The results of an investigation into the behavior of adhesively bonded doubler splices of two composite material sandwich panels are presented. The splices are studied from three approaches: analytical; numerical (finite elements); and experimental. Several parameters that characterize the splice are developed to determine their influence upon joint strength. These parameters are: doubler overlap length; core stiffness; laminate bending stiffness; the size of the gap between the spliced sandwich panels; and room and elevated temperatures. Similarities and contrasts between these splices and the physically similar single and double lap joints are discussed. The results of this investigation suggest several possible approaches to improving the strength of the sandwich splices.
BackgroundSubtle alternative splicing events involving tandem splice sites separated by a short (2-12 nucleotides) distance are frequent and evolutionarily widespread in eukaryotes,...Full Text Available
Na+ channels are often spliced but little is known about the functional consequences of splicing. We have been studying the regulation of Na+ current inactivation in an...Full Text Available
BackgroundAlternative splicing is an important mechanism mediating the diversified functions of genes in multicellular organisms, and such event occurs in around 40-60% of human...Full Text Available
Interactions between presynaptic and postsynaptic cellular adhesion molecules (CAMs) drive synapse maturation during development. These trans-synaptic interactions are regulated by alternative splicing...Full Text Available
The human immunodeficiency virus type 1 (HIV-1) packages its genomic RNA as a dimer of homologous RNA molecules that has to be selected among a multitude of cellular and viral RNAs. Interestingly, spliced...Full Text Available
Generation of replicative defective viruses is frequently observed during viral infections. We now report that encapsidation and reverse transcription of spliced viral RNA is an additional mechanism...Full Text Available
Metazoan development requires complex mechanisms to generate cells with diverse function. Alternative splicing of pre-mRNA not only expands proteomic diversity but also provides a means to regulate...Full Text Available
Indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) are tryptophan-degrading enzymes. Mammalian IDO expression is induced by cytokines and has antimicrobial and immunomodulatory effects. A major role of mammalian TDO is to supply nicotinamide adenine dinucleotide (NAD(+)). In fungi, the IDO homologue is thought to be expressed constitutively and supply NAD(+), as TDO is absent from their genomes. Here, we reveal the distribution of IDO genes among fungal species and characterize their enzymatic activity. The yeast, Saccharomyces cerevisiae has only one IDO gene, whereas the koji-mold, Aspergillus oryzae has two genes, IDO? and IDO?. The A. oryzae IDO? showed more similar enzymatic properties to those of S. cerevisiae IDO than IDO?, suggesting that the A. oryzae IDO? is a functional homologue of the S. cerevisiae IDO. From the IDO? gene, two isoforms, IDO? and IDO?(+) could be generated by alternative splicing. The latter ...
Although genetic engineering techniques for baker's yeast might improve the yeast's fermentation characteristics, the lack of scientific data on the survival of such strains in natural environments...Full Text Available
A mesophilic yeast, Candida utilis, and a psychrophilic yeast, Leucosporidium stokesii, were subjected to freeze-thaw cycling over the range 25 to -60 C. Viability...Full Text Available
We explored transcriptional responses of the fission yeast Schizosaccharomyces pombe to various environmental stresses. DNA microarrays were used to characterize changes in expression...Full Text Available
Budding yeasts are highly suitable for aging studies, because the number of bud scars (stage) proportionally correlates with age. Its maximum stages are known ...Full Text Available
In this study, we investigated on a systems level how complex protein interactions underlying cell polarity in yeast determine the dynamic association of proteins with the polar cortical domain (PCD)...Full Text Available
de Vito, Peter C. (Princeton University, Princeton, N.J.), and Jacques Dreyfuss. Metabolic regulation of adenosine triphosphate sulfurylase in yeast. J. Bacteriol. 88:1341–1348....Full Text Available
To define the import pathway for apoiso-1-cytochrome c in vivo, the coding region for bacterial chloramphenicol acetyltransferase (CAT) or yeast copper metallothionein (CuMT) was fused to the carboxy...Full Text Available
The electrokinetic patterns of four bacterial species (Bacillus subtilis, Bacillus megaterium, Pseudomonas aeruginosa, and Agrobacterium radiobacter), two yeasts (Saccharomyces cerevisiae and Candida...Full Text Available
We have identified five acyl coenzyme A (CoA) oxidase isozymes (Aox1 through Aox5) in the n-alkane-assimilating yeast Yarrowia lipolytica, encoded by the POX1...Full Text Available
BackgroundHistone post-translational modifications are critical for gene expression and cell viability. A broad spectrum of histone lysine residues have been identified in yeast...Full Text Available
Recent studies have indicated that the DNA replication machinery is coupled to silencing of mating-type loci in the budding yeast Saccharomyces cerevisiae, and a similar silencing mechanism...Full Text Available
Spontaneous and ultraviolet-induced changeabilities of wine yeasts from the killer state to sensitive one have been studied. Observed often spontaneous changes of killer and neutral phenotypes under laboratory store conditions as well as high mutation frequency of genetic elements responsible for the killer indication on ultraviolet irradiation testify that often encounterability in nature and in the production of sensitive yeasts is attributed to high frequency of mutation changes of the killer and neutral phenotypes to the sensitive state.
SR proteins are essential splicing factors whose function is controlled by multi-site phosphorylation of a C-terminal domain rich in arginine-serine repeats (RS domain). The protein kinase SRPK1 has been shown to polyphosphorylate the N-terminal portion of the RS domain (RS1) of the SR protein ASF/SF2, a modification that promotes nuclear entry of this splicing factor and engagement in splicing function. Later, dephosphorylation is required for maturation of the spliceosome and other RNA processing steps. While phosphates are attached to RS1 in a sequential manner by SRPK1, little is known about how they are removed. To investigate factors that control dephosphorylation, we monitored region-specific mapping of phosphorylation sites in ASF/SF2 as a function of the protein phosphatase PP1. W...
Splice products of the Kiss1 protein (kisspeptins) have been shown to be involved in a diverse range of functions, including puberty, metastasis and vasoconstriction in large human arteries. Circulating...Full Text Available
A splice assembly tool for assembling component parts of an electrical conductor while producing a splice connection between electrical cables therewith, comprises a first structural member adaptable for supporting force applying means thereon, said force applying means enabling a rotary force applied manually thereto to be converted to a longitudinal force for subsequent application against a first component part of said electrical connection, a second structural member adaptable for engaging a second component part in a manner to assist said first structural member in assembling the component parts relative to one another and transmission means for conveying said longitudinal force between said first and said second structural members, said first and said second structural members being coupled to one another by said transmission means, wherein at least one of said component parts comprises a tubular elastomeric sleeve and said force applying ...
The spliced alignment of expressed sequence data to genomic sequence has proven a key tool in the comprehensive annotation of genes in eukaryotic genomes. A novel algorithm was developed to assemble...Full Text Available
BackgroundMembers of the Sox gene family isolated from both vertebrates and invertebrates have been proved to participate in a wide variety of developmental processes, including...Full Text Available
PurposeTo detail the highly variable ocular phenotypes of a French family affected with an autosomal dominantly inherited vitreoretinopathy and to identify the disease gene.MethodsSixteen...Full Text Available
A number of preparations of residual non-living brewery yeast were examined for their ability to remove lead from solution. Those preparations included washed and un-washed intact yeast and washed and un-washed homogenates of the yeast cells. Using biosorption isotherm analysis it was found that the washed and un-washed preparations of intact, non-living yeast exhibited maximum biosorption capacities for lead of 127 and 99 mg/g dry weight biomass, respectively. The washed and un-washed cell homogenates exhibited maximum biosorption capacities of 38 and 139 mg lead/g dry weight biomass, respectively. Since it had previously been shown that these preparations of biomass were capable of removing uranium from solution by combined biosorption and precipitation processes, it was decided to examine removal of lead from solution using a form of equilibrium dialysis in which the biomass was retained within a ...
The role of intermediate products of dioxygen reduction in cytotoxic effects ascribed to oxygen molecules was studied in vivo using various yeast mutants with changed response to oxygen stress. It has been documented that superoxide radical exerts its deleterious effects on yeast cells directly and the role of other oxygen species derived from it is hardly detectable. Yeast Saccharomyces cerevisiae, however, cannot be considered as a typical eukaryotic organism due to its inability of synthesizing polyunsaturated fatty acids (pufa). These fatty acids are known as main target molecules during oxidative stress and their peroxidation leads to cytotoxic effects. As fatty acid content could be easily manipulated in yeast, this organism was used to evaluate the contribution of pufa peroxidation process to the cytotoxic effects of oxygen. Results obtained show, that yeast cells containing ...
The Sirtuins are a family of orthologues of yeast Sir2 found in a wide range of organisms from bacteria to man. They display a high degree of conservation between species, in both sequence and function,...Full Text Available
1. A high degree of homology in the positions of tyrosine residues in glyceraldehyde 3-phosphate dehydrogenase from lobster and pig muscle, and from yeast, prompted an examination of the reactivity...Full Text Available
We report that the fission yeast nucleoporin Nup124p is required for the nuclear import of both, retrotransposon Tf1-Gag as well as the retroviral HIV-1 Vpr. Failure to import Tf1-Gag into the nucleus...Full Text Available
We study the growth of colonies of the yeast Pichia membranaefaciens on agarose film. The growth conditions are controlled in a setup where nutrients are supplied through an agarose film suspended over a solution of nutrients. As the thickness of the agarose film is varied, the morphology of the front of the colony changes. The growth of the front is modeled by coupling it to a diffusive field of inhibitory metabolites. Qualitative agreement with experiments suggests that such a coupling is responsible for the observed instability of the front.
The yeast phosphatidylinositol transfer protein (Sec14p) is required for biogenesis of Golgi-derived transport vesicles and cell viability, and this essential Sec14p requirement is abrogated by inactivation...Full Text Available
Toxin-secreting “killer” yeasts were initially identified >40 years ago in Saccharomyces cerevisiae strains infected with a double-stranded RNA “killer”...Full Text Available
Fission yeast S. pombe is assumed to be a good model for cloning of human DNA repair genes, because human gene is normally expressed in S. pombe and has a very similar protein sequence to yeast protein. We have tried to elucidate the DNA repair mechanisms of S. pombe as a model system for those of mammals. (J.P.N.)
