scholarly journals MITOCHONDRIAL GENETICS. VI THE PETITE MUTATION IN SACCHAROMYCES CEREVISIAE: INTERRELATIONS BETWEEN THE LOSS OF THE ρ+ FACTOR AND THE LOSS OF THE DRUG RESISTANCE MITOCHONDRIAL GENETIC MARKERS

Genetics ◽  
1974 ◽  
Vol 76 (2) ◽  
pp. 195-219
Author(s):  
J Deutsch ◽  
B Dujon ◽  
P Netter ◽  
E Petrochilo ◽  
P P Slonimski ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Drug Resistance ◽  
Mitochondrial Genome ◽  
Genetic Marker ◽  
Genetic Markers ◽  
The Other ◽  
Mitochondrial Genetics ◽  
Petite Mutation ◽  
Target Theory

ABSTRACT The survival of the ρ+ factor and of DrugR mitochondrial genetic markers after exposure to ethidium bromide has been studied. A technique allowing the determination of DrugR genetic markers among a great number of both grande and petite colonies has been developed. The results have been analyzed by the target theory. The survival of the ρ+ factor is always less than the survival of any DrugR genetic marker. The survivals of CR and ER are similar to each other, while that of OR is greater than that of the other two DrugR markers. All possible combinations of DrugR markers have been found among the ρ- petite cells induced, while the only type found among the grande colonies is the preexisting one. The loss of the CR and ER genetic markers was found to be the most frequently concomitant, while the correlation between the loss of the OR marker and the other two DrugR markers is less strong. Similar results have been obtained after U.V. irradiation. Interpretations concerning the structure of the yeast mitochondrial genome are given and hypotheses on the mechanism of petite mutation discussed.

scholarly journals Oxygen and haem regulate the synthesis of peroxisomal proteins: catalase A, acyl-CoA oxidase and Pex1p in the yeast Saccharomyces cerevisiae; the regulation of these proteins by oxygen is not mediated by haem

2000 ◽  
Vol 350 (1) ◽  
pp. 313-319 ◽  
Author(s):  
Marek SKONECZNY ◽  
Joanna RYTKA
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mitochondrial Genome ◽  
Oxygen Sensor ◽  
Transcriptional Factor ◽  
The Other ◽  
Wild Type ◽  
Yeast Saccharomyces Cerevisiae ◽  
Regulatory Factors ◽  
Genes Encoding ◽  
Acyl Coa Oxidase

Saccharomyces cerevisiae genes related to respiration are typically controlled by oxygen and haem. Usually the regulation by these factors is co-ordinated; haem is indicated as the oxygen sensor. However, the responsiveness of peroxisome functions to these regulatory factors is poorly understood. The expression of CTA1, POX1 and PEX1 genes encoding the peroxisomal proteins catalase A, acyl-CoA oxidase and Pex1p peroxin respectively was studied under various conditions: in anaerobiosis, in the absence of haem and in respiratory incompetence caused by the lack of a mitochondrial genome (ρ0). The influence of haem deficiency or ρ0 on peroxisomal morphology was also investigated. Respiratory incompetence has no effect on the expression of CTA1 and POX1, whereas in the absence of haem their expression is markedly decreased. The synthesis of Pex1p is decreased in ρ0 cells and is decreased even more in haem-deficient cells. Nevertheless, peroxisomal morphology in both these types of cell does not differ significantly from the morphology of peroxisomes in wild-type cells. The down-regulating effect of anoxia on the expression of CTA1 and POX1 is even stronger than the effect of haem deficiency and is not reversed by the addition of exogenous haem or the presence of endogenous haem. Moreover, neither of these genes responds to the known haem-controlled transcriptional factor Hap1p. In contrast with the other two genes studied, PEX1 is up-regulated in anaerobiosis. The existence of one or more novel mechanisms of regulation of peroxisomal genes by haem and oxygen, different from those already known in S. cerevisiae, is postulated.

scholarly journals Two Novel Techniques for Determination of Polysaccharide Cross-Links Show that Crh1p and Crh2p Attach Chitin to both β(1-6)- and β(1-3)Glucan in the Saccharomyces cerevisiae Cell Wall

2009 ◽  
Vol 8 (11) ◽  
pp. 1626-1636 ◽  
Author(s):  
Enrico Cabib
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Wall ◽  
Acetic Acid ◽  
Yeast Cell ◽  
Cell Walls ◽  
Double Mutant ◽  
The Other ◽  
Cross Links

