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2.
Arch Pediatr ; 25(2): 95-99, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29395890

ABSTRACT

BACKGROUND: In the context of shorter hospital stays in maternity units, in 2014 the French health authorities issued guidelines for newborn follow-up after discharge from maternity units. A medical visit is recommended between the 6th and 10th day of life, as are home visits from midwives. This study was designed to evaluate compliance with these guidelines. METHODS: The study was observational, prospective, multicenter, and was conducted in March and April 2015 in three maternity units in northern France that participate in the Baby Friendly Hospital Initiative (BFHI). Follow-up practices (medical visit between the 6th and 10th day, home visits from a midwife) and demographic, social, and medical data were recorded during the stay in the maternity unit, and through a phone interview 1 month later, in singleton term-born infants. RESULTS: The study population included 108 mother-infant pairs. The recommended medical visit was effectively performed by a physician between the 6th and 10th day of life for 20 newborns (19%) (95% CI: [11; 26]). During the 1st month, at least one home visit from a midwife was recorded for 96 mother-infant pairs (89%). The only factor positively correlated with a medical visit between the 6th and 10th day was the mother's choice, made early during the hospital stay and independently of the real length of stay, for early discharge from the maternity unit. CONCLUSION: Compliance with national guidelines was poor for the recommended medical visit between the 6th and 10th day of life. Information needs to be improved.


Subject(s)
Aftercare/standards , Guideline Adherence/statistics & numerical data , Patient Discharge , Adult , Female , Follow-Up Studies , France , Hospital Units , Humans , Infant, Newborn , Male , Prospective Studies
3.
Phys Rev Lett ; 118(24): 242502, 2017 Jun 16.
Article in English | MEDLINE | ID: mdl-28665637

ABSTRACT

The level structure of the neutron-rich ^{77}Cu nucleus is investigated through ß-delayed γ-ray spectroscopy at the Radioactive Isotope Beam Factory of the RIKEN Nishina Center. Ions of ^{77}Ni are produced by in-flight fission, separated and identified in the BigRIPS fragment separator, and implanted in the WAS3ABi silicon detector array, surrounded by Ge cluster detectors of the EURICA array. A large number of excited states in ^{77}Cu are identified for the first time by correlating γ rays with the ß decay of ^{77}Ni, and a level scheme is constructed by utilizing their coincidence relationships. The good agreement between large-scale Monte Carlo shell model calculations and experimental results allows for the evaluation of the single-particle structure near ^{78}Ni and suggests a single-particle nature for both the 5/2_{1}^{-} and 3/2_{1}^{-} states in ^{77}Cu, leading to doubly magic ^{78}Ni.

4.
J Biopharm Stat ; 27(6): 1054-1072, 2017.
Article in English | MEDLINE | ID: mdl-28375746

ABSTRACT

For about a decade, early clinical development in oncology is facing new challenges. This is due to two main reasons. The first one is linked to the developed molecular targeted agents (MTA) themselves for which the maximum tolerated dose (MTD) is no longer the only dose of interest. The second reason is related to the fact that costs and attrition rates are huge. When selecting a dose, evidence of early activity signal becomes required for future engagements. This implies the need to handle both toxicity and activity endpoints in the analysis and also in the dose escalation design of early-phase trials. We propose a model-based design taking into account both safety and activity for dose escalation. The proposed model involves a bivariate Gaussian latent variable depending on a monotonic toxicity curve and a quadratic activity curve. This model is fitted under the Bayesian framework that allows the incorporation of prior information. The predictive distributions of dose-response curves are used to lead the dose recommendation. Uncertainty in the dose-response relationship is taken into account to calculate the probability of being an over-toxic or a target dose. The proposed design is compared to two other widely used methods.


