27 now described. This lack of awareness explains why it took so long for the diagnosis to be made in the uncles. Moreover, the elder, now 65, would have been 32 at the time the partial defect was first described by Kelly et al5 in 1967, when presumably renal function would already have been compromised. The development of renal disease in his nephew, ...
Mutation induction at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus has been studied in three human bladder tumour cell lines of varying radiosensitivity. U1-S40b, a radiosensitive mutant clone of MGH-U1, has been previously reported to show no difference in split-dose recovery or low dose-rate sparing, but to have an impaired repair fidelity when compared to its parent line. In this paper we have shown that U1-S40b is less mutable at the hprt locus at a similar level of survival. This may represent an increased incidence of severe or non-repairable lesions, making hprt- mutants poorly recoverable in U1-S40b when compared to MGH-U1. No difference was seen in mutation induction between MGH-U1 and RT112, another human bladder tumour cell line of similar radiosensitivity to MGH-U1.. ...
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TY - JOUR. T1 - Combined preconditioning and in vivo chemoselection with 6-thioguanine alone achieves highly efficient reconstitution of normal hematopoiesis with HPRT-deficient bone marrow. AU - Hacke, Katrin. AU - Szakmary, Akos. AU - Cuddihy, Andrew R.. AU - Rozengurt, Nora. AU - Lemp, Nathan A.. AU - Aubrecht, Jiri. AU - Lawson, Gregory W.. AU - Rao, Nagesh P.. AU - Crooks, Gay M.. AU - Schiestl, Robert H.. AU - Kasahara, Noriyuki. PY - 2012/1. Y1 - 2012/1. N2 - Purine analogs such as 6-thioguanine (6TG) cause myelotoxicity upon conversion into nucleotides by hypoxanthine-guanine phosphoribosyltransferase (HPRT). Here we have developed a novel and highly efficient strategy employing 6TG as a single agent for both conditioning and in vivo chemoselection of HPRT-deficient hematopoietic stem cells. The dose-response and time course of 6TG myelotoxicity were first compared in HPRT wild-type mice and HPRT-deficient transgenic mice. Dosage and schedule parameters were optimized to employ 6TG for ...
Resource #3: Purine and Pyrimidine Metabolism Disorders. http://www.merck.com/mmpe/sec19/ch296/ch296i.html. Main Focus: Under normal conditions, nucleotides act as components of cellular energy systems, signaling, and DNA and RNA production. However, when an enzyme has a defect causing it to malfunction leading to accumulation of compounds in blood, urine, or tissues, this can result in diseased states which can severely affect people and their everyday lives. This resource discusses several disorders of nucleotide metabolism; including disorders of purine salvage, purine nucleotide synthesis, purine catabolism, and pyrimidine metabolism. Not only is the nature of several deficiencies discussed, but diagnosis as well as possible treatment and diet adjustments are mentioned. Lesch-Nyhan syndrome is a disorder of purine salvage and results from a deficiency in the hypoxanthine-guanine phosphoribosyl transferase (HPRT) enzyme which normally aids in salvage pathway for hypoxanthine and guanine ...
Lesch-Nyhan Disease (LND) is a rare X-linked recessive metabolic and neurological syndrome due to the deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT). Besides its well known "housekeeping" function this purine salvage enzyme has revealed an unexpected role in neurodevelopment, unveiled by the peculiar neurological symptoms flanking hyperuricemia in LND: dystonia, choreoathetosis, compulsive self-injurious behaviour. Several lines of research have tried to find the molecular basis for the neurological phenotype after the disease was first described in 1964. Dopaminergic deficit was then found to underlie the neurologic symptoms but the aetiology for such alteration seemed inexplicable. A number of detailed studies in the last 50 years addressed the genetic, metabolic, cognitive, behavioral and anatomical features of this disease. Initial investigations seeked for accumulation of toxic metabolites or depletion of essential molecules to disclose potential connections between ...
Looking for the definition of HGPRT? Find out what is the full meaning of HGPRT on Abbreviations.com! Hypoxanthin guanine phosphoribosyl tranferase is one option -- get in to view more @ The Webs largest and most authoritative acronyms and abbreviations resource.
This technique consists of injecting the antigen of interest into a mouse and then taking, after a few weeks, the cells of the spleen. Among these cells are plasma cells secreting antibodies directed specifically against the chosen antigen. These plasma cells are fused with tumor cells called myeloma cells (immortal cells) thanks to the addition of polyethylene glycol (PEG) which induces membrane fusion and thus makes it possible to obtain hybridomas which have the capacity to multiply faster than normal body cells produce antibodies and develop specific antibodies indefinitely. The cells are then distributed in multiwell plates so that there is only one cell per well. In order to eliminate the plasma cells and the non-fused myeloma cells, a selective culture medium (HAT culture medium) will be used. Unfused plasma cells die quickly and the myeloma cells used which have a non-functional gene for an enzyme involved in the synthesis of nucleotides-hypoxanthine - guanine - phosphoribosyl - ...