Yeast arginyl-tRNA synthetase recognizes the non-modified wild-type transcripts derived from both yeast tRNA(Arg) and tRNA(Asp) with equal efficiency. It discriminates its cognate natural substrate,...Full Text Available
Histone-beta-galactosidase protein fusions were used to identify the domain of yeast histone 2B, which targets this protein to the nucleus. Amino acids 28 to 33 in H2B were required for nuclear localization...Full Text Available
Transcription activation of sulfur metabolism in yeast is dependent on two DNA binding factors, the centromere binding factor 1 (Cbf1) and Met4. While the role of Met4 was clearly established by showing...Full Text Available
Suicide substrate β, γ-bidentate Rh(III)ATP (RhATP) was used to map the metal ion-binding site in yeast phosphoglycerate kinase (PGK). Cleavage of the RhATP-inactivated enzyme with...Full Text Available
Gastrin and its carboxyl-terminal homolog cholecystokinin (CCK) exert a variety of biological actions in the brain and gastrointestinal tract that are mediated in part through one or more G protein-coupled...Full Text Available
We have isolated and sequenced cDNA clones encoding the human U1-70K snRNP protein, and have mapped this locus (U1AP1) to human chromosome 19. The gene produces two size classes of RNA, a major 1.7-kb...Full Text Available
Inhibition of large conductance calcium-activated potassium (BKCa) channels mediates, in part, oxygen sensing by carotid body type I cells. However, BKCa channels remain active...Full Text Available
We have identified another Drosophila GTP-binding protein (G protein) alpha subunit, dGq alpha-3. Transcripts encoding dGq alpha-3 are derived from alternative splicing of the dGq alpha locus previously...Full Text Available
Although human T-cell lymphotropic virus type I (HTLV-I) is the etiologic agent of adult T-cell leukemia/lymphoma (ATL), the role of viral gene expression in the progression to and maintenance of the...Full Text Available
Severe collapse wrinkles and circumferential creases were discovered in the cellulose paper insulating tapes of a newly installed IIPFF pipe-type cable during splicing and terminating. An evaluation program was developed to assess the electrical and mechanical integrity of the cable having wrinkled and creased insulating tapes. The test results indicated that the cable would perform satisfactorily in service.
The Epstein-Barr virus nuclear antigen (EBNA I) present in latently infected cells is encoded in a 2-kilobase exon contained in the BamHI K viral genomic fragment. This exon is, however, found within...Full Text Available
The transcriptional co-activator PGC-1α regulates functional plasticity in adipose tissue by linking sympathetic input to the transcriptional program of adaptive thermogenesis. We report here...Full Text Available
To understand how DEXD/H-box proteins recognize and interact with their cellular substrates, we have been studying Prp28p, a DEXD/H-box splicing factor required for switching the U1 snRNP with the U6...Full Text Available
Over the decades, basic research in life sciences has profited greatly from the study of the small unicellular fungal species Saccharomyces cerevisiae. This yeast turned out to be key for the identification and understanding of molecular mechanisms that underlay the basic functions of all eukaryotic cells. These include, but are not limited to, the regulatory mechanisms behind cellular reproduction (cell cycle control), cellular morphogenesis (cell polarity, cytoskeleton and membrane trafficking) and the management of cellular information (chromosome biology, transcription and translation). Rapid access to genomic information of many yeast species, combined with bioinformatics analyses, provide information on the evolutionary history of yeasts and the molecular ancestry of their constituen...
Eight culture-collection yeast strains of various species and five newly isolated stains were tested for both growth in olive oil extraction effluents and fermentation of the sugars in the same media. The culture-collection yeast strains did not grow in an effluent containing 2.86% sugar (w/v), 8 g/litre phenolic substances, 4.58 g/litre titratable acidity and pH 4.96, whereas the newly isolated strains of Torulopsis sp. MK-1, Saccharomyces norbensis MC-1, S. oleaceus MC-2 and S. oleaginosus grew well and fermented the sugars. In the medium mentioned above, they produced alcohol in amounts of 1.63 to 1.38%, respectively. None of the yeasts grew in an olive oil extraction effluent vacuum-concentrated to over 13-14% of dry matter. The strain of T. sp. MK-1 showed a higher stability.
The Ty transposable elements of Saccharomyces cerevisiae form a heterogeneous family within which two broad structural classes (I and II) exist. The two classes differ by two large substitutions and...Full Text Available
The mini-chromosome maintenance proteins Mcm2–7 are essential for DNA replication. They are loaded onto replication origins during G1 phase of the cell cycle to form a pre-replication complex...Full Text Available
Tropomyosin (Tm) is a conserved dimeric coiled-coil protein, which forms polymers that curl around actin filaments in order to regulate actomyosin function. Acetylation of the Tm N-terminal...Full Text Available
DNA methylation of cytosine residues is a widespread phenomenon and has been implicated in a number of biological processes in both prokaryotes and eukaryotes. This methylation occurs at the 5-position...Full Text Available
The exocyst is an evolutionarily conserved octameric complex involved in polarized exocytosis from yeast to humans. The Sec3 subunit of the exocyst acts as a spatial landmark for exocytosis through...Full Text Available
This annual review focuses on invertebrate model organisms, which continue to yield fundamental new insights into mechanisms of aging. This year, the budding yeast has been used to understand how asymmetrical...Full Text Available
Yeast Sir2 deacetylase is a component of the silent information regulator (SIR) complex encompassing Sir2/Sir3/Sir4. Sir2 is recruited to telomeres through Rap1, and this complex spreads into subtelomeric...Full Text Available
Eukaryotic cells can massively transport their own cytoplasmic contents into a lytic compartment, the vacuole/lysosome, for recycling through a conserved system called autophagy. The key process in...Full Text Available
BackgroundThe expression of human virus surface proteins, as well as other mammalian glycoproteins, is much more efficient in cells of higher eukaryotes rather than yeasts. The limitations...Full Text Available
Mutant strains of the yeast Saccharomyces cerevisiae which lack functional Cu,Zn superoxide dismutase (SOD-1) do not grow aerobically unless supplemented with methionine. The molecular basis of this...Full Text Available
The number of nuclear pore complexes (NPCs) in individual nuclei of the yeast Saccharomyces cerevisiae was determined by computer-aided reconstruction of entire nuclei from electron...Full Text Available
To gain insight into the process of mitochondrial transmission in yeast, we directly labeled mitochondrial proteins and mitochondrial DNA (mtDNA) and observed their fate after the fusion of two cells....Full Text Available
Sirtuins are highly conserved NAD+-dependent protein deacetylases and/or ADP-ribosyltransferases that can extend the lifespan of several lower model organisms including yeast, worms and flies....Full Text Available
SummaryThe general transcription factor TFIID is a large multi-subunit complex required for the transcription of most protein-encoding genes by RNA polymerase II. Taking advantage...Full Text Available
Three Legionella-like organisms were isolated from water from the cooling towers of two Australian institutions. The strains grew on buffered charcoal-yeast extract (BCYE) agar but not on BCYE agar...Full Text Available
Cdc13 is a single stranded telomere binding protein that specifically localizes to the telomere ends of budding yeasts and is essential for cell viability. It caps the ends of chromosomes thus preventing...Full Text Available
Baker's yeast (Saccharomyces cerevisiae) has been genetically engineered to ferment the pentose sugar xylose present in lignocellulose biomass. One of the reactions controlling the...Full Text Available
The beneficial effect of improving yeast redox response by increasing thioredoxin levels has been shown. Decreased lipid and protein oxidation is reflected in an increased biomass yield. In addition,...Full Text Available
Calorie restriction (CR) induces a metabolic shift towards mitochondrial respiration; however, molecular mechanisms underlying CR remain unclear. Recent studies suggest that CR-induced mitochondrial...Full Text Available
Cryptococcus neoformans is a pathogenic yeast that often causes devastating meningoencephalitis in immunocompromised individuals. We have previously identified the C. neoformans...Full Text Available
A fuzzy-decision-making procedure is applied to find the optimal feed policy of a fed-batch fermentation process for fuel ethanol production using a genetically engineered Saccharomyces yeast 1400 (pLNH33). The policy consisted of feed flow rate, feed concentration, and fermentation time. The recombinant yeast 1400 (pLNH33) can utilize glucose and xylose simultaneously to produce ethanol. However, the parent yeast utilizes glucose only. A partially selective model is used to describe the kinetic behavior of the process. In this study, this partially selective fermentation process is formulated as a general multiple-objective optimal control problem. By using an assigned membership function for each of the objectives, the general multiple-objective optimization problem can be converted into a maximizing decision problem. In order to obtain a global solution, a hybrid method of differential evolution is introduced to solve ...
It was found that neither the enzymes of the grapes nor those of wine yeast Saccharomyces ellipsoideus strain 223 attacked the higher polysaccharides present in corn syrups. The alcohol...Full Text Available
Spinocerebellar ataxia 10 (SCA10) is an autosomal dominant disease caused by large-scale expansions of the (ATTCT)n repeat within an intron of the human ATXN10 gene. In contrast...Full Text Available
The delivery of proteins and organelles to the vacuole by autophagy involves membrane rearrangements that result in the formation of large vesicles called autophagosomes. The mechanism underlying autophagosome...Full Text Available
The programming of cellular networks to achieve new biological functions depends on the development of genetic tools that link the presence of a molecular signal to gene-regulatory activity. Recently,...Full Text Available
The opportunistic pathogenic yeast Candida albicans exhibits growth phase-dependent changes in cell surface hydrophobicity, which has been correlated with adhesion to host tissues....Full Text Available
A high-throughput assay for enzyme activity has been developed that is reaction independent. In this assay, a small-molecule yeast three-hybrid system is used to link enzyme catalysis to transcription...Full Text Available
Several independent studies of bacterial degradation of nitrate ester explosives have demonstrated the involvement of flavin-dependent oxidoreductases related to the old yellow enzyme (OYE) of yeast....Full Text Available
DNA replication programs have been studied extensively in yeast and animal systems, where they have been shown to correlate with gene expression and certain epigenetic modifications. Despite the conservation...Full Text Available
BackgroundThe production of high yields of recombinant proteins is an enduring bottleneck in the post-genomic sciences that has yet to be addressed in a truly rational manner. Typically...Full Text Available
Botulism is caused by the botulinum neurotoxins (BoNTs), the most poisonous substance known. Because of the high potency of BoNT, development of diagnostic and therapeutic antibodies for botulism requires...Full Text Available
In the yeast Saccharomyces cerevisiae, a and α mating-type information is stored in transcriptionally silenced cassettes called HML and HMR....Full Text Available
Hyperphosphorylated and aggregated human protein tau constitutes a hallmark of a multitude of neurodegenerative diseases called tauopathies, exemplified by Alzheimer's disease. In spite of an enormous amount of research performed on tau biology, several crucial questions concerning the mechanisms of tau toxicity remain unanswered. In this paper we will highlight some of the processes involved in tau biology and pathology, focusing on tau phosphorylation and the interplay with oxidative stress. In addition, we will introduce the development of a human tau-expressing yeast model, and discuss some crucial results obtained in this model, highlighting its potential in the elucidation of cellular processes leading to tau toxicity.