Subject(s)
Antineoplastic Agents/therapeutic use , Clinical Trials as Topic/statistics & numerical data , Endpoint Determination/statistics & numerical data , Maximum Tolerated Dose , Neoplasms/drug therapy , Antineoplastic Agents/adverse effects , Clinical Trials as Topic/methods , Endpoint Determination/methods , Humans , Medical Oncology/methods , Medical Oncology/statistics & numerical data , Neoplasms/epidemiology , Risk Factors , Treatment Outcome
5.
Phys Rev Lett ; 116(18): 182501, 2016 May 06.
Article in English | MEDLINE | ID: mdl-27203316

ABSTRACT

The N=48 ^{80}Ge nucleus is studied by means of ß-delayed electron-conversion spectroscopy at ALTO. The radioactive ^{80}Ga beam is produced through the isotope separation on line photofission technique and collected on a movable tape for the measurement of γ and e^{-} emission following ß decay. An electric monopole E0 transition, which points to a 639(1) keV intruder 0_{2}^{+} state, is observed for the first time. This new state is lower than the 2_{1}^{+} level in ^{80}Ge, and provides evidence of shape coexistence close to one of the most neutron-rich doubly magic nuclei discovered so far, ^{78}Ni. This result is compared with theoretical estimates, helping to explain the role of monopole and quadrupole forces in the weakening of the N=50 gap at Z=32. The evolution of intruder 0_{2}^{+} states towards ^{78}Ni is discussed.

6.
Bioinformatics ; 30(17): i386-92, 2014 Sep 01.
Article in English | MEDLINE | ID: mdl-25161224

ABSTRACT

MOTIVATION: The spatial conformation of the chromosome has a deep influence on gene regulation and expression. Hi-C technology allows the evaluation of the spatial proximity between any pair of loci along the genome. It results in a data matrix where blocks corresponding to (self-)interacting regions appear. The delimitation of such blocks is critical to better understand the spatial organization of the chromatin. From a computational point of view, it results in a 2D segmentation problem. RESULTS: We focus on the detection of cis-interacting regions, which appear to be prominent in observed data. We define a block-wise segmentation model for the detection of such regions. We prove that the maximization of the likelihood with respect to the block boundaries can be rephrased in terms of a 1D segmentation problem, for which the standard dynamic programming applies. The performance of the proposed methods is assessed by a simulation study on both synthetic and resampled data. A comparative study on public data shows good concordance with biologically confirmed regions. AVAILABILITY AND IMPLEMENTATION: The HiCseg R package is available from the Comprehensive R Archive Network and from the Web page of the corresponding author.


Subject(s)
Chromosomes, Mammalian/chemistry , Animals , Chromatin/chemistry , Chromosomes, Human/chemistry , High-Throughput Nucleotide Sequencing , Humans , Mice , Models, Statistical , Sequence Analysis, DNA
8.
BJOG ; 115(12): 1538-46, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19035990

ABSTRACT

OBJECTIVES: To describe the management of threatened preterm delivery (TPD) in France 3 years after publication of the French guidelines and to analyse the factors of variation of the practices observed. DESIGN: Population-based study. SETTING: Representative sample of French maternity units. The study included 107 hospitals, accounting for 20% of all French maternity units. POPULATION: Women hospitalised for TPD during May 2005. METHODS: Cross-sectional national practice survey. RESULTS: Of the 734 admissions for TPD, 12.1% involved premature rupture of membranes and 12.9% were in utero transfers. Women admitted for TPD accounted for roughly 6% of all annual deliveries, regardless of the unit's level of care, and 42.4% of these women delivered preterm: none delivered before 32 weeks in level 1 maternity units, 11.6% in level 2 and 88.4% in level 3. Transvaginal cervical ultrasound was performed for 54.5% of the women with intact membranes. Tocolysis was administered in 87.1% of women with intact membranes, with 45.6% of such women receiving this intervention for longer than 48 hours. First-line tocolytics used were calcium channel blockers (53.7%), beta-agonists (34.7%) or atosiban (8.8%), but their distribution differed substantially according to level of care. Maintenance tocolysis was administered to 385 women (59.8%) with intact membranes. Of the women admitted before 34 weeks, 21.1% did not receive corticosteroids. CONCLUSIONS: Practices for the management of TPD vary widely and appear to depend on the level of care. Some practices appear less than optimal, especially those related to duration of tocolysis, maintenance tocolysis, antenatal corticosteroid and use of cervical ultrasound.