ABSTRACT Previous work, using solubilization of yeast cell walls by carboxymethylation, before or after digestion with β(1-3)- or β(1-6)glucanase, followed by size chromatography, showed that the transglycosylases Crh1p and Crh2p/Utr2p were redundantly required for the attachment of chitin to β(1-6)glucan. With this technique, crh1Δ crh2Δ mutants still appeared to contain a substantial percentage of chitin linked to β(1-3)glucan. Two novel procedures have now been developed for the analysis of polysaccharide cross-links in the cell wall. One is based on the affinity of curdlan, a β(1-3)glucan, for β(1-3)glucan chains in carboxymethylated cell walls. The other consists of in situ deacetylation of cell wall chitin, generating chitosan, which can be extracted with acetic acid, either directly (free chitosan) or after digestion with different glucanases (bound chitosan). Both methodologies indicated that all of the chitin in crh1Δ crh2Δ strains is free. Reexamination of the previously used procedure revealed that the β(1-3)glucanase preparation used (zymolyase) is contaminated with a small amount of endochitinase, which caused erroneous results with the double mutant. After removing the chitinase from the zymolyase, all three procedures gave coincident results. Therefore, Crh1p and Crh2p catalyze the transfer of chitin to both β(1-3)- and β(1-6)glucan, and the biosynthetic mechanism for all chitin cross-links in the cell wall has been established.

scholarly journals RAPD and ISSR analyses of Saccharomyces cerevisiae isolates from different sources

2018 ◽  
Vol 12 (2) ◽  
pp. 40-50
Author(s):  
Sawas Younus Hammadi ◽  
Anmar Sael Hussein ◽  
Duha Mysire Majeed ◽  
Batol I. Dheeb ◽  
Eman Noaman Ismail
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Genetic Distance ◽  
Genetic Markers ◽  
The Other ◽  
Natural Sources ◽  
Rapd And Issr ◽  
Different Sources ◽  
Isolated Species

     The purpose of this study was to isolate the Saccharomyces cerevisiae present on different fruits and performing RAPD and ISSR analyses to know the genetic interrelationship between different S. cerevisiae isolates. Some fruits namely apple, plum, dates, and peach were used as natural sources for S. cerevisiae isolation. The isolated S. cerevisiae was designated as SUC1, SUC2, SUC3, SUC4, SUC5 respectively. Amplicon fingerprints for the isolated species were obtained by RAPD assay using six different primers and ISSR assay using six different primers. RAPD assay showed the lowest genetic distance (0.1559) between SUC2 and SUC3 isolates whereas ISSR assay showed the lowest genetic distance (0.06899) between SUC4 and SUC5 isolates.  Both genetic markers showed the highest genetic distance for SUC1 when compared to the other isolates.

scholarly journals COMPARATIVE ANALYSIS OF THE EFFICIENCY OF MODERN METHODS FOR DETERMINATION OF YOUNG DUCKS SEX

2019 ◽  
Vol 57 ◽  
pp. 175-184
Author(s):  
Yu. V. Bondarenko ◽  
М. I. Shkurko
Keyword(s):  
Comparative Analysis ◽  
Sexual Dimorphism ◽  
Genetic Markers ◽  
The Other ◽  
Specific Method ◽  
Domestic Duck ◽  
Modern Methods ◽  
Experimental Researches ◽  
Interspecies Hybrid

Experimental researches were carried out during the years 2012–2017 at the farm "Povit-Agro", Bila Tserkva region, Kyiv Oblast, as well as at other farms. 1390 Ukrainian mulards were bred during these 2 years. Throughout our researches the French mulard was presented with 2425 1-day-old hybrid ducklings. In addition, during the studies, the 1-day-old ducklings of different breeds were assessed, namely ducklings of a domestic duck – 7579 heads, ducklings of a musk duck – 1685 heads. A comparative analysis of the effeciency of modern methods for determining the sex of young ducks of two species and of interspecies hybrid is conducted. It has been found that the highest accuracy of duckling sex determination (100%) of all genotypes is provided by the universal Japanese method (ventsexing), and a specific method - colorsexing (based on genetic markers of down coloring). Sidorov's method (probing of resonator of males) allows to determine the sex of domestic (but not musk) and mullard ducklings with an accuracy of 94–98% at a sorting rate of 300 g/h. The anatomical method is absolutely accurate, but it is associated with young ducks slaughtering. Morphosexing is effective for ducklings of all studied genotypes starting from the 2-month age . Morphosexing is effective for ducklings starting from the 2-month old of all studied genotypes. Beginning from 60 days old, the sex of ducklings of a musk duck, as well as mulards, can be determined due to the color and size of skin folds around the upper part of the beak with an accuracy of 97–99%. For the 2-month old ducklings of a domestic duck, sexual dimorphism is clearly expressed according to the other two features. Males at this age already have two twisted feathers in their tails, and females, unlike males, can quack loudly.

