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131.
1. The effects of ATP, PP(i) and EDTA on the skeletal-muscle pyruvate kinase reaction at various concentrations of magnesium (where ;magnesium' refers to total Mg(2+), both free and in the form of complexes) were investigated. The reaction rate was determined as the amount of pyruvate formed in a recorded time of incubation. 2. At 44mm-magnesium the K(m) values for ADP and phosphoenolpyruvate were unaltered by the presence of ATP up to 6.8mm in systems buffered with either tris-hydrochloric acid or glycylglycine-sodