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1.
Mol Gen Genet ; 263(4): 722-32, 2000 May.
Article in English | MEDLINE | ID: mdl-10852495

ABSTRACT

We have studied the meiotic segregation of a chromosome length polymorphism (CLP) in the yeast Saccharomyces cerevisiae. The neopolymorphism frequently observed within the smallest chromosomes (I, VI, III and IX) is not completely understood. We focused on the analysis of the structure of chromosome I in 88 segregants from a cross between YNN295 and FL100trp. Strain FL100trp is known to carry a reciprocal translocation between the left arm of chromosome III and the right arm of chromosome I. PCR and Southern hybridization analyses were performed and a method for the rapid detection of chromosome I rearrangements was developed. Seven chromosome I types were identified among the 88 segregants. We detected 22 recombination events between homologous chromosomes I and seven ectopic recombination events between FL100trp chromosome III and YNN295 chromosome I. These recombination events occurred in 20 of the 22 tetrads studied (91%). Nine tetrads (41%) showed two recombination events. This showed that homologous recombination involving polymorphic homologues or heterologous chromosomes is the main source of neopolymorphism. Only one of the seven chromosome I variants resulted from a transposition event rather than a recombination event. We demonstrated that a Tyl element had transposed within the translocated region of chromosome I, generating mutations in the 3' LTR, at the border between U5 and PBS.


Subject(s)
Chromosomes, Fungal , Polymorphism, Genetic , Recombination, Genetic , Saccharomyces cerevisiae/genetics , Terminal Repeat Sequences/genetics , Base Sequence , Chromosome Mapping , Crosses, Genetic , DNA Primers , DNA, Fungal/genetics , DNA, Fungal/isolation & purification , Electrophoresis, Gel, Pulsed-Field , Meiosis/genetics , Molecular Sequence Data , Polymerase Chain Reaction , Restriction Mapping , Saccharomyces cerevisiae/cytology , Sequence Alignment , Sequence Homology, Nucleic Acid
2.
Yeast ; 16(6): 511-22, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10790688

ABSTRACT

Modern lager brewing yeasts used in beer production are hybrid strains consisting of at least two different genomes. To obtain information on the identity of the parental strains that gave rise to industrial lager yeasts, we used two-dimensional (2-D) gel electrophoresis and analysed the proteomes of different Saccharomyces species isolated from breweries. We found that the proteome of lager brewing yeasts and of the type strains of S. carlsbergensis, S. monacensis and S. pastorianus can be interpreted as the superimposition of two elementary patterns. One originates from proteins encoded by a S. cerevisiae-like genome. The other corresponds to a divergent Saccharomyces species whose best representative is a particular S. pastorianus strain, NRRL Y-1551. A map of industrial lager brewing yeasts has been established, with the individual origin of proteins and with identification of protein spots by comparison to known S. cerevisiae proteins. This 2-D map can be accessed on the Lager Brewing Yeast Protein Map server through the World Wide Web. This study provides the first example of the use of proteome analysis for investigating taxonomic relationships between divergent yeast species.


Subject(s)
Fungal Proteins/analysis , Saccharomyces/chemistry , Amino Acid Sequence , Chromosome Mapping , Chromosomes, Fungal/genetics , Electrophoresis, Gel, Two-Dimensional , Evolution, Molecular , Genes, Fungal/genetics , Genome, Fungal , Internet , Molecular Sequence Data , Protein Isoforms/analysis , Saccharomyces/classification , Saccharomyces/genetics , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/genetics , Sequence Analysis, Protein , Sequence Homology, Amino Acid , Species Specificity
3.
J Agric Food Chem ; 47(12): 5261-6, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10606606

ABSTRACT

A fast and quantitative method was developed to detect transgenic "Maximizer" maize "event 176" (Novartis) and "Roundup Ready" soybean (Monsanto) in food by real-time quantitative PCR. The use of the ABI Prism 7700 sequence detection system allowed the determination of the amplified product accumulation through a fluorogenic probe (TaqMan). Fluorescent dyes were chosen in such a way as to coamplify total and transgenic DNA in the same tube. Using real-time quantitative PCR, 2 pg of transgenic or total DNA per gram of starting sample was detected in 3 h after DNA extraction and the relative amounts of "Maximizer" maize and "Roundup Ready" soybean in some representative food products were quantified.


Subject(s)
Glycine max/chemistry , Zea mays/chemistry , DNA/isolation & purification , DNA Primers , Genetic Engineering , Humans , Plants, Genetically Modified/chemistry , Plants, Genetically Modified/genetics , Polymerase Chain Reaction , Glycine max/genetics , Zea mays/genetics
4.
Yeast ; 14(6): 551-64, 1998 Apr 30.
Article in English | MEDLINE | ID: mdl-9605505

ABSTRACT

In order to study meiotic segregation of chromosome length polymorphism in yeast, we analysed the progeny of a cross involving two laboratory strains FL100trp and YNN295. Analysis of the parental strains led us to detect an important length polymorphism of chromosomes I and III in FL100trp. A reciprocal translocation involving 80 kb of the left arm of chromosome III and 45 kb of the right arm of chromosome I was shown to be the cause for the observed polymorphism in this strain. The characterization of the translocation breakpoints revealed the existence of a transposition hot-spot on chromosome I: the sequence of the translocation joints on chromosomes I and III suggests that the mechanism very likely involved homologous recombination between Ty2 transposable elements on each chromosome. Analysis of FL100, FL200 and FL100trp ura, which are related to FL100trp, shows that this reciprocal translocation is present in some of the strains of the FL series, whereas the parental strain FL100 does not carry the same rearrangement. We evidenced instead the duplication of 80 kb of chromosome III on chromosome I and a deletion of 45 kb of the right arm of chromosome I in this strain, indicating that secondary events might have taken place and that the strain currently named FL100 is not the common ancestor of the FL series.


Subject(s)
Chromosomes, Fungal/genetics , Polymorphism, Genetic , Saccharomyces cerevisiae/genetics , Translocation, Genetic , Base Sequence , Crosses, Genetic , DNA, Fungal/genetics , Electrophoresis, Gel, Pulsed-Field , Karyotyping , Molecular Sequence Data , Polymerase Chain Reaction , Saccharomyces cerevisiae/growth & development , Sequence Analysis, DNA , Species Specificity
5.
Appl Environ Microbiol ; 64(3): 1157-60, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9501455

ABSTRACT

A fast, sensitive, and target contaminant-modulable method was developed to detect viable bacteria, molds, and yeasts after heat treatment. By reverse transcriptase PCR with elongation factor gene (EF-Tu or EF-1 alpha)-specific primers, the detection level was 10 cells ml of milk-1. The simplicity and rapidity (4 h) of the procedure suggests that this method may be easily transposable to other foods and other contaminants.


Subject(s)
Bacteria/isolation & purification , Fungi/isolation & purification , Milk/microbiology , Polymerase Chain Reaction , Yeasts/isolation & purification , Animals , Hot Temperature , Peptide Elongation Factor Tu/genetics
6.
J Med Chem ; 38(17): 3207-16, 1995 Aug 18.
Article in English | MEDLINE | ID: mdl-7650673

ABSTRACT

A series of 3-substituted (aryloxy)silane derivatives of benzylamine (4, 4', or 4") was synthesized and evaluated for hypocholesterolemic activity. Most of the new silane derivatives were identified as potent inhibitors of pig liver squalene epoxidase with IC50 values in the submicromolar range. In vitro inhibition of cholesterol biosynthesis in Hep-G2 cells was observed with a very good potency for the ene-yne derivatives 4a, 4i, 4n, 4q, and 4u as well as for the yne-yne compound 4". In vivo, 4i, 4u, 4', and 4" were found to decrease cholesterol biosynthesis in rats upon oral administration with ED50 values in the range of 2-7 mg/kg. Therefore, these new (aryloxy)methylsilane derivatives of benzylamine represent a new class of potent squalene epoxidase inhibitors with promising hypocholesterolemic properties.


Subject(s)
Anticholesteremic Agents/pharmacology , Cholesterol/biosynthesis , Oxygenases/antagonists & inhibitors , Silanes/pharmacology , Animals , Anticholesteremic Agents/chemical synthesis , Anticholesteremic Agents/chemistry , Humans , Liver/enzymology , Magnetic Resonance Spectroscopy , Rats , Silanes/chemical synthesis , Silanes/chemistry , Squalene Monooxygenase , Swine
7.
Tohoku J Exp Med ; 146(4): 379-83, 1985 Aug.
Article in English | MEDLINE | ID: mdl-3000023

ABSTRACT

Mothers of offspring Balb/c mice were stimulated after birth by two substances, a bacterial lysate (LAB) and a chemical, diethyldithiocarbamate (DETC). Anti-sheep red blood cell (SRBC) antibodies were studied after immunization of stimulated mothers or offspring. An increase of anti-SRBC was observed in LAB-stimulated mothers, but these antibodies were decreased in their offspring before weaning. Sometimes, these antibodies were increased in LAB-stimulated newborn mice. DETC stimulation of mothers induced an elevation of antibody response in mothers and newborns. The same results were obtained in previous investigations where the pregnant mother was stimulated with the same agents.


Subject(s)
Animals, Newborn/immunology , Bacteria , Cell Extracts , Immunization , Adjuvants, Immunologic/pharmacology , Animals , Antibodies/analysis , Ditiocarb/pharmacology , Erythrocytes/immunology , Female , Male , Mice , Mice, Inbred BALB C , Pregnancy , Sheep/immunology
9.
C R Seances Acad Sci III ; 296(1): 15-8, 1983 Jan 10.
Article in French | MEDLINE | ID: mdl-6404506

ABSTRACT

Pregnant Mice were stimulated with two substances, an antibronchitic lysate (LAB) and diethyldithiocarbamate (DTC). PFC response was studied in mothers and their offspring for 6 weeks after birth. An increase in PFC response was noted in the immunostimulated adult Mice. In the newborn Mice, the number of PFC increased between the 1st and 6th week. In comparison with controls, PFC response appeared later in the newborns to LAB-stimulated mothers and earlier in those to DTC-stimulated mothers.


Subject(s)
Adjuvants, Immunologic/pharmacology , Immunity, Maternally-Acquired , Animals , Animals, Newborn , Female , Immunologic Techniques , Maternal-Fetal Exchange , Mice , Mice, Inbred BALB C , Pregnancy
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