Cultured fish and human cells have been used as bioassay systems for the evaluation of the toxicity of aquatic pollutants. Numerous assays using bacteria and yeast have also been used for such purposes. The authors report the toxicity of aquatic pollutants (Cd, Hg, and Ni), using cell culture systems and the yeast Saccharomyces cervisiae test. Cd, Hg, and Ni were chosen as model compounds of pollutants because the related toxicity is now fairly well established.
The principle aim of the program was to produce a novel, non-leaching antimicrobial surface for commercial development and future use in the liquid food packaging industry. Antimicrobial surfaces which exist presently have been produced to combat the growth of prokaryotic organisms and usually function as slow release systems. A system which could inhibit eukaryotic growth without contaminating the surrounding 'environment' with the inhibitor was considered of great commercial importance. The remit of this study was concerned with creating a surface which could control the growth of eukaryotic organisms found in fruit juice with particular interest in the yeast, Saccharomyces cerevisiae. Putative antimicrobial surfaces were created by the chemical modification of the test substrate polymers; nylon and ethylvinyl alcohol (EVOH). Surfaces were chemically modified by the covalent coupling of antimicrobial agents known to be active against the ...
Studies were conducted to examine the pressure on fluid-filled cables of electric power transmission networks in the event of an oil leak. Transition splices between paper-insulated oil-impregnated cable systems (PILC) and solid dielectric cable is difficult to perform. A proper PILC is composed of a means to contain oil within the cable structure and to keep moisture out. A failure of the cable joint could occur if an oil leak dries out the paper. Since oil pressure in most PILC cables is high, strong mechanical means must be devised to contain the oil within the cable. Resin systems, heat shrink systems and wiped lead sleeves to reseal the PILC cable over the splice, are among the methods used to stop an oil leak. A system has been designed using an EPDM tube contained under mechanical pressure; it has proven to be effective over a wide range of pressure conditions. Test results utilizing this system were presented. 1 ref., 1 tab., 4 figs.
A Digital X-ray imaging system using Compton backscattering has been developed to obtain a cross-sectional profile and mass loss of corroded lap-splices of aging aircraft from density variation. A slit-type camera was designed to focus on a small scattering volume inside the material, from which the backscattered photons are collected by a collimated scintillator detector for interpretation of material characteristics. The cross section of the lap-joint is scanned by moving the scattering volume through the thickness direction of the specimen. The mass loss of each layer has been estimated from a Compton backscatter A-scan to obtain the thickness of each layer including the aluminum sheet, the corrosion layer and the sealant. Quantitative information such as location and width of planar corrosion in the lap splices of fuselages is obtained by deconvolution using a nonlinear least-square error minimization method(BFGS method): A simple ...
Yeast artificial chromosome (YAC) libraries have been difficult to construct with average insert sizes >400 kilobase pairs when DNA is size-fractionated in low-melting-point agarose. By using yeast chromosomes in mock cloning experiments, the authors found that polyamines should be present whenever agarose containing high molecular weight DNA is melted to protect DNA from degradation. By incorporating polyamines during the cloning procedure, they constructed YAC libraries from mouse and human DNA with average insert sizes of 700 and 620 kilobase pairs, respectively. Several genome equivalents of these YAC libraries were replicated onto the surface of many duplicate agar plates using a 40,000 multipin transfer device. High-density filter replicas were screened by hybridization, and 70 mouse YAC clones from 31 loci and 132 human YAC clones from 49 loci were isolated.
Homology analyses of the protein sequences of chicken liver and rat mammary gland fatty acid synthases were carried out. The amino acid sequences of the chicken and rat enzymes are 67% identical. If conservative substitutions are allowed, 78% of the amino acids are matched. A region of low homologies exists between the functional domains, in particular around amino acid residues 1059-1264 of the chicken enzyme. Homologies between the active sites of chicken and rat and of chicken and yeast enzymes have been analyzed by an alignment method. A high degree of homology exists between the active sites of the chicken and rat enzymes. However, the chicken and yeast enzymes show a lower degree of homology. The DADPH-binding dinucleotide folds of the {beta}-ketoacyl reductase and the enoyl reductase sites were identified by comparison with a known consensus sequence for the DADP- and FAD-binding dinucleotide folds. The active sites of all of the enzymes ...
In response to a heat shock, the yeast Saccharomyces cerevisiae undergoes a large increase in its resistance to heat and, by the induction of its recombinational DNA repair capacity, a corresponding increase in resistance to radiation. Yeast which lack mitochondrial DNA, mitochondria-controlled protein synthetic apparatus, aerobic respiration, and electron transport (rho/sup 0/ strain) were used to assess the role of O/sub 2/, mitochondria, and oxidative processes controlled by mitochondria in the induction of these resistances. We have found that rho/sup 0/ yeast grown and heat shocked in either the presence or absence of O/sub 2/ are capable of developing both radiation and heat resistance. We conclude that neither the stress signal nor its cellular consequences of induced heat and radiation resistance are directly dependent on O/sub 2/, mitochondrial DNA, or mitochondria-controlled protein synthetic or oxidative ...
Whilst unwashed preparations of biomass from a local brewery had an apparent maximum biosorption capacity for uranium of 360 mg/g (dry weight biomass) washing reduced this maximum to 150 mg/g. Homogenization of both biomass preparations and recovery of cellular debris had no significant effect on the maximum biosorption capacities although at lower equilibrium concentrations of uranium differences in the biosorption capacities were detected. When unwashed biomass was retained by a semi-permeable membrane 40% of uranium used in the experiments precipitated outside that membrane. Therefore a significant proportion of the uranium removed from solution, and previously attributed to biosorption by the yeast biomass, resulted from precipitation brought about by interaction with low molecular weight components loosely associated with the biomass. (Author).
Pectin rich cold stored spoiled fruits, vegetables and cold soils were screened and different pectinolytic isolates were obtained by enrichment culturing and ruthenium red plate assay. Among the primary isolates 10-15% were yeast isolates. Six isolates with higher zones of pectin hydrolysis were selected and tested for polygalacturonase (PGU) production at room temperature (25 degrees C) and at 5 degrees C. One isolate identified as Saccharomyces sp. with highest polygalacturonase activity at 5 degrees C was used for enzyme production using raw fruit pectins as substrates. The isolate was identified by preliminary cultural, morphological and sugar fermentation tests. PGU production was high in raw pectin substrates like orange peel (21 U/ml), apple peel (20 U/ml ), mango peel (19 U/ml), ...
Abstract Microbiological quality and biophenol content evolution was studied in minimally processed Thassos cv table olives by hot air dehydration under mild conditions (40C, 24-h, aw-=-0.893) and storage under characteristic packaging conditions (vacuum, 100% N2 and air) at 4 and 20C over a period of 180 days. No salt was used in the production line or packaging. The undesirable microorganisms (Enterobacteriaceae, Staphylococcus aureus, Bacillus, Clostridium) were undetectable until the end of the storage period. Also, modified atmospheres prevented fungal growth at both temperatures apart from the samples stored in air, in which Penicillium and Aspergillus spp. were identified. At 20C, a coexistence of mesophilic bacteria and yeasts occurred. At 4C, yeasts were the predominant microflora...
A 65-yr-old female developed cough, fever and dyspnoea following repeated exposure to a home ultrasonic humidifier. High-resolution computed tomography showed ground-glass opacity in both lung fields. Arterial blood gas analysis gave an oxygen tension of 8.38 kPa (63 Torr). Pulmonary function testing revealed restrictive ventilatory impairment with a reduction in the diffusing capacity. The diagnosis of extrinsic allergic alveolitis (EAA) was confirmed by radiographic findings, pathological evidence of alveolitis and reproductive development by a provocation test to the humidifier water. The yeast Debaryomyces Hansenii was the only microorganism cultured from the water of the humidifier. The double diffusion precipitating test and lymphocyte proliferative response was positive for an extract of D. Hansenii, providing evidence to incriminate this fungus. This is the first described case of EAA caused by D. Hansenii. PMID:12449192
The effects of dietary plant and yeast cerebroside (glucosylceramide), a major sphingolipid in plants and yeast, on atopic dermatitis (AD) like symptoms were investigated in a mouse model. After 7 wk of feeding with a diet containing maize glucosylceramide, plasma IgE levels became significantly lower and in contrast, the levels of interleukin (IL)-12, which induces cellular immunity, became significantly higher in the AD mice than in the controls. However, the sphingolipid constituents of the skin fraction in the maize glucosylceramide fed group did not contain sphingoid bases of plant origin, such as 8-unsaturated sphingoid bases. The results of the present study indicated that dietary plant glucosylceramide prevented AD-like symptoms in AD model mice via regulation of Th1/Th2 balance. P...