Subject(s)
Abortion, Threatened/prevention & control , Obstetric Labor, Premature/prevention & control , Perinatal Care/standards , Professional Practice/standards , Tocolytic Agents/therapeutic use , Abortion, Threatened/diagnosis , Adrenal Cortex Hormones/therapeutic use , Cross-Sectional Studies , Female , France , Hospitalization/statistics & numerical data , Hospitals, Maternity/statistics & numerical data , Humans , Maternal Age , Obstetric Labor, Premature/diagnosis , Parity , Physical Examination , Pregnancy , Pregnancy Trimesters , Random Allocation
9.
Appl Microbiol Biotechnol ; 62(4): 349-55, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12743752

ABSTRACT

A well-known industrial fungus for enzyme production, Aspergillus niger, was selected to produce the feruloyl esterase FAEA by homologous overexpression for pulp bleaching application. The gpd gene promoter was used to drive FAEA expression. Changing the nature and concentration of the carbon source nature (maltose to glucose; from 2.5 to 60 g l(-1)), improved FAEA activity 24.5-fold and a yield of 1 g l(-1) of the corresponding protein in the culture medium was achieved. The secreted FAEA was purified 3.5-fold to homogeneity in a two-step purification procedure with a recovery of 69%. The overproduced protein was characterised and presented properties in good agreement with those of native FAEA. The recombinant FAEA was tested for wheat straw pulp bleaching, with or without a laccase mediator system and xylanase. Best results were obtained using a bi-sequential process with a sequence including xylanase, FAEA and laccase, and yielded very efficient delignification--close to 75%--and a kappa number of 3.9. This is the first report on the potential application of recombinant FAEA in the pulp and paper sector.


Subject(s)
Aspergillus niger/enzymology , Carboxylic Ester Hydrolases , Industry , Paper , Aspergillus niger/genetics , Biotechnology/methods , Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/genetics , Carboxylic Ester Hydrolases/isolation & purification , Carboxylic Ester Hydrolases/metabolism , Endo-1,4-beta Xylanases/metabolism , Genetic Vectors , Laccase/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Transformation, Genetic , Triticum/metabolism
10.
J Appl Microbiol ; 94(4): 618-24, 2003.
Article in English | MEDLINE | ID: mdl-12631197

ABSTRACT

AIMS: Laccase production by the monokaryotic strain Pycnoporus cinnabarinus ss3 was studied using ethanol as inducer in the culture medium. METHODS AND RESULTS: The effect of ethanol was tested at 10, 20, 30, 35 and 45 g l-1 and compared with that of ferulic acid, known until now as the most efficient inducer for laccase expression by P. cinnabarinus ss3. In the presence of 35 g l-1 ethanol, laccase activity (266 600 U l-1) and productivity (19 000 U l-1 day-1) were nine and fivefold higher compared with ferulic acid-induced cultures, and 155- and 65-fold higher compared with non-induced cultures, respectively. In vivo, ethanol added to the culture medium of P. cinnabarinus ss3 favoured a continuous and high expression of laccase gene. Under these conditions, P. cinnabarinus ss3 produced preferentially the isoenzyme LAC I. Ethanol added in vitro to the purified P. cinnabarinus ss3 laccase typically inhibited the enzymatic activity. CONCLUSIONS: In spite of an initial inhibitory effect on mycelial growth, ethanol was shown to be a very strong inducer for laccase expression by P. cinnabarinus ss3 allowing an average yield of 1-1.5 g l-1 laccase. SIGNIFICANCE AND IMPACT OF THE STUDY: This study identified P. cinnabarinus ss3 as an outstanding producer of laccase in the presence of ethanol as inducer. Ethanol is an inexpensive agricultural by-product and the process is simple to scale-up for industrial production.


Subject(s)
Basidiomycota/metabolism , Ethanol/pharmacology , Oxidoreductases/biosynthesis , Basidiomycota/drug effects , Basidiomycota/growth & development , Coumaric Acids/pharmacology , Culture Media , Dose-Response Relationship, Drug , Laccase , Oxidoreductases/isolation & purification
11.
Bioessays ; 23(9): 807-19, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11536293

ABSTRACT

Comparisons between related species often allow the detailed genetic analysis of evolutionary processes. Here we advocate the use of the nematode Caenorhabditis elegans (and several other rhabditid species) as model systems for microevolutionary studies. Compared to Drosophila species, which have been a mainstay of such studies, C. elegans has a self-fertilizing mode of reproduction, a shorter life cycle and a convenient cell-level analysis of phenotypic variation. Data concerning its population genetics and ecology are still scarce, however. We review molecular, behavioral and developmental intraspecific polymorphisms for populations of C. elegans, Oscheius sp. 1 and Pristionchus pacificus. Focusing on vulval development, which has been well characterized in several species, we discuss relationships between patterns of variations: (1) for a given genotype (developmental variants), (2) after mutagenesis (mutability), (3) in different populations of the same species (polymorphisms) and (4) between closely related species. These studies have revealed that evolutionary variations between sister species affect those characters that show phenotypic developmental variants, that are mutable and that are polymorphic within species.


Subject(s)
Biological Evolution , Nematoda/classification , Nematoda/genetics , Polymorphism, Genetic , Animals , Caenorhabditis elegans/genetics , Drosophila/genetics , Genetic Techniques , Genetic Variation , Genotype , Mutagenesis
12.
Dev Biol ; 232(2): 362-71, 2001 Apr 15.
Article in English | MEDLINE | ID: mdl-11401398

ABSTRACT

In Caenorhabditis elegans, two lateral blast cells called P11/12L and P11/12R are symmetric left-right homologs at hatching, migrate subsequently in opposite anteroposterior directions during the first larval stage, and adopt two different fates, thus breaking the symmetry between them. Our results show that, unlike most other cell fate decisions in C. elegans, the orientation of P11/12L/R migration is highly biased, but not fixed. The handedness of their migration is linked to whole body handedness and is randomized in lin-12/Notch mutants and by ablation of the Y cell. Migration handedness is independent of P11 and P12 fate determination, previously shown to require the LIN-44/Wnt and the LIN-3/EGF pathways (L. I. Jiang and P. W. Sternberg, 1998, Development 125, 2337-2347). We further show that several changes in P11/12L/R asymmetry have occurred during nematode evolution: loss of asymmetry or reversals in orientation of migration. Strikingly, for most species studied, handedness of migration is highly biased but not fixed. Thus, whereas the final cell fate pattern of P11/12 is invariant, the developmental route leading to it is subject both to developmental indeterminacy and to evolutionary variations.


Subject(s)
Caenorhabditis elegans/growth & development , Nematoda/growth & development , Animals , Biological Evolution , Body Patterning/genetics , Caenorhabditis elegans/cytology , Caenorhabditis elegans/genetics , Cell Communication/genetics , Cell Movement/genetics , Mutation , Nematoda/cytology , Nematoda/genetics , Species Specificity
13.
Curr Biol ; 11(9): 631-43, 2001 May 01.
Article in English | MEDLINE | ID: mdl-11369226

ABSTRACT

BACKGROUND: The cell lineage of nematodes is mostly invariant for a given species, but varies between species. One can thus wonder how a cell lineage varies during evolution. We have started a microevolutionary approach within two genera by observing lineage variations of vulval precursor cells in different natural nematode populations of the same and closely related species. RESULTS: In Caenorhabditis elegans, the P3.p cell lineage is variable within a genetically homogeneous population and polymorphic between wild strains. Irrespective of its division pattern, P3.p is competent to form vulval tissue in different C. elegans strains, whereas it is not competent in C. briggsae. In Oscheius sp. 1, P4.p and P8.p lineages are strongly polymorphic. Within each genus, these intraspecies polymorphisms in cell lineages are amplified between closely related species. In Oscheius sp. 1, the large polymorphisms in P4.p and P8.p lineages allowed us to undertake a genetic analysis of the variation between two pairs of strains. Multiple loci are involved in cell lineage differences, and variation at one locus appears to have a relatively strong effect. In addition to these large lineage variations in cells that do not normally contribute to the vulva, we find minor variations (errors) in vulval lineages, which represent the precision level of the vulval-patterning process and point to a selection pressure for maintenance of a large vulval equivalence group. CONCLUSIONS: Polymorphisms in vulval cell lineage are found within a given nematode species, and could be instrumental in explaining evolutionary variations between closely related species.


Subject(s)
Biological Evolution , Nematoda/cytology , Nematoda/genetics , Polymorphism, Genetic , Vulva/cytology , Animals , Cell Lineage , Female , Species Specificity
14.
Lett Appl Microbiol ; 32(4): 262-7, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11298938

ABSTRACT

AIMS: The biotransformation of L-phenylalanine into benzaldehyde (bitter almond aroma) was studied in the strain Trametes suaveolens CBS 334.85. METHODS AND RESULTS: Cultures of this fungus were carried out in the absence or in the presence of HP20 resin, a highly selective adsorbent for aromatic compounds. For the identification of the main catabolic pathways of L-phenylalanine, a control medium (without L-phenylalanine) was supplemented with each of the aromatic compounds, previously detected in the culture broth, as precursors. Trametes suaveolens CBS 334.85 was shown to biosynthesize benzyl and p-hydroxybenzyl derivatives, particularly benzaldehyde, and large amounts of 3-phenyl-1-propanol, benzyl and p-hydroxybenzyl alcohols as the products of both cinnamate and phenylpyruvate pathways. CONCLUSION: The addition of HP20 resin, made it possible to direct the catabolism of L- phenylalanine to benzaldehyde, the desired target compound, and to trap it before its transformation into benzyl alcohol. In these conditions, benzaldehyde production was increased 21-fold, from 33 to 710 mg l-1 corresponding to a molar yield of 31%. SIGNIFICANCE AND IMPACT OF THE STUDY: These results showed the good potential of Trametes suaveolens as a biotechnological agent to synthesize natural benzaldehyde which is one of the most important aromatic aldehydes used in the flavour industry.


Subject(s)
Benzaldehydes/metabolism , Phenylalanine/metabolism , Polyporales/metabolism , Benzyl Alcohol , Biotechnology/methods , Biotransformation/drug effects , Food Additives , Polyporales/growth & development , Resins, Plant/metabolism
15.
EMBO J ; 20(4): 812-8, 2001 Feb 15.
Article in English | MEDLINE | ID: mdl-11179225

ABSTRACT

A transgene inserted in euchromatin exhibits mosaic expression when targeted by a fusion protein made of the DNA-binding domain of GAL4 and the heterochromatin-associated protein HP1. The silencing responds to the loss of a dose of the dominant modifiers of position-effect variegation Su(var)3-7 and Su(var)2-5, the locus encoding HP1. The genomic environs of the insertion site at 87C1 comprise the dispersed repetitive elements micropia and alphagamma. In the presence of the GAL4-HP1 chimera, the polytene chromosomes of this line form loops between the insertion site of the transgene and six other sections of chromosome 3R, as well as, rarely, with pericentric and telomeric heterochromatin. In contrast to the insertion site of the transgene at 87C, the six loop-forming sites in the euchromatic arm were each previously described as intercalary heterochromatin. Moreover, GAL4-HP1 tethering on one homologue trans-inactivates the reporter on the other. HP1, probably together with other partners, could thus facilitate the coalescence of dispersed middle repetitive sequences, and organize the heterochromatic structure responsible for the variegated silencing of nearby euchromatic genes.


Subject(s)
Chromosomal Proteins, Non-Histone/physiology , Chromosomes , Drosophila/genetics , Gene Silencing , Animals , Base Sequence , Chromobox Protein Homolog 5 , DNA Primers , Genes, Reporter , Polymerase Chain Reaction , Recombinant Fusion Proteins/metabolism , Repetitive Sequences, Nucleic Acid , Transgenes
16.
Appl Microbiol Biotechnol ; 57(5-6): 725-30, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11778885

ABSTRACT

Pycnoporus cinnabarinus MUCL39533 was shown to be able to convert p-coumaric acid into p-hydroxybenzaldehyde, a component of high organoleptic note present in natural vanilla aroma. Use of phospholipid-enriched medium led to high-density cultures of P. cinnabarinus, since dry mycelial biomass was increased three-fold as compared to glucose medium. In the presence of phospholipids, 155 mg l(-1) p-hydroxybenzaldehyde was produced as the major compound on culture day 13 with a molar yield of 26%. The degradation pathways of p-coumaric acid were investigated. Based on the different metabolites identified, an oxidative side-chain degradation pathway of p-coumaric acid conversion to p-hydroxybenzoic acid was suggested. This acid was further reduced to p-hydroxybenzaldehyde and p-hydroxybenzyl alcohol, or hydroxylated and reduced to protocatechyl derivatives. Additionally, a reductive pathway of p-coumaric acid with 3-(4-hydroxyphenyl)-propanol as the terminal product occurred.


Subject(s)
Agaricales/metabolism , Benzaldehydes/metabolism , Coumaric Acids/metabolism , Agaricales/growth & development , Benzaldehydes/chemistry , Biotechnology , Biotransformation , Coumaric Acids/chemistry , Flavoring Agents/isolation & purification , Flavoring Agents/metabolism , Kinetics , Models, Chemical , Oxidation-Reduction , Phospholipids/metabolism , Propionates
17.
J Cell Sci ; 113 Pt 23: 4253-61, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11069770

ABSTRACT

Position-effect variegation results from mosaic silencing by chromosomal rearrangements juxtaposing euchromatin genes next to pericentric heterochromatin. An increase in the amounts of the heterochromatin-associated Su(var)3-7 and HP1 proteins augments silencing. Using the yeast two-hybrid protein interaction trap system, we have isolated HP1 using Su(var)3-7 as a bait. We have then delimited three binding sites on Su(var)3-7 for HP1. On HP1, the C-terminal moiety, including the chromo shadow domain, is required for interaction. In vivo, both proteins co-localise not only in heterochromatin, but also in a limited set of sites in euchromatin and at telomeres. When delocalised to the sites bound by the protein Polycomb in euchromatin, HP1 recruits Su(var)3-7. Finally, and in contrast with euchromatin genes, a decrease in the amounts of both proteins enhances variegation of the light gene, one of the few genetic loci mapped within pericentric heterochromatin. This body of data supports a direct link between Su(var)3-7 and HP1 in the genomic silencing of position-effect variegation.


Subject(s)
Chromosomal Proteins, Non-Histone/metabolism , Drosophila Proteins , Drosophila melanogaster/genetics , Gene Silencing , Heterochromatin/metabolism , Repressor Proteins/metabolism , Alleles , Animals , Chromobox Protein Homolog 5 , Chromosomal Proteins, Non-Histone/genetics , DNA, Satellite/genetics , Euchromatin/genetics , Euchromatin/metabolism , Gene Expression/genetics , Gene Rearrangement/physiology , Heterochromatin/genetics , Mutagenesis, Insertional/physiology , Repressor Proteins/genetics , Telomere/genetics , Telomere/metabolism , Two-Hybrid System Techniques
18.
Mol Gen Genet ; 263(3): 445-54, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10821178

