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Protein kinase activity of Tel1p and Mec1p, two Saccharomyces cerevisiae proteins related to the human ATM protein kinase

Mallory, Julia C.; Petes, Thomas D.
Fonte: The National Academy of Sciences Publicador: The National Academy of Sciences
Tipo: text
Português
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The Saccharomyces cerevisiae proteins Tel1p and Mec1p are involved in telomere length regulation and cellular responses to DNA damage. The closest relative of these proteins is the human Ataxia Telangiectasia Mutated (ATM) protein, a wortmannin-sensitive protein kinase that primarily phosphorylates serines in an SQ motif. We constructed yeast strains containing functional epitope-tagged versions of Tel1p and Mec1p. We showed that immunoprecipitated Tel1p and Mec1p were capable of in vitro phosphorylation of the mammalian protein PHAS-I (Phosphorylated Heat and Acid Stable protein). These activities are sensitive to wortmannin. Tel1p phosphorylates serine in an SQ motif in PHAS-I. Mutations in the kinase domains of Tel1p and Mec1p result in loss of in vitro kinase activity and the in vivo phenotypes associated with the null tel1 and mec1 mutations.

Genomic Structure of the Salmonella enterica Serovar Typhimurium DT 64 Bacteriophage ST64T: Evidence for Modular Genetic Architecture

Mmolawa, Princess T.; Schmieger, Horst; Tucker, Carly P.; Heuzenroeder, Michael W.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /06/2003 Português
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The complete sequence of the double-stranded DNA genome of a serotype-converting temperate bacteriophage, ST64T, was determined. The 40,679-bp genomic sequence of ST64T has an overall GC content of 47.5% and was reminiscent of a number of lambdoid phages, in particular, P22. Inferred proteins of ST64T which exhibited a high degree of sequence similarity to P22 proteins (>90%) included the functional serotype conversion cassette, integrase, excisionase, Abc1, Abc2, early antitermination (gp24), NinD, NinH, NinZ, packaging (gp3 and gp2), head (with the exception of gp26, gp7, gp20, and gp16), and tail proteins. The putative immunity genes were highly related to those of Salmonella enterica serotype Typhimurium phage L, whereas the lysis genes were almost identical to those of S. enterica serovar Typhimurium PS3.

Fimbriation, capsulation, and iron-scavenging systems of Klebsiella strains associated with human urinary tract infection.

Tarkkanen, A M; Allen, B L; Williams, P H; Kauppi, M; Haahtela, K; Siitonen, A; Orskov, I; Orskov, F; Clegg, S; Korhonen, T K
Tipo: text
Publicado em /03/1992 Português
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Thirty-two strains of Klebsiella pneumoniae and seven strains of Klebsiella oxytoca isolated from urinary tract infections in elderly adults were analyzed for capsular antigens, iron-scavenging systems, and fimbriation. All strains were capsulated. Twenty-seven different K antigens were identified among the strains, with no particular antigen dominating. All strains produced the iron-scavenging system enterochelin as analyzed by bioassay and DNA hybridization. In contrast, the aerobactin iron-sequestering system was not detected in any of the strains. All strains caused hemagglutination of tannin-treated human erythrocytes and reacted with an anti-type 3 fimbriae antiserum as well as in DNA hybridization with a type 3 fimbria-specific probe, indicating that the Klebsiella strains possessed this fimbrial type. Possession of type 1 fimbriae was analyzed by agglutination tests and by hybridization with DNA probes from two distinct Klebsiella type 1 fimbria gene clusters. Phenotypic expression of the type 1 fimbriae was found in 29 of 32 K. pneumoniae strains, whereas 30 strains reacted with either of the two type 1 fimbrial cluster DNA probes. In K. oxytoca, however, only three of seven strains expressed type 1 fimbriae and reacted with the DNA probes. The type 3 fimbriae were found to bind to a fraction of epithelial cells exfoliated in normal human urine...

Comparison of different immunostaining techniques and monoclonal antibodies to the lower matrix phosphoprotein (pp65) for optimal quantitation of human cytomegalovirus antigenemia.

Gerna, G; Revello, M G; Percivalle, E; Morini, F
Tipo: text
Publicado em /05/1992 Português
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The main parameters of immunostaining techniques, i.e., the type of fixative, immunocytochemical reaction, and quality of monoclonal antibodies (MAbs), for quantitation of human cytomegalovirus (HCMV) antigenemia in peripheral blood polymorphonuclear leukocytes (currently performed by the indirect immunofluorescence or immunoperoxidase reaction by using MAbs to HCMV pp65) were investigated in order to optimize procedural steps and reagents. Significantly better results (in terms of the number of positive cells) were obtained on multiple cytospin preparations from heart transplant recipients with HCMV viremia when we used (i) formalin instead of methanol-acetone fixation and (ii) the indirect immunofluorescence reaction instead of the immunoperoxidase reaction, the avidin-biotin complex method, or the alkaline phosphatase antialkaline phosphatase procedure. In addition, comparison of the staining capabilities of three MAbs to pp65, which were developed in the laboratory and which were reactive to different epitopes of the protein, with a commercially available MAb (Clonab CMV) for determination of HCMV antigenemia showed that, while individual MAbs did not provide better results, the pool of MAbs detected a significantly higher number of positive peripheral blood polymorphonuclear leukocytes than Clonab CMV did. In addition...