Ribosomal protein L1 from Saccharomyces cerevisiae binds 5S rRNA and can be released from intact 60S ribosomal subunits as an L1-5S ribonucleoprotein (RNP) particle. To understand the nature of the...Full Text Available
Because of variations in tRNA sequences in evolution, tRNA synthetases either do not acylate their cognate tRNAs from other organisms or execute misacylations which can be deleterious in vivo. We report...Full Text Available
Lethal alleles of the Drosophila k43 gene result in small or missing imaginal discs, greatly reduced mitotic index, and fragmented and abnormally condensed chromosomes. A female-sterile...Full Text Available
In order to study the intragenic profiles of active transcription, we determined the relative levels of active RNA polymerase II present at the 3′- and 5′-ends of 261 yeast genes by...Full Text Available
The Sin3-histone deacetylase (HDAC) corepressor complex is conserved from yeast to humans. Mammals possess two highly related Sin3 proteins, mSin3A and mSin3B, which serve as scaffolds tethering HDAC...Full Text Available
The histone chaperone Asf1 and the chromatin remodeler SWI/SNF have been separately implicated in derepression of the DNA damage response (DDR) genes in yeast cells treated with genotoxins that cause...Full Text Available
A refined map for the linear arrangement of histones along DNA in nucleosomal core particles has been determined by DNA-protein crosslinking. On one strand of 145-bp core DNA, histones are aligned in...Full Text Available
BackgroundThe large sensitivity, high reproducibility and essentially unlimited dynamic range of real-time PCR to measure gene expression in complex samples provides the opportunity...Full Text Available
Chapter 5, describes some of the most important molecular methods used in the study of chromosome structure and function. The methods discussed include fragmentation of DNA, cloning, flow cytometry and chromosome sorting, is situ hybridization, polymerase chain reaction (PCR), and yeast artificial chromosomes (YACs). 18 refs., 3 figs., 1 tab.
DescriptionThis project is part of the BBSRCs special initiative on plant and microbial metabolomics. The project will primarily focus on the trichothecene mycotoxin producing Ascomycete fungus Fusarium graminearum (Fg) which causes ear blight disease of small grain cereals. The project aims to explore the metabolome of various wild-type and single gene deletion Fg strains and to compare some of these with the identical gene mutation in the budding yeast, S. cerevisiae (Sc) and the saprophytic filamentous [continued...
Procedures are described for the use of synthetic oligonucleotides for Southern blot experiments and gene bank screening, and the effect of various mismatches on the efficiency of hybridization is demonstrated. The following topics are discussed: sensitivity vs. specificity, hybridization of a 12-mer to the lambda endolysin gene; hybridization of oligonucleotide probes to the E. coli lac operator; hybridization of synthetic probes to the CYC1 gene of yeast; and cloning eucaryotic genes. (HLW)
The N1-methyl-Adenosine (m1A58) modification at the conserved nucleotide 58 in the TΨC loop is present in most eukaryotic tRNAs. In yeast, m1A58 modification...Full Text Available
Acyl-CoA:diacylglycerol acyltransferase (EC 2.3.1.20) is a membrane protein present mainly in the endoplasmic reticulum. It catalyzes the final and committed step in the biosynthesis of triacylglycerol,...Full Text Available
Compared to yeast esterase, fungal cutinase degraded butyl benzyl phthalate (BBP) far more efficiently; i.e., almost 60% of the BBP disappeared within 7.5 h. Also, the final chemical composition significantly...Full Text Available
Current investigations into the biological solubilization of coal with microorganisms focus on the production of solubilizing activity in fungi. Test organisms for this work include a species of the yeast Candida previously isolated from a lignite outcrop, and P. chrysosporium, a filamentous higher fungus which has played a major role in lignin biodegradation research. The studies described are primarily exploratory in nature, and are fundamental to the design of more sophisticated inquiries into the physiology of fungal coal solubilization.
Temperature-sensitive mutants defective in 60S ribosomal subunit protein L16 of Saccharomyces cerevisiae were isolated through hydroxylamine mutagenesis of the RPL16B gene and plasmid shuffling. Two...Full Text Available
We have determined the actual RNA sequence of four mitochondrial genes: pcf, nad3, rps12, and coxII. Because plant mitochondrial proteins cannot be predicted from DNA sequences, the actual primary structures of the encoded proteins were unknown. We have gained information concerning the process of RNA editing. Editing can occur before splicing. Our data is consistent with the hypothesis that RNA editing is not simultaneous with transcription. Unlike other systems, the process of editing in plant does not exhibit a discernable direction. As a result of our RNA editing studies, we have produced a number of clones of the proper coding regions tube used for incorporating these mitochondrial genes into the nucleus. 6 refs., 4 figs.
SummaryExperimental evidence has demonstrated the importance of FGF signalling in morphogenesis of the mandibular processes. FGFs transmit their signals through four tyrosine kinase transmembrane receptors (FGFRs). Alternative splicing in FGFRs including FGFR2 generates different isoforms that exhibit different ligand-specificities, exclusive tissue distributions and specific biological functions. Despite extensive information regarding the isoform-specific patterns of expression Fgfr2c and Fgfr2b during morphogenesis of many organs, a comparative analysis of these specific isoforms in the chick mandible has not been reported. To better understand the function of FGFR2 in mandibular morphogenesis, we have analysed the expression Fgfr2b, Fgfr2c and their putative ligands Fgf10 and Fgf9, in ...
Retroelements constitute a large part of the human genome. These sequences are mostly silenced in normal cells, but genome-wide DNA hypomethylation in cancers might lead to their re-expression. Whether this re-expression really occurs in human cancers is largely unkown. We therefore investigated expression and DNA methylation of several classes of retroelements in human prostate cancer tissues and cell lines by quantitative reverse transcription-polymerase chain reaction and pyrosequencing, respectively. The most striking finding was strong and generalized increased expression of the HERV-K_22q11.23 provirus in cancers, including de novo expression of a spliced accessory Np9 transcript in some tumors. In parallel, DNA methylation in the long terminal repeat (LTR) decreased. Conversely, HER...
Fibroblast growth factor (FGF) signaling has been shown to regulate lung epithelial development but its influence on mesenchymal differentiation has been poorly investigated. To study the role of mesenchymal FGF signaling in the differentiation of the mesenchyme and its impact on epithelial morphogenesis, we took advantage of Fgfr2c+/? mice, which due to a splicing switch express Fgfr2b in mesenchymal tissues and manifest Apert syndrome-like phenotypes. Using a set of in vivo and in vitro studies, we show that an autocrine FGF10?FGFR2b signaling loop is established in the mutant lung mesenchyme, which has several consequences. It prevents the entry of the smooth muscle progenitors into the smooth muscle cell (SMC) lineage and results in reduced fibronectin and elastin deposition. Levels of...
The Lesch-Nyhan (LN) syndrome is a severe X chromosome-linked disease that results from a deficiency of the purine salvage enzyme hypoxanthine phosphoribosyltransferase (HPRT). The mutations leading to the disease are heterogeneous and frequently arise as de novo events. The authors have identified nucleotide alterations in 15 independently arising HPRT-deficiency cases by direct DNA sequencing of in vitro amplified HPRT cDNA. They also demonstrate that the direct DNA sequence analysis can be automated, further simplifying the detection of new mutations at this locus. The mutations include DNA base substitutions, small DNA deletions, a single DNA base insertion, and errors in RNA splicing. The application of these procedures allows DNA diagnosis and carrier identification by the direct detection of the mutant alleles within individual families affected by LN.
Glial fibrillary acidic protein (GFAP) is the main intermediate filament protein in mature astrocytes, but also an important component of the cytoskeleton in astrocytes during development. Major recent developments in astrocyte biology and the discovery of novel intermediate filament functions enticed the interest in the function of GFAP. The discovery of various GFAP splice variants gave an additional boost to explore this protein in more detail.The structural role of GFAP in astrocytes has been widely accepted for a long time, but over the years, GFAP has been shown to be involved in astrocyte functions, which are important during regeneration, synaptic plasticity and reactive gliosis. Moreover, different subpopulations of astrocytes have been identified, which are likely to have distinc...
A clone encoding a human D{sub 2} dopamine receptor was isolated from a pituitary cDNA library and sequenced. The deduced protein sequence is 96% identical with that of the cloned rat receptor with one major difference: the human receptor contains an additional 29 amino acids in its putative third cytoplasmic loop. Southern blotting demonstrated the presence of only one human D{sub 2} receptor gene. Two overlapping phage containing the gene were isolated and characterized. DNA sequence analysis of these clones showed that the coding sequence is interrupted by six introns and that the additional amino acids present in the human pituitary receptor are encoded by a single exon of 87 base pairs. The involvement of this sequence in alternative splicing and its biological significance are discussed.
Investigations into sexual differentiation and pheromone response in the fission yeast Schizosaccharomyces pombe are complicated by the need to first starve the cells of nitrogen. Most mating-related experiments are therefore performed on non-dividing cells. Here we overcome this problem by using two mutants that bypass the nutritional requirements and respond to the M-factor mating pheromone in rich medium. The first mutant lacks the cyr1 gene which encodes adenylate cyclase and these cells contain no measurable amounts of cAMP. When M-factor is added to a growing h+ cyr1- strain it causes a transient G1 arrest of cell division, transcription of mat1-Pm, and elongation of the cells to form shmoos. The second mutant contains the temperature-sensitive pat1-114 allele. At 30 degrees C this mutant was previously shown not only to bypass the nutritional signal but also to stop growing in a state derepressed for pheromone-controlled functions. We now report that an h+ ...
Ethidium bromide (EB) and ultraviolet light (UV) in combination are known to produce a synergistic induction of 'petite' mutants in yeast. Two other agents were combined with EB, 3-Carbethoxypsoralene (3 CPs) activated by 365 nm light or #gamma# rays. EB in combination with 3 CPs also resulted in an enhanced production of 'petite' mutants. After the photoaddition of 3 CPs in exponential phase cells, recovery of the 'petite' mutation during dark liquid holding was inhibited by the presence of EB producing an enhanced number of 'petite' mutants. The behavior of mitochondrial antibiotic resistance markers after individual and combined treatments with EB and 3 CPs indicates a random loss of markers after EB and a preferential loss of a certain region for the 3 CPs photoaddition. The combination of the two agents leads to an additivity of total drug marker losses rather than a synergistic loss. The combination of EB with #gamma# rays produced no enhancement in 'petite' ...
This paper presents a summary of the first phase of the EPA project, which encompasses surveys of residues from industrial sources in Alexandria. Studies to date indicate that wastes from various industries can be recovered economically. Wastes such as tin cans, glass, wastepaper, and food residues from processing of fruits, starch, and beer are examples of reusable industrial wastes in Egypt. The results of experimental studies for reuse of residues from oil refining, starch and yeast processing, and steel pickling are presented. Spent clay from edible oil refining is currently discarded, causing both handling and disposal problems. This clay contains as much as 40% oil; 90% can be recovered by extraction. The recovered oil can be successfully used in soap production, and the spent clay can be reused in oil bleaching. Other examples include starch and yeast wastes, which can be used for animal feed, and spent pickling liquor, which can be used ...