ABSTRACT

In Drosophila melanogaster, several factors have been suggested to influence the rates of P-element transposition and excision, including position effects, size and structure of the elements and differences in transposase source. We have investigated the effect of the size of the starting P-element on the rates of excision and transposition. Four transgenes localized at the same insertion site on the X chromosome and which differ by the number of copies of an internal repeated sequence, were studied. Transgenes with sizes ranging from 11 kb to 22 kb excise at similar rates, and size does not correlate with the differences in transposition rate between them. We also studied the behavior of double P-elements, located at the same site and arranged in various configurations: nested, contiguous or separated by a few base pairs, in the same or reverse orientation. These double P-elements display different mobilities depending on the arrangement of the two transgenes. Transposition and excision rates were also studied for an insertion bearing four transgenes in very close proximity. Our results suggest that several neighboring elements could excise together. We also propose a new model to explain the formation of all the double P-elements we describe.


Subject(s)
DNA Transposable Elements , Drosophila melanogaster/genetics , Animals , Models, Genetic , Polymerase Chain Reaction , Sequence Analysis, DNA , Transgenes/genetics
19.
Chromosoma ; 109(7): 453-9, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11151674

ABSTRACT

We have constructed a new reporter transgene, Winkelried, equipped with a synthetic binding site for the yeast GAL4 transcriptional activator. The binding site is inserted between the white and lacZ reporter genes, and is flanked by FRT sequences. These elements allow excision of the GAL4 binding site by crossing the transgenic line with an FLP recombinase producing strain. We have generated by X-ray irradiation two independent chromosomal rearrangements, Heidi and Tell, relocating Winkelried next to pericentromeric heterochromatin. These rearrangements induce variegation of both white and lacZ. Variegation of Winkelried in the rearranged transgenic lines responds to the loss and excess of doses of the dominant suppressors of position-effect variegation (PEV) Su(var)3-7 and Su(var)2-5. Winkelried therefore constitutes a unique tool to test the effect on variegation in cis of any factor fused to the GAL4 DNA binding domain. Indeed, a chimeric protein, made of the DNA binding site of GAL4 and of HP1, the modifier of PEV encoded by Su(var)2-5, is shown to enhance variegation of Heidi and Tell. Excision of the binding sites for GAL4 in the variegating rearrangements Heidi and Tell abolishes the modifier effect of the GAL4-HP1 chimera. Therefore, in the Heidi and Tell rearrangements, enhancement of position-effect variegation depends strictly both on the concentration of GAL4-HP1 and on the presence of its binding site in the vicinity of the reporter genes.


Subject(s)
DNA-Binding Proteins , Fungal Proteins/metabolism , Gene Silencing , Heterochromatin/metabolism , Nuclear Proteins , Recombinant Fusion Proteins/metabolism , Saccharomyces cerevisiae Proteins , Transcription Factors/metabolism , Base Sequence , Binding Sites , DNA Primers , Fungal Proteins/genetics , Hepatocyte Nuclear Factor 1 , Hepatocyte Nuclear Factor 1-beta , Phenotype , Transcription Factors/genetics , Transgenes
20.
Can J Microbiol ; 45(8): 653-7, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10528397

ABSTRACT

A monokaryotic strain of the white-rot fungus Pycnoporus cinnabarinus was shown to produce, in a 2-L bioreactor culture, 100 mg.L-1 benzaldehyde (bitter almond aroma) from L-phenylalanine with a productivity of 33 mg.L-1.day-1. The addition of HP20 resin, a styrene divinylbenzene copolymer highly selective for benzaldehyde, enabled an eightfold increase in the production of benzaldehyde and a twofold increase in productivity. In the presence of HP20 resin, the production of 790 mg.L-1 benzaldehyde was concomitant with the synthesis of cinnamic acid derivatives of high organoleptic notes such as cinnamaldehyde, cinnamyl alcohol, and methyl cinnamate.


Subject(s)
Basidiomycota/growth & development , Benzaldehydes/metabolism , Phenylalanine/metabolism , Adsorption , Basidiomycota/metabolism , Biomass , Bioreactors , Culture Media , Resins, Plant
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