scholarly journals Meiotic disjunction in mouse translocations and the determination of centromere position

1971 ◽  
Vol 18 (2) ◽  
pp. 215-235 ◽  
Author(s):  
A. G. Searle ◽  
C. E. Ford ◽  
C. V. Beechey
Keyword(s):  
Linkage Group ◽  
Genetic Marker ◽  
Reciprocal Translocation ◽  
The Other ◽  
Group V ◽  
Expected Frequency ◽  
Centromere Position ◽  
Lower Frequencies

SUMMARYIf heterozygotes for a reciprocal translocation are intercrossed, some of their viable balanced progeny result from the fusion of unbalanced gametes with complementary duplications and deficiencies of the translocated segments. Therefore, if one parent in such an intercross is homozygous for a genetic marker on one of the segments concerned, some homozygous offspring will be produced even if the other parent does not have the marker. The expected frequency of such exceptional offspring among live-born is one-sixth if the marker is on the distal (non-centromeric) side of the point of exchange and single chiasmata normally occur in each interstitial segment. Much lower frequencies are expected if the marker is on the centromeric side, since duplications and deficiencies of proximal segments occur only as a consequence of adjacent-2 disjunction, in which homologous centromeres proceed to the same pole. This is rarer than normal disjunction. Thus, by comparing the frequencies of offspring homozygous for markers on one or other side of the point of exchange, it is possible (i) to determine which marker is in the centromeric segment, (ii) to estimate the frequency of adjacent-2 disjunction, given information on the nature of meiotic configurations in the translocation concerned.By this method, it is shown that the frequency of adjacent-2 disjunction is similar in heterozygotes for mouse translocations (T5;18)26H, T(13; ?) 70H and T(14;17)264Ca, averaging 13%. Centromeres were located at the Sd end of linkage group V (confirming previous findings), the fz end of XIII and the bg end of XIV.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 330-331
Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose
Keyword(s):  
High Order ◽  
Simulation Technique ◽  
The Other ◽  
Image Simulation ◽  
Diffraction Vector ◽  
Burgers Vector ◽  
Weak Beam ◽  
Beam Image ◽  
Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

Procedures for the Quantitative Determination of Autoprothrombin C

1962 ◽  
Vol 08 (03) ◽  
pp. 434-441 ◽  
Author(s):  
Edmond R Cole ◽  
Ewa Marciniak ◽  
Walter H Seegers
Keyword(s):  
Quantitative Determination ◽  
Plasma Sample ◽  
Quantitative Measure ◽  
The Other ◽  
Clotting Time ◽  
Bovine Plasma ◽  
Autoprothrombin C

SummaryTwo quantitative procedures for autoprothrombin C are described. In one of these purified prothrombin is used as a substrate, and the activity of autoprothrombin C can be measured even if thrombin is in the preparation. In this procedure a reaction mixture is used wherein the thrombin titer which develops in 20 minutes is proportional to the autoprothrombin C in the reaction mixture. A unit is defined as the amount which will generate 70 units of thrombin in the standardized reaction mixture. In the other method thrombin interferes with the result, because a standard bovine plasma sample is recalcified and the clotting time is noted. Autoprothrombin C shortens the clotting time, and the extent of this is a quantitative measure of autoprothrombin C activity.

Determination of Factor XIII Activity and of Factor XIII Inhibitors Using an Ammonium-Sensitive Electrode

1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Xiii ◽  
Normal Subjects ◽  
The Other ◽  
Activity Measurement ◽  
Factor Xiii Deficiency ◽  
Assay Procedure ◽  
Stabilization Factor ◽  
Release Method ◽  
Sensitive Electrode

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.

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