Papers in this book illustrate the utility of mineral biotechnology with respect to biobeneficiation, bioleaching, bioremediation and biomineralization. Papers of particular interest to the coal industry include: depression of pyrite flotation by yeast and bacteris (S.K. Kawatra and T.C. Eisele); desulfurization of coal by microbial flotation in a semicontinuous system (T. Nagaoka and others); biochemical removal of HAP precursors from coal - INEEL slurry column testing (K.S. Noah and G.J. Olson); microorganisms, biotechnology and acid rock drainage - emphasis on passive-biological control and treatment methods (N. Kuyucak); and utility of bioreagents in mineral processing (P. Somasundaran and others).
The biodegradation of ring-/sup 14/C- and methyl-/sup 14/C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO/sub 2/. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.
The biodegradation of ring-"1"4C- and methyl-"1"4C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO_2. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.
Scientists of the Institute of Wood Chemistry of the Latvian Academy of Sciences have developed two highly efficient processes for producing furfural, a feedstock for varnishes, synthetic resins and plastics. It is made of production wastes, including branches and small-dimension timber. By one process, the raw material is chipped, treated first with diluted sulphuric acid and then with steam heated to 250 degrees C. The other uses concentrated sulphuric acid as a catalyst. Besides furfural, this process also yields sugar solutions used in alcohol and nutrient yeast production.
Glabridin, an active constituent of Glycyrrhiza glabra roots, was found to be active against both yeast and filamentous fungi. Glabridin also showed resistance modifying activity against drug resistant mutants of Candida albicans at a minimum inhibitory concentration of 31.25-250 g/mL. Although the compound was reported earlier to be active against Candida albicans, but this is the first report of its activity against drug resistant mutants. Copyright Copyright 2009 John Wiley & Sons, Ltd.
Piper regnellii (Miq.) C. DC. var. pallescens (C. DC.) Yunck (Piperaceae) is a medicinal plant traditionally used in Brazil to treat infectious diseases. The extracts obtained from the leaves of P. regnellii were investigated for their antifungal activities against the yeasts Candida albicans, C. krusei, C. parapsilosis, and C. tropicalis. The EtOAc extract presented gnificant activity against Candida albicans with MIC at 125 {mu}g mL{sup -1}, and a moderate activity against both C. krusei and C. parapsilosis with MIC at 500 {mu}g mL{sup -1}. Candida tropicalis was not inhibited by this extract at concentrations as high as 1000 {mu}g mL{sup -1}. Based on these findings, the EtOAc extract was fractionated by silica gel column chromatography into nine fractions. The hexane and CHCl{sub 3} fractions showed varied levels of antifungal activity against all test yeasts. Further column chromatography separation of the hexane fraction afforded the pure ...
On February 9, 1995 ComEd experienced a pipe type cable failure on 138kV line 13717. Line 1737 is a bulk power transmission cable circuit connecting The Fisk and Crawford generating stations located within city limits. The line is approximately 4.5 miles long and was originally installed in 1975. This line is forced cooled, has 2,500 KCMIL copper conductors with 505 mils of paper insulation in an 8 inch pritec coated steel pipe. The splices are constructed with Voltalit castings. The failure occurred approximately 3,500 feet from Crawford Station. It was easy to locate the failure since the cable joint casing was breached resulting in the loss of approximately 2,600--2,700 gallons of dielectric fluid. Upon field examination B Phase was determined to have failed. The failure occurred 12 inches inside the casing in an area where it was impossible to install a long connector or add an additional short length of cable to create a piece out. The cause of the failure is ...
The main LHC superconducting magnets (dipoles and quadrupoles) use Rutherford type cables, stabilized electrically and thermally with copper profiles. The portions of cables are connected to each other by a soft soldering technique (Sn96Ag4) with an overlapping length corresponding to one pitch of the superconducting strands. The splice constitutes a "composite" structure with the interchanging layers of Sn96Ag4 and NbTi superconductor, located inside a Cu cage. In order to ensure a high level of reliability (failure probability not exceeding 10-8) for some 10000 connections in the LHC, a non-destructive technique to check the quantity of solder in the joint is foreseen. The technique is based on a gamma ray source (241Am) and the detection is position-sensitive in the transmission mode. Scintillating detectors of gamma rays are used and their accumulated length corresponds to the length of the radioactive source (120 mm). The method can be used in-situ, the ...
In 1976, the US Department of Energy and New York State - ERDA granted a contract for the development of a +-600 kV dc underground transmission cable system looking to inevitable future requirements in the US for economic, high-capacity, long-distance underground transmission linking remote generating stations to metropolitan load centers. This project was comprehensive and dealt with three separate system components, i.e., cable, splice, and terminals. In each instance, for each component, development required an intensive R and D effort, focused on the following categories: insulating materials, model testing, design of full-scale prototype, manufacturer of prototype, and laboratory development testing. Insulating papers and oils were selected, and model studies performed, for both self-contained type and pipe type oil-filled cables. However, only the pipe cable design was finally designated for full-size cable manufacture and EHV laboratory testing. Each of the ...
To understand the molecular mechanisms of how 5^oC-incubation activates mRNA expression of Hsp70a and Samui genes in Bombyx mori diapause eggs, we first searched the 5'-upstream regions of the Hsp70a and Samui genes for heat shock elements (HSEs) and found two regions [Hsp70aHSE-1 (-95 to -58) and -2 (-145 to -121), and SamuiHSE-1 (-84 to -55) and -2 (-304 to -290)] corresponding to HSEs (repeats of nGAAn and/or nTTCn). We cloned four cDNAs encoding heat shock factor (HSF)-a2 (627 amino acids), -b (685 aa), -c (682 aa) and -d (705 aa), which were produced by alternative splicing. When we exposed diapause eggs to 5^oC beginning at 2 day post-oviposition to break diapause, HSFd mRNA only increased after chilling for 6-8 days, a pattern very similar to those of Hsp70a and Samui mRNAs. To exam...
A multi-faceted research program has been performed to investigate in detail several aspects of free and forced convective cooling of underground electric cable systems. There were two main areas of investigation. The first one, reported in Volume 1, dealt with the fluid dynamic and thermal aspects of various components of the cable system. In particular, friction factors for laminar flow in the cable pipes with various configurations were determined using a finite element technique; the temperature distributions and heat transfer in splices were examined using a combined analytical numerical technique; the pressure drop and heat transfer characteristics of cable pipes in the transitional and turbulent flow regime were determined experimentally in a model study; and full-scale model experimental work was carried out to determine the fluid dynamic and thermal characteristics of entrance and exit chambers for the cooling oil. The second major area of activity, ...
A multi-faceted research program has been performed to investigate in detail several aspects of free and forced convective cooling of underground electric cable systems. There were two main areas of investigation. The first one reported in this volume dealt with the fluid dynamic and thermal aspects of various components of the cable system. In particular, friction factors for laminar flow in the cable pipes with various configurations were determined using a finite element technique; the temperature distributions and heat transfer in splices were examined using a combined analytical numerical technique; the pressure drop and heat transfer characteristics of cable pipes in the transitional and turbulent flow regime were determined experimentally in a model study; and full-scale model experimental work was carried out to determine the fluid dynamic and thermal characteristics of entrance and exit chambers for the cooling oil. The second major area of activity, ...
Drums is an acronym for Dynamic Rating and Underground Monitoring System, with specific application to high-pressure pipe-type cable systems which are the predominant means of underground electric power transmission in the United States. The primary objective of this EPRI-sponsored feasibility study was to establish the technical feasibility of seven DRUMS functions and two novel DRUMS communication schemes. The seven DRUMS functions which monitor the system's vital and measurable parameters in real time and perform system diagnostics in the event of component deterioration, malfunction or failure are: Real Time Current Monitoring and Rating; Leak Detection and Location; Fault Location; Pothead Monitoring; Oil Monitoring; Pipe Protection; and Splice Monitoring. The two DRUMS communication schemes are internal to the pipe cable system. Mechanical Communication will use pressure pulses to transmit data along the system, while the Electrical Communication ...
The Compton backscatter technique has been applied to lap-joint in aircraft structure in order to determine mass loss due to exfoliative corrosion of the aluminum alloy sheet skin. The mass loss of each layer has been estimated from Compton backscatter A-scan including the aluminum sheet, the corrosion layer, and the sealant. A Compton backscattering imaging system has been also developed to obtain a cross-sectional profile of corroded lap-splices of aging aircraft using a specially designed slit-type camera. The camera is to focus on a small scattering volume inside the material from which the backscattered photons are collected by a collimated scintillator detector for interpretation of material characteristics. The cross section of the layered structure is scanned by moving the scattering volume through the thickness direction of the specimen. The theoretical model of the Compton scattering based on Boltzmann transport theory is presented for quantitative ...
...The+Wiley+Encyclopedia+of+Packaging+Technology%2C+3rd+Edition FO21+Food+Packaging Wiley::The Wiley Encyclopedia of Packaging Technology, 3rd Edition WILEY ...US | HELP Home / Chemistry / Food Science & Technology / Food Processing, Production & Manufacture / Food Packaging / The Wiley Encyclopedia of Packaging Technology, 3rd Edition ...Manufacture Sensory Science Food Biotechnology Food Chemistry Food Engineering Related Titles Food Packaging Brewing Yeast and Fermentation by Chris Boulton, David Quain Food ...Editor) Journal of Food Process Engineering Journal of Food Processing and Preservation Packaging Research in Food Product Design and Development by Howard R. ...
Wound dressings impregnated with silver have a role to play in aiding to reduce both the dressing and wound microbial bioburden. It is therefore imperative that antimicrobial wound dressings have efficacy on a broad range of clinical significant microorganisms. Accordingly, this study aimed to determine the antimicrobial efficacy of a silver alginate dressing against 115 wound isolates that had been isolated routinely from patients at West Virginia University Hospital. Standardised corrected zones of inhibition (CZOIs) were performed on all clinical isolates. It was found that the silver alginate dressing was able to inhibit the growth of all microorganisms tested. In particular, the silver alginate dressing inhibited the growth of Candida albicans and yeasts with CZOI of 3-115 mm. All met...