Type II Toxoplasma gondii KU80 knockouts (Δku80) deficient in nonhomologous end joining were developed to delete the dominant pathway mediating random integration of targeting episomes. Gene targeting frequency in the type II Δku80 Δhxgprt strain measured at the orotate (OPRT) and the uracil (UPRT) phosphoribosyltransferase loci was highly efficient. To assess the potential of the type II Δku80 Δhxgprt strain to examine gene function affecting cyst biology and latent stages of infection, we targeted the deletion of four parasite antigen genes (GRA4, GRA6, ROP7, and tgd057) that encode characterized CD8(+) T cell epitopes that elicit corresponding antigen-specific CD8(+) T cell populations associated with control of infection ...
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The MLB Giants home sellout streak is at an MLB-best 240 games heading into a six-game, season-ending homestand, even though thousands of empty seats can be seen at AT&T Park, according to Alex Pavlovic of the SAN JOSE MERCURY NEWS. A sellout is official when the club distributes 41,500 tickets
The TriFECTa® RNAi kit does not include primers or PCR reagents for quantification of gene silencing.. We offer, separately, primer sets targeting human or mouse HPRT for use in SYBR® Green-based qPCR assays to monitor RNAi function following transfection with the HPRT-S1 Positive Control DsiRNA. For other human, mouse, or rat targets, consider using a predesigned PrimeTime® qPCR Assay. For other species, you can easily design a custom PrimeTime qPCR Assay using our free, online PrimerQuest® Tool.. The TriFECTa® Kit includes:. ...
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MetabolismPurines, pyrimidines, nucleosides, and nucleotidesSalvage of nucleosides and nucleotideshypoxanthine phosphoribosyltransferase (TIGR01203; EC 2.4.2.8; HMM-score: 44.3) ...
MetabolismPurines, pyrimidines, nucleosides, and nucleotidesSalvage of nucleosides and nucleotideshypoxanthine phosphoribosyltransferase (TIGR01203; EC 2.4.2.8; HMM-score: 22.2) ...
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Im also giving a longer retro-themed video illustrated talk in Lausanne at the Haute Ecole de Musique. Titled Everything Isnt A Remix it starts at at 2pm on Saturday 20th and is open to the general public. Info here ...
The DNA sequence of 11 in vivo-arising intragenic deletion junctions occurring in the hypoxanthine-guanine phosphoribosyltransferase (hprt) gene of human T-lymphocytes was determined. These delections ranged in size from 16 bp to 4057 bp. Extensive homology was not found at the deletion breaksites, indicating that non-homologous recombination was responsible for these deletions. Short regions of homology (1-3 nucleotides) at the deletion termini, which may direct the recombination event, were found in seven of the mutations. Only one mutation had an unaccounted for nucleotide at the junction. V(D)J recombinase recognition sequences, previously identified at other hprt deletion breaksites, were not present. Such features are also found at the deletion and translocation junctions of rearranged oncogenes and suppressor oncogenes. The ability to isolate and molecularly analyze deletion mutations occurring in vivo in peripheral human T-lymphocytes allows the assay of DNA breakage/rejoining events ...
We have investigated whether the presence of a DNA repair enzyme, 06-methylguanine-DNA-methyltransferase (MGMT), affects the nature of spontaneous mutations in a mammalian cell line. We compared spontaneous mutations in the adenine phosphoribosyl transferase gene of a Chinese hamster ovary (CHO) cell line that expressed 14,000 MGMT molecules/cell with those in the parental CHO cells lacking this DNA repair activity. The mutation rate/cell/generation of the two CHO cell lines did not differ significantly. However, DNA sequence analysis of spontaneous mutations in the MGMT-proficient CHO cell line revealed a complex picture. No significant difference from the parental CHO cells was found in the number or type of deletions, frame-shifts, multiple substitutions, or insertions. The frequency of G:C to T:A transversions was elevated in MGMT-proficient CHO cells. Expression of the enzyme considerably reduced G:C to A:T transitions (25% versus 8.3%). This latter result is the first evidence that this ...