A pancreas specificity results from the combination of polyomavirus and Moloney murine leukemia virus enhancer.

Rochford, R; Campbell, B A; Villarreal, L P
Tipo: text
Publicado em /01/1987 Português
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An infectious recombinant polyomavirus was constructed in which a regulatory region of its genome, the B enhancer region (nucleotides 5128-5265) has been replaced with the 72- or 73-base-pair repeat enhancer from the Moloney murine leukemia virus genome. We show that this recombinant polyomavirus displays a strong tissue specificity for the pancreas of mice. This organ was not permissive for either the parental polyomavirus, which is predominantly kidney and salivary gland specific, or the Moloney murine leukemia virus, which is lymphotropic. This result indicated that tissue specificity can be achieved by a combination of apparently modular elements. Some of the implications of a modular mechanism of tissue specificity are considered.

Protective Role of Smooth Lipopolysaccharide in the Serum Bactericidal Reaction

Reynolds, B. L.; Pruul, H.
Tipo: text
Publicado em /12/1971 Português
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The mechanism by which smooth lipopolysaccharide (LPS) protects Salmonella typhimurium C5 from the lethal action of specific antibody and complement has been investigated. Tris(hydroxymethyl)aminomethane (Tris) and ethylenediaminetetraacetate (EDTA), which sensitize S. typhimurium C5 to the bactericidal action of immune serum, were shown to cause appreciable structural modification of the smooth LPS associated with these cells. Mg2+ was shown to reverse the sensitization of C5 by Tris, but this divalent cation was unable to reverse the sensitizing effect of Tris plus EDTA, which, unlike Tris, caused relatively large amounts of O-antigenic components to be released from the C5 cell wall. The possibility that smooth LPS blocks the interaction of activated complement components with receptors on the cell wall is discussed.

THE OPTICAL CONVENTION

Tipo: text
Publicado em /06/1926 Português
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Submission of Microarray Data to Public Repositories

Ball, Catherine A; Brazma, Alvis; Causton, Helen; Chervitz, Steve; Edgar, Ron; Hingamp, Pascal; Matese, John C; Parkinson, Helen; Quackenbush, John; Ringwald, Martin; Sansone, Susanna-Assunta; Sherlock, Gavin; Spellman, Paul; Stoeckert, Chris; Tateno, Yos
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: text
Português
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The Microarray Gene Expression Data Society believe that the time is right for journals to require that microarray data be deposited in public repositories, as a condition for publication

Targeted disruption of the MYC antagonist MAD1 inhibits cell cycle exit during granulocyte differentiation.

Foley, K P; McArthur, G A; Quéva, C; Hurlin, P J; Soriano, P; Eisenman, R N
Tipo: text
Publicado em 02/02/1998 Português
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The switch from transcriptionally activating MYC-MAX to transcriptionally repressing MAD1-MAX protein heterodimers has been correlated with the initiation of terminal differentiation in many cell types. To investigate the function of MAD1-MAX dimers during differentiation, we disrupted the Mad1 gene by homologous recombination in mice. Analysis of hematopoietic differentiation in homozygous mutant animals revealed that cell cycle exit of granulocytic precursors was inhibited following the colony-forming cell stage, resulting in increased proliferation and delayed terminal differentiation of low proliferative potential cluster-forming cells. Surprisingly, the numbers of terminally differentiated bone marrow and peripheral blood granulocytes were essentially unchanged in Mad1 null mice. This imbalance between the frequencies of precursor and mature granulocytes was correlated with a compensatory decrease in granulocytic cluster-forming cell survival under apoptosis-inducing conditions. In addition, recovery of the peripheral granulocyte compartment following bone marrow ablation was significantly enhanced in Mad1 knockout mice. Two Mad1-related genes, Mxi1 and Mad3, were found to be expressed ectopically in adult spleen, indicating that functional redundancy and cross-regulation between MAD family members may allow for apparently normal differentiation in the absence of MAD1. These findings demonstrate that MAD1 regulates cell cycle withdrawal during a late stage of granulocyte differentiation...

Recruitment of the human TREX complex to mRNA during splicing

Masuda, Seiji; Das, Rita; Cheng, Hong; Hurt, Ed; Dorman, Nijsje; Reed, Robin
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: text
Publicado em 01/07/2005 Português
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In yeast, the TREX complex contains the THO transcription elongation complex, which functions in direct cotranscriptional recruitment of the mRNA export proteins Sub2 and Yra1 to nascent transcripts. Here we report the identification of the human THO complex and show that it associates with spliced mRNA, but not with unspliced pre-mRNA in vitro. Transcription is not required for this recruitment. We also show that the human THO complex colocalizes with splicing factors in nuclear speckle domains in vivo. Considering that splicing occurs cotranscriptionally in humans, our data indicate that recruitment of the human TREX complex to spliced mRNA is not directly coupled to transcription, but is instead coupled to transcription indirectly through splicing.