DFNA5 was first identified as a gene causing autosomal dominant hearing loss (HL). Different mutations have been found, all exerting a highly specific gain-of-function effect, in which skipping of exon 8 causes the HL. Later reports revealed the involvement of the gene in different types of cancer. Epigenetic silencing of DFNA5 in a large percentage of gastric, colorectal and breast tumors and p53-dependent transcriptional activity have been reported, concluding that DFNA5 acts as a tumor suppressor gene in different frequent types of cancer. Despite these data, the molecular function of DFNA5 has not been investigated properly. Previous transfection studies with mutant DFNA5 in yeast and in mammalian cells showed a toxic effect of the mutant protein, which was not seen after transfection ...
Mono- and disubstituted novel derivatives of the heptaene nystatin analog 28,29-didehydronystatin A1 (S44HP, 1) were obtained by chemical modification of the exocyclic C-16 carboxyl and/or an amino group of mycosamine moiety. The strategy of preparation of mono- and double-modified polyene macrolides was based on the use of intermediate hydrophobic N-Fmoc (9-fluorenylmethoxycarbonyl) derivatives that facilitated the procedures of isolation and purification of new compounds. The antifungal activity of the new derivatives was first tested in vitro against yeasts and filamentous fungi, allowing the selection of the most active compounds that were subsequently tested for acute toxicity in mice. 2-(N,N-dimethylamino)ethylamide of 1 (2) and 2-(N,N-dimethylamino)ethylamide of N-fructopyranosyl-28...
Abstract Microbial cells are routinely dried and ground before they are used in metal biosorption studies. In this work, a metal biosorbent was prepared by drying biomass of the yeast Rhodotorula glutinis in an oven at 70C for 24-h followed by grinding. Two forms of the prepared biosorbent particles, washed and unwashed, were examined for their ability to remove lead from solution. It was found that the unwashed biosorbent exhibited higher lead uptake than the washed biosorbent. Analysis of the supernatant of washed cells incubated in water and that of unwashed cells incubated in lead solution revealed the presence of protein, carbohydrates, organic acids and inorganic phosphate. Overall, the washed and unwashed cells leached, respectively, 14.5 and 13.4% of their initial dry weight (100-m...
Background: The environment preferred by Acanthamoeba trophozoites and the mechanism by which the amebae enters the cornea are not yet fully understood. A better understanding of the pathogenesis of this disease may help with prevention and treatment. Purpose: To define the preferred environments for Acanthamoeba survival and proliferation in vitro by examining the effect of tonicity, nutrient concentration, and free chlorine content on Acanthamoeba. Materials and methods: Human corneal isolates of Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites were cultured at 22^oC (room temperature) in PYG (peptone-yeast extract-glucose) medium. The effect of tonicity on amebae was determined by incubating trophozoites in sodium chloride solutions in concentrations ranging from 0% to 1...
The gene encoding the human type I pituitary adenylate cyclase activating polypeptide receptor (ADCYAP1R1) was mapped to chromosome 7 by PCR analysis of genomic DNA from a human/rodent somatic cell hybrid mapping panel. This assignment was confirmed and the gene localized to chromosome band 7p14 by fluorescence in situ hybridization. A yeast artificial chromosome containing ADCYAP1R1 was identified in the CEPH {open_quotes}B{close_quotes} Mega-YAC library. This YAC includes two highly polymorphic dinucleotide repeat sequences that will facilitate genetic studies of the contribution of ADCYAP1R1 in disease states of the central nervous and neuroendocrine systems. 13 refs., 1 fig.
Statistically based experimental designs were applied to screen and optimize the bioleaching of spent hydrocracking catalyst by Penicillium simplicissimum. Eleven factors were examined for their significance on bioleaching using a Plackett-Burman factorial design. Four significant variables (pulp density, sucrose, NaNO"3, and yeast extract concentrations) were selected for the optimization studies. The combined effect of these variables on metal bioleaching was studied using a central composite design (CCD). Second-order polynomials were established to identify the relationship between the recovery percent of the metals and the four significant variables. The optimal values of the variables for maximum metals bioleaching were as follows: pulp density (4.0%, w/v), sucrose (90g/L), NaNO"3 (2...
Curcumin, the yellow pigment from the rhizoma of Curcuma longa, is a widely studied phytochemical with a variety of biological activities. The ongoing research and clinical trials have proved that this natural phenolic compound has great and diverse pharmacological potencies. Beside its effective antioxidant, antiinflammatory, and antimicrobial/antiviral properties, curcumin is also considered as a cancer chemopreventive agent. While the antioxidant activity of curcumin is well documented, its interaction with DNA and RNA is not fully investigated. This study was designed to examine the interactions of curcumin with calf thymus DNA and yeast RNA in aqueous solution at physiological conditions, using constant DNA and RNA concentration (6.25?mM) and various curcumin/polynucleotide (phosphate...
Direct plating, selective enrichment, and cold enrichment followed by secondary selective enrichment procedures were compared for detecting and enumerating Listeria monocytogenes in chopped cabbage stored at 5 degrees C for up to 64 days. Addition of Fe3+ to solid media enhanced detection of the organism. Cold enrichment (5 degrees C) in nutrient broth and brain heart infusion broth followed by secondary enrichment (48 h, 30 degrees C) in Trypticase soy-yeast extract-antibiotic broth and thiocyanate-nalidixic acid broth and plating on selective agar media (Doyle and Schoeni selective enrichment agar [minus acriflavin hydrochloride, supplemented with 5 micrograms of Fe3+/ml] and McBride Listeria agar) resulted in the detection of highest populations. PMID:3111369
We determined the chromosomal localization and structure of the gene encoding human type II inosine 5{prime}-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205), an enzyme associated with cellular proliferation, malignant transformation, and differentiation. Using polymerase chain reaction (PCR) primers specific for type II IMPDH, we screened a panel of human-Chinese hamster cell somatic hybrids and a separate deletion panel of chromosome 3 hybrids and localized the gene to 3p21.1{yields}p24.2. Two overlapping yeast artificial chromosome clones containing the full gene for type II IMPDH were isolated and a physical map of 117 kb of human genomic DNA in this region of chromosome 3 was constructed. The gene for type II IMPDH was localized and oriented on this map and found to span no more than 12.5 kb.
The potential of the yeast Candida tropicalis and Candida guillermondii was evaluated and an isolated partnership of microorganisms of waters of the Medellin River, conformed by two bacteria and one leavening, to degrade the content of organic matter present in wine produced by the factory of Licores and Alcoholes de Antioquia (FLA) in aerobic process with biomass production. For each one of the microorganisms in study this capacity of removal in units of chemical demand of oxygen was quantified (CDO); in addition, parameters were analyzed such as yield of the biomass in relation to the removed CDO and to total reducing sugars (TRS) consumed, time of fermentation and speed of growth different dilutions from wine. Also the possible inhibition was analyzed that the present phenolic compounds in this wine can cause in the biological process of degradation.
Cellulose sausage cellulose casings are used extensively in the manufacture of sausages in meat packaging. After stripping the meat, spent casings mainly contain cellulose and residual meat juice with salt, nitrate and nitrite. Disposal of spent sausage casings has serious economic and environmental concerns for the sausage industry. This work describes bioconversion of spent cellulose casings (SCC) into enzymes, lactic acid and ethanol by using cellulolytic fungi, lactobacillus and yeasts. The solid substrate cultivation (SSC) of Trichoderma reesei RUT C-30 on SCC and blends gave a maximum of 152 filter paper cellulase (FPase) activity and about 100 carboxymethylcellulase activity (CMCase)/g dry weight substrate. The SSC produced enzyme-rich casing with 50 FPase when directly mixed as suc...
In this work, silver-montmorillonite (Ag-MMT) antimicrobial nanoparticles have been obtained by allowing silver ions from nitrate solutions to replace the Na^+ of natural montmorillonite and then to be reduced by a thermal treatment. Ag-MMT were used as active antimicrobial compounds to improve the shelf life of fresh fruit salad. In order to assess their influence on product shelf life, sensorial and microbiological quality has been monitored during the storage. The microbiological quality was determined by monitoring the principal spoilage microorganisms (mesophilic and psychrotrophic bacteria, coliforms, lactic acid bacteria, yeasts and molds). Additionally, the evolution of sensorial quality was assessed by monitoring color, odor, firmness and product overall quality. The Ag-MMT nanopa...
Amphiphysin is a protein concentrated in neuronal synapses and peripherally associated with neurotransmitter vesicles. It is expressed in many neurons of the central and peripheral nervous systems, in the adrenal medulla, in the anterior and posterior pituitary, in cell lines of the endocrine pancreas, and in spermatocytes. Its subcellular localization and tissue distribution indicate a potential involvement in mechanisms of regulated exocytosis. A role in the dynamic organization of the membrane-associated cytoskeleton is suggested by structural homology to the products of two yeast genes, RVS161 and RVS167, whose mutation results in an abnormal actin distribution, disturbs budding morphology, and impairs cell entry into stationary phase. Limited stretches of sequence similarity, including an SH3 domain, are also shared with other actin-binding proteins. Amphiphysin is the dominant autoantigen in paraneoplastic Stiff-Man syndrome, a neurological autoimmune ...
A number of aerobic species capable of decolorizing some of the dyes in a textile mill effluent were isolated. One of the isolates was able to decolorize Terasil black dye under aerobic conditions in the presence of an exogenous carbon source after 5 days. Glucose or starch (%1 ea) are essential for decolorization but the process proceeds faster in the presence of 0.5% yeast extract. Results of the BOD5 show that the untreated effluent samples have a low BOD value, whereas treated samples show an initial increase in BOD up to 15 days followed by a decrease after 20 days. FT-IR and GC-MS data also reveal that the initial components in the untreated effluent disappear after 20 days of treatment, confirming biodegradation of the dye. Phytotoxicity tests on the untreated effluent samples using...
Beside yeasts, lactic acid bacteria (LAB) are the most abundant microbes in must during vinification. Whereas Oenococcos oeni is commercially used as a starter culture for the biological acid reduction in wines, other species are responsible for different types of wine spoilage. Members of the genera Pediococcus, Weissella, Leuconostoc, and Lactobacillus are producers of exopolysaccharide slimes, biogenic amines, acetic acid, and other off-flavors. In order to control microbial growth, different procedures such as heating of must and addition of sulfite or lysozyme from egg white are generally applied. Yet, because of health risks, the application of sulfite should be reduced and lysozyme is not effective against all LAB. In this study, we describe exoenzymes from a Streptomyces sp. strain...