Purine phosphoribosyltransferases, purine PRTs, are essential enzymes in the purine salvage pathway of living organisms. They are involved in the formation of C-N glycosidic bonds in purine nucleosides-50-monophosphate (NMPs) through the transfer of the 5-phosphoribosyl group from 5-phospho-a-D-ribosyl-1-pyrophosphate (PRPP) to purine nucleobases in the presence of Mg2þ. Herein, we report a simple and thermostable process for the one-pot, one-step synthesis of some purine NMPs using xanthine phosphoribosyltransferase, XPRT or adenine phosphoribosyltransferase, APRT2, from Thermus thermophilus HB8. In this sense, the cloning, expression and purification of TtXPRT and TtAPRT2 is described for the first time. Both genes, xprt and aprt2 were expressed as his-tagged enzymes in E. coli BL21(DE3) and purified by a heat-shock treatment, followed by Ni-affinity chromatography and a final, polishing gel-filtration chromatography. Biochemical characterization revealed TtXPRT as a tetramer and TtAPRT2 as a ...
6-Thioguanine-resistant mutants were induced in V79 Chinese hamster cells with 2-aminopurine, ICR-170 and hycanthone. Samples of mutants of different origin were treated with EMS or 1CR-170 and plated in HAT medium for selection of revertants. In the result, a significant fraction of HAT-resistant clones was not 6-thioguanine-sensitive as would have been expected from a genuine reversion to wild type.
Electrophilic arylnitrenium ions are considered to be the ultimate reactive intermediates formed by metabolism of mutagenic and carcinogenic arylamines and nitroarenes; they can produce DNA damage by reaction with specific sites on DNA bases. We studied their formation, reactivity and the genotoxic sequelae of their reactions with cellular DNA to understand the mutagenic and carcinogenic activities of arylamines and nitroarenes as a function of their chemical structure. Arylnitrenium ions were generated by the convenient non-metabolic procedure, photolysis of arylazides, to study the reactivity of these ultimate intermediates with DNA, by means of 32P-postlabelling, and the induction of histidine reversions in Salmonella, HPRT mutations and sister chromatid exchange in mammalian (Chinese hamster V79) cells. Good correlations were observed between the DNA-binding potencies and the mutagenic and SCE-inducing potencies of the arylnitrenium ions, among these the nitrenium ions derived from the heterocyclic
hi ml-stat-talks mike jordan is speaking at AT&T in october. ive been asked to pass along the announcement. for those of you who havent seen mike speak, he is worth the trip. best dave , Subject: AT&T Labs Research - Distinguished Speaker Seminar: October 5, 2011 - Michael I. Jordan , , -------------------------------------------------------------------------------------------------------- Announcement , AT&T Labs Research - DISTINGUISHED SPEAKER SEMINAR , , Title: Completely Random Measures for Bayesian Nonparametrics , , Speaker: Michael I. Jordan , , Affiliation: Department of Electrical Engineering and Computer Science , Department of Statistics , University of California, Berkeley , , , , Time and Place: Wednesday, October 5, 2011 3:30-4:30pm EDT , , FP C050 (Florham Park Auditorium) , Research Website: http://www.research.att.com/talks_and_events/2011_distinguished_speaker/m_jordan/m_jordan , , , Directions: http://www.research.att.com/evergreen/about_us/fp_directions.html , , Wine and ...
Metabolic cooperation assays were conducted with Chinese-hamster-V79 cells at three separate laboratories using standardized protocols and chemicals of known tumor promoting activity. Each laboratory used identical lots of test chemicals, solvents, serum, medium, and trypsin as well as a standard protocol. The chemicals to be tested were either known tumor promoters or had related chemical structu
Expression of HPRT1 (HGPRT, HPRT) in cerebral cortex tissue. Antibody staining with HPA006360 and CAB012200 in immunohistochemistry.
Hipoksantin fosforiboziltransferaza (EC 2.4.2.8, IMP pirofosforilaza, transfosforibozidaza, hipoksantin---guanin fosforiboziltransferaza, guaninska fosforiboziltransferaza, GPRT, HPRT, guanozin 5-fosfat pirofosforilaza, IMP-GMP pirofosforilaza, HGPRTase, 6-hidroksipurin fosforiboziltransferaza, 6-merkaptopurin fosforiboziltransferaza, GMP pirofosforilaza, guanin-hipoksantin fosforiboziltransferaza, guanozin fosforiboziltransferaza, guanilat pirofosforilaza, guanilinska pirofosforilaza, inozinatna pirofosforilaza, inozin 5-fosfatna pirofosforilaza, inozinsko kiselinska pirofosforilaza, inozinska pirofosforilaza, 6-merkaptopurinska fosforiboziltransferaza, purin-6-tiolna fosforiboziltransferaza) je enzim sa sistematskim imenom IMP:difosfat fosfo-D-riboziltransferaza.[1][2][3][4] Ovaj enzim katalizuje sledeću hemijsku reakciju ...