Liberation of amino acids in perennial rye grass during wilting

Kemble, A. R.; Macpherson, H. T.
Tipo: text
Publicado em /09/1954 Português
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Disorders of mythopoiesis.

Conacher, G N
Tipo: text
Publicado em /04/1998 Português
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Molecular Epidemiology of an Outbreak Caused by Methicillin-Resistant Staphylococcus aureus in a Health Care Ward and Associated Nursing Home

Kerttula, Anne-Marie; Lyytikäinen, Outi; Vuopio-Varkila, Jaana; Ibrahem, Salha; Agthe, Niina; Broas, Markku; Jägerroos, Henrik; Virolainen, Anni
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /12/2005 Português
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Our point-prevalence survey followed an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) in a long-term care facility and identified five MRSA strains, of which two possessed an outbreak genotype not encountered previously and three had another profile. All of them possessed SCCmec type V. Six methicillin-sensitive S. aureus strains were genotypically related to the epidemic strains.

Nutritional evaluation of caseins and whey proteins and their hydrolysates from Protamex*

Sindayikengera, Séverin; Xia, Wen-shui
Fonte: Zhejiang University Press Publicador: Zhejiang University Press
Tipo: text
Português
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Whey protein concentrate (WPC 80) and sodium caseinate were hydrolyzed by Protamex to 5%, 10%, 15%, and 20% degree of hydrolysis (DH). WPC 80, sodium caseinate and their hydrolysates were then analyzed, compared and evaluated for their nutritional qualities. Their chemical composition, protein solubility, amino acid composition, essential amino acid index (EAA index), biological value (BV), nutritional index (NI), chemical score, enzymic protein efficiency ratio (E-PER) and in vitro protein digestibility (IVPD) were determined. The results indicated that the enzymatic hydrolysis of WPC 80 and sodium caseinate by Protamex improved the solubility and IVPD of their hydrolysates. WPC 80, sodium caseinate and their hydrolysates were high-quality proteins and had a surplus of essential amino acids compared with the FAO/WHO/UNU (1985) reference standard. The nutritive value of WPC 80 and its hydrolysates was superior to that of sodium caseinate and its hydrolysates as indicated by some nutritional parameters such as the amino acid composition, chemical score, EAA index and predicted BV. However, the E-PER was lower for the WPC hydrolysates as compared to unhydrolyzed WPC 80 but sodium caseinate and its hydrolysates did not differ significantly. The nutritional qualities of WPC 80...

The Examination of Waters and Water Supplies

McCrady, M. H.
Tipo: text
Publicado em /05/1950 Português
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Diphtheria--the continuing hazard.

Bowler, I C; Mandal, B K; Schlecht, B; Riordan, T
Tipo: text
Publicado em /02/1988 Português
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An unimmunized schoolchild with no history of foreign travel developed severe diphtheria. Epidemiological investigations led to the discovery of a child in the same class with cutaneous diphtheria who had just returned from Bangladesh; this highlights the importance of swabbing all skin lesions acquired in endemic areas during any outbreak investigation.

Prevalence and associated factors of suicidal ideation among school-going adolescents in Guyana: results from a cross sectional study

Rudatsikira, Emmanuel; Muula, Adamson S; Siziya, Seter
Fonte: BioMed Central Publicador: BioMed Central
Tipo: text
Publicado em 23/08/2007 Português
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Epidemiology Section

Tipo: text
Publicado em 15/09/1945 Português
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SERUM ALBUMIN UPTAKE IN ISOLATED PERFUSED RENAL TUBULES : Quantitative and Electron Microscope Radioautographic Studies in Three Anatomical Segments of the Rabbit Nephron

Bourdeau, James E.; Carone, Frank A.; Ganote, Charles E.
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: text
Publicado em 01/08/1972 Português
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Proximal convoluted, proximal straight, and cortical collecting tubular segments isolated from rabbit kidney were perfused with I 125-labeled rabbit serum albumin (RSA-I 125) in ultrafiltrate of serum for up to 3 hr After perfusion, the segments were fixed with glutaraldehyde, embedded in Epon, and either counted with a gamma spectrometer to quantitate protein accumulation or analyzed by electron microscope radioautography to sequentially localize radioactivity Proximal convoluted and proximal straight segments accumulate RSA-I 125 nearly linearly as a function of time whereas cortical collecting segments do not accumulate measurable amounts of protein. The rate of accumulation of RSA-I 125 in the proximal convoluted tubule is 2 6 times as great as that in the proximal straight tubule. Electron microscope radioautography of the isolated proximal tubule demonstrated that RSA-I 125 is taken up via small apical vesicles and tubular invaginations, released into large cytoplasmic vacuoles, and finally concentrated in membrane-bounded structures, some of which are acid phosphatase positive These results show that albumin is absorbed by proximal tubules and may be degraded intracellularly within lysosomes. In addition, less radioactivity was located at all times over the lateral intercellular and basilar labyrinthine spaces...

William Joy

Tipo: text
Publicado em 03/07/1880 Português
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