We report an analysis of four strains of baker's yeast (Saccharomyces cerevisiae) using biocavity laser spectroscopy. The four strains are grouped in two pairs (wild type and altered), in which one strain differs genetically at a single locus, affecting mitochondrial function. In one pair, the wild-type rho+ and a rho0 strain differ by complete removal of mitochondrial DNA (mtDNA). In the second pair, the wild-type rho+ and a rho- strain differ by knock-out of the nuclear gene encoding Cox4, an essential subunit of cytochrome c oxidase. The biocavity laser is used to measure the biophysical optic parameter Deltalambda, a laser wavelength shift relating to the optical density of cell or mitochondria that uniquely reflects its size and biomolecular composition. As such, Deltalambda is a powerful parameter that rapidly interrogates the biomolecular state of single cells and mitochondria. Wild-type cells and mitochondria produce Gaussian-like distributions ...
Ethanol has excellent fuel properties, such as high octane, high heat of vaporization and low photochemical reactivity in the atmosphere. It is less volatile than gasoline and there is lower smog formation from evaporative emissions of pure ethanol compared to gasoline. As such, ethanol has emerged as an important alternative energy source that is sustainable, efficient, cost effective, convenient and safe. In 2006, global production of ethanol reached 13.5 billion gallons, up from 12.1 billion gallons in 2005. However, in light of the current debate of food versus fuel, the industry must shift to non-food feedstocks. This paper described an emerging technology to cost-effectively produce ethanol from sweet sorghum stalks, the most promising alternative feedstock to corn, via solid state fermentation (SSF). Experiments of advanced solid state fermentation (ASSF) for ethanol production from sweet sorghum by Saccharomyces cerevisiae were conducted in laboratory and pilot scales studies. ...
The goal of the present work was to determine the impact of N3-methyladenine (3-mA), an important lesion generated by many environmental agents and anticancer drugs, on in vivo DNA replication and in vitro RNA transcription. Due to 3-mA chemical instability, the stable isostere 3-methyl-3-deazaadenine (3-m-c(3)A) was site specifically positioned into an oligodeoxynucleotide. The oligomer was, then incorporated into a vector system that is rapidly converted to ssDNA inside yeast cells and requires DNA replication opposite the lesion for plasmid clonal selection. For control purposes, an adenine or a stable apurinic/apyrimidinic (AP)-lesion was placed at the same site. The presence of each lesion in the oligonucleotide was confirmed by MALDI-TOF analysis. Plasmids were then transfected into yeast cells. While the AP-site dramatically reduced plasmid replication in all strains, the 3-m-c(3)A had a slight effect in the rad30 background which ...
Although some polymer conductors of electricity (ex. Polyanilines) are materials known for more than 100 years, only recently have the interesting chemical, electrical and optic properties of their insulating and conducting forms been recognized. Advances made in the chemistry of polymer conductors have also led to improvements in processing them. This work studies a practical application of these materials: the use of polymer conductors for the remote welding of insulating thermoplastic polymers, using energy from microwaves for the local heating of the union. Many thermoplastics (for ex. Polyethylene) do not absorb, or absorb very little, energy from microwaves. Different conductor materials (conductor polymers, carbon nanotubes), however, heavily absorb energy from microwaves with the resulting heating. In this way the welding zone can be heated without affecting the rest of the piece. Conductor polymers (polyanilines) were synthesized chemically and they were characterized by ...
Hepatic injury and regeneration of the liver are associated with activation of hepatic stellate cells (HSC). Fibroblast growth factors (FGFs) and their receptors are important regulators of repair in various tissues. HSC express FGFR3IIIc as well as FGFGR4 and different spliced FGFR1IIIc and FGFR2IIIc isoforms which differ in the presence or absence of the acid box and of the first Ig-like domain. Expression of FGF9, known to be capable to activate the HSC FGFR2/3-isoforms, was increased in HSC in liver slice cultures after exposition to carbon tetrachloride, as an acute liver injury model. FGF9 significantly stimulated 3-H thymidine incorporation of hepatocytes, but failed to induce DNA synthesis in HSC despite the fact that FGF9 induced a sustained activation of extracellular signal-related kinases (ERK) 1/2. FGF9 induced an increased phosphorylation of Tyr436 of the fibroblast growth factor receptor substrate (FRS) 2, while phosphorylation of Tyr196 which is ...
When a shortened enzymatic version of the Tetrahymena self-splicing intervening sequence (IVS) RNA is placed under catalytic conditions and irradiated at 254 nm, a covalent cross-link forms with high efficiency. The position of the cross-link was mapped by using three independent methods: RNase H digestion, primer extension with reverse transcriptase, and partial hydrolysis of end-labeled RNA. The cross-link is chemically unusual in that it joins two adenosines, A57 and A95. Formation of this cross-link depends upon the identity and concentration of divalent cations present and upon heat-cool renaturation of the IVS in a manner that parallels conditions required for optimal catalytic activity. Furthermore, cross-linking requires the presence of sequences within the core structure, which is conserved among group I intervening sequences and necessary for catalytic activity. Together these correlations suggest that a common folded structure permits cross-linking and ...
Mutations in the FGD1 gene have been shown to cause Aarskog-Scott syndrome (AAS), or facio-digito-genital dysplasia (OMIM#305400), an X-linked disorder characterized by distinctive genital and skeletal developmental abnormalities with a broad spectrum of clinical phenotypes. To date, 20 distinct mutations have been reported, but little phenotypic data are available on patients with molecularly confirmed AAS. In the present study, we report on our experience of screening for mutations in the FGD1 gene in a cohort of 60 European patients with a clinically suspected diagnosis of AAS. We identified nine novel mutations in 11 patients (detection rate of 18.33%), including three missense mutations (p.R402Q; p.S558W; p.K748E), four truncating mutations (p.Y530X; p.R656X; c.806delC; c.1620delC), one in-frame deletion (c.2020_2022delGAG) and the first reported splice site mutation (c.1935+3A>C). A recurrent mutation (p.R656X) was detected in three independent families. ...
The ability of residual biomass from the thermotolerant ethanol-producing yeast strain Kluyveromyces marxianus IMB3 to function as a biosorbent for uranium has been examined. It was found that the biomass had an observed maximum biosorption capacity of 120 mg U/g dry weight of biomass. The calculated value for the biosorption maximum, obtained by fitting the data to the Langmuir model was found to be 130 mg U/g dry weight biomass. Maximum biosorption capacities were examined at a number of temperatures and both the observed and calculated values obtained for those capacities increased with increasing temperature. Decreasing the pH of the biosorbate solution resulted in a decrease in uptake capacity. When biosorption reactions were carried out using sea-water as the diluent it was found that the maximum biosorption capacity of the biomass increased significantly. Using transmission electron microscopy, uranium crystals were shown to be concentrated on the outer ...
A series of 2-alkylthiopyrine-4-carbothioamides were synthesized, and their anti-fungal potency was tested. The chemical structures were proved by infrared spectroscopy (IR) and {sup 1}H nuclear magnetic resonance ({sup 1}H-NMR) data and by elemental analysis. The minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) assessment were used for the estimation of potential activity in vitro. The study comprising 21 clinical isolates of fungi showed that two compounds exhibited fair inhibitory activity against some yeasts and dermatophytes. Selective fungistatic activity against non-dermatophytes (MIC = 3.12-25.0 {mu}g/mL) was found also in another compound. None of the above compounds showed inhibitory activity against non-dermatophyte filamentous fungi. Microbiological activity of 2-alkylthiopyridine-4-carbothioamides appears to be mainly related to hydrophobicity of alkyl in position 2. (authors). 10 refs., 8 tabs.
Transcriptional regulation of the galactose-metabolizing genes in Saccharomyces cerevisiae depends on three core proteins: Gal4p, the transcriptional activator that binds to upstream activating DNA sequences (UASGAL); Gal80p, a repressor that binds to the carboxyl terminus of Gal4p and inhibits transcription; and Gal3p, a cytoplasmic transducer that, upon binding galactose and adenosine 5'-triphosphate, relieves Gal80p repression. The current model of induction relies on Gal3p sequestering Gal80p in the cytoplasm. However, the rapid induction of this system implies that there is a missing factor. Our structure of Gal80p in complex with a peptide from the carboxyl-terminal activation domain of Gal4p reveals the existence of a dinucleotide that mediates the interaction between the two. Biochemical and in vivo experiments suggests that nicotinamide adenine dinucleotide phosphate (NADP) plays a key role in the initial induction event.
The uncoupling protein (UCP) is a proton/anion transporter found in the inner mitochondrial membrane of brown adipocyte. Although UCP has nor been detected in mitochondria from any other tissue, it shares structural and catalytic properties with several other mitochondrial carrier proteins. Although UCP was discovered only recently it is one of the most extensively studied mitochondrial carrier proteins.More recently, the mouse, rat, and human genes encoding for UCP have been isolated and sequenced. The availability of these various tools has led to several significant observations. UCP gene expression is strongly controlled at the level of transcription by signals that are activated after the stimulation of brown adipocytes by norepinephrine. The comparison of UCP gene with the genes encoding the adenine nucleotide translocator revealed the existence of structural and evolutionary homologies. Moreover, in humans the UCP gene and one form of adenine nucleotide translocator gene are ...
All organisms, from bacteria and yeast to humans, respond to physical and chemical stressors by increasing the synthesis of a small group of cellular stress proteins.'' The authors have developed a simple in vitro system for quickly screening environmentally relevant stressors to detect stress-induced proteins that are good candidates for biomarkers. Polyacrylamide gel electrophoresis was used to detect stressor-induced, concentration-dependent changes in cellular stress protein levels in two fish cell culture systems, whereas simultaneous in vitro neutral red uptake cytotoxicity assays measured the stressors effect on cellular physiology. There was a direct concentration-dependent relationship between sublethal cytotoxic effects and the increases in stress protein levels. Increases of 50 to 200% were detected in stress proteins from desert topminnow, Poeciliopsis lucida, hepatoma-derived cell cultures exposed to cadmium or copper. Three proteins ...
Escherichia coli B and K-12 are equally susceptible to the bacteriostatic effects of aerobic paraquat, but they differed strikingly when the lethality of paraquat was evaluated. E. coli B suffered an apparent loss of viability when briefly exposed to paraquat, whereas E. coli K-12 did not. This difference depended on the ability of the B-strain, but not the K-12 strain, to retain internalized paraquat; the B strain was killed on aerobic tryptic soy-yeast extract plates during the incubation which preceded the counting of colonies. This difference in retention of paraquat between strains was demonstrated by delayed loss of viability, by growth inhibition, and by cyanide-resistant respiration after brief exposure to paraquat, washing, and testing in fresh medium. This difference was also shown by using ({sup 14}C)paraquat. This previously unrecognized difference between E. coli B and K-12 has been the cause of apparently contradictory reports and should lead to some ...
The authors describe a cloning strategy for the construction of a human genomic library in yeast artificial chromosomes (YACs) based on complete digestion of high-molecular-weight DNA with the infrequently cutting restriction enzyme MluI. Cloning of MluI fragments in the vector pYAC-RC and one subsequent size fractionation by preparative pulsed-field gel electrophoresis yielded a library with average insert sizes of 600 kb. Ninety-seven percent of the colonies were recombinant. An additional size fractionation of MluI fragments prior to ligation had no significant influence on the size of the YACs. The library currently consists of 5000 clones, which is the equivalent of one human genome. Nineteen percent of the YACs were larger than 1.2 Mb. Since smaller MluI fragments are lost during sizing, they also performed cloning without size fractionation. Only 20% of the colonies were recombinant, probably due to unligated vector fragments that were present during the ...
Two overlapping cDNA clones encoding human DNA topoisomerase II were identified by two independent methods. In one, a human cDNA library in phage {lambda} was screened by hybridization with a mixed oligonucleotide probe encoding a stretch of seven amino acids found in yeast and Drosophila DNA topoisomerase II; in the other, a different human cDNA library in a {lambda}gt11 expression vector was screened for the expression of antigenic determinants that are recognized by rabbit antibodies specific to human DNA topoisomerase II. The entire coding sequences of the human DNA topoisomerase II gene were determined from these and several additional clones, identified through the use of the cloned human TOP2 gene sequences as probes. Hybridization between the cloned sequences and mRNA and genomic DNA indicates that the human enzyme is encoded by a single-copy gene. The location of the gene was mapped to chromosome 17q21-22 by in situ hybridization of a cloned fragment to ...
The potential of the dried yeast, wild-type Schizosaccharomyces pombe, to remove Ni(II) ion was investigated in batch mode under varying experimental conditions including pH, temperature, initial metal ion concentration and biosorbent dose. Optimum pH for biosorption was determined as 5.0. The highest equilibrium uptake of Ni(II) on S. pombe, q e, was obtained at 25??C as 33.8?mg?g?1. It decreased with increasing temperature within a range of 25?50??C denoting an exothermic behaviour. Increasing initial Ni(II) concentration up to 400?mg?L?1 also elevated equilibrium uptake. No more adsorption took place beyond 400?mg?L?1. Equilibrium data fitted better to Langmuir model rather than Freundlich model. Sips, Redlich?Peterson, and Kahn isotherm equations modelled the investigated system with a...
This presentation describes a method for separating {sup 14}C-hexose from {sup 14}C-sucrose in extracts of plant tissue. Portions of ethanol extracts are treated with activated charcoal in microcentrifuge tubes. Aliquots are removed, ethanol evaporated and replaced with reaction mixture that phosphorylates hexose (HEPPS, K{sub 2}HPO{sub 4}, Mg(C{sub 2}H{sub 3}O{sub 2}){sub 2}, ovalbumen, Na{sub 2}ATP, yeast hexokinase). After a time course, the hexokinase reaction is stopped (slowed considerably) to minimize effects of contamination enzyme activities. The stopping agent used is lyxose, a nonphosphorylable analogue of glucose. The strong anionic charge of phosphate introduced through the hexokinase action results in binding (> 95%) of hexose-phosphate to anion-exchange resin. Sucrose remains unbound (> 95%) in solution. This batch ion-exchange is performed in microcentrifuge tubes to allow many samples to be processed simultaneously. Recovery of radiolabel in ...
Chorismate mutase, a branch-point enzyme in the aromatic amino acid pathway of Saccharomyces cerevisiae, and also a mutant chorismate mutase with a single amino acid substitution in the C-terminal part of the protein have been purified approximately 20-fold and 64-fold from overproducing strains, respectively. The wild-type enzyme is activated by tryptophan and subject to feedback inhibition by tyrosine, whereas the mutant enzyme does not respond to activation by tryptophan nor inhibition by tyrosine. Both enzymes are dimers consisting of two identical subunits of M_r 30,000, each one capable of binding one substrate and one activator molecule. Each subunit of the wild-type enzyme also binds one inhibitor molecule, whereas the mutant enzyme lost this ability. The enzyme reaction was observed by "1H NMR and shows a direct and irreversible conversion of chorismate to prephenate without the accumulation of any enzyme-free intermediates. The kinetic data of the wild-type chorismate mutase ...
Biosorption of uranium by residual biomass from The Old Bushmill`s Distillery Co. Ltd., Bushmills, Co. Antrim, Northern Ireland, following exposure to short and intense electric pulses has been examined. The biomass was prepared from the distillery spent wash and consisted of non-viable yeast and bacterial cells. As shown previously, untreated biomass had a maximum biosorption capacity of 170 mg uranium/g dry weight biomass. When biosorption reactions were placed between two electrodes and exposed to electric pulses with field strengths ranging from 1.25-3.25 kV/cm at a capacitance of 25 {mu}F, biosorption increased from 170 mg of uranium to 275 mg uranium/g dry weight biomass. The data were obtained from biosorption isotherm analyses and taken as the degree of biosorption at residual uranium concentrations of 3 mM. In addition, when the capacitance of the electric pulses increased from 0.25 {mu}F to 25 {mu}F at a fixed pulse field strength the degree of ...
The changes in quality of irradiated spices, i.e., nutmeg (Myristica fragrans), black pepper and white pepper (Piper nigrum) stored in different indigenous packaging materials were evaluated. Packaging materials used were tin cans; tin can lined with polypropylene film, tin can lined with wrapping paper, woven polypropylene bag and woven polypropylene bag lined with polypropylene film. Packaging in woven polypropylene bag could cause significant changes in a_w-values and moisture contents of the spices. In the tin can, no significant change was found during storage. By applying a polypropylene film liner inside the plastic bag, the changes could be retarded. The other parameters observed, i.e. total plate count, total mould and yeast count and organoleptic scores of the samples were not significantly affected by the packaging method. A dose of 5 kGy could reduce the microbial load of the spices by about 2-3 log cycles. A significant decrease in a_w-value and ...
A gene designated BRCA1, implicated in the susceptibility to early-onset familial breast cancer, has recently been localized to chromosome 17q12-q21. To date, the order of DNA markers mapped within this region has been based on genetic linkage analysis. The authors report the use of multicolor fluorescence in situ hybridization to establish a physically based map of five polymorphic DNA markers and 10 cloned genes spanning this region. Three cosmid clones and Alu-PCR-Generated products derived from 12 yeast artificial chromosome clones representing each of these markers were used in two-color mapping experiments to determine an initial proximity of markers relative to each other on metaphase chromosomes. Interphase mapping was then employed to determine the order and orientation of closely spaced loci by direct visualization of fluorescent signals following hybridization of three probes, each detected in a different color. Statistical analysis of the combined data ...
Cdc7 kinase plays an essential role in firing of replication origins by phosphorylating components of the replication complexes. Cdc7 kinase has also been implicated in S phase checkpoint signaling downstream of the ATR and Chk1 kinases. Inactivation of Cdc7 in yeast results in arrest of cell growth with 1C DNA content after completion of the ongoing DNA replication. In contrast, conditional inactivation of Cdc7 in undifferentiated mouse embryonic stem (ES) cells leads to growth arrest with rapid cessation of DNA synthesis, suggesting requirement of Cdc7 functions for continuation of ongoing DNA synthesis. Furthermore, loss of Cdc7 function induces recombinational repair (nuclear Rad51 foci) and G2/M checkpoint responses (inhibition of Cdc2 kinase). Eventually, p53 becomes highly activated and the cells undergo massive p53-dependent apoptosis. Thus, defective origin activation in mammalian cells can generate DNA replication checkpoint signals. Efficient removal of ...
A novel, obligately anaerobic, extremely thermophilic, cellulolytic bacterium, designated OB47T, was isolated from Obsidian Pool, Yellowstone National Park, WY, USA. The isolate was a non-motile, non-spore forming, Gram-positive rod approximately 2 m long by 0.2 m wide and grew at temperatures between 55-85oC with the optimum at 78oC. The pH range for growth was 6.0-8.0 with values of near 7.0 being optimal. Growth on cellobiose produced the fastest specific growth rates at 0.75 hr-1. The organism also displayed fermentative growth on glucose, maltose, arabinose, fructose, starch, lactose, mannose, sucrose, galactose, xylose, arabinogalactan, Avicel, xylan, filter paper, processed cardboard, pectin, dilute acid-pretreated switchgrass and Populus. OB47T was unable to grow on mannitol, fucose, lignin, Gelrite, acetate, glycerol, ribose, sorbital, carboxymethylcellulose and casein. Yeast extract stimulated growth and thiosulfate, sulfate, nitrate, and sulfur were not ...
Numerous studies have investigated degradation of individual endocrine disrupting compounds (EDCs) in lab or natural waters. However, natural variations in water matrices and mixtures of EDCs in the environment may confound analysis of the treatment efficiency. Because chemical based analytical methods cannot represent the combined or synergistic activities between water quality parameters and/or the EDC mixtures at environmentally relevant concentrations ({mu}g L{sup -1}-ng L{sup -1}), bioanalytical assessments of residual estrogenic activity in treated water were used to evaluate the performance of the UV based advanced oxidation process for estrogenic contaminants in water. Four EDCs including estradiol (E{sub 2}), ethinyl estradiol (EE{sub 2}), bisphenol-A (BPA) and nonylphenol (NP) were spiked individually or as a mixture at {mu}g L{sup -1}-ng L{sup -1} in laboratory or natural river water. The removal rates of estrogenic activity were quantitatively evaluated by in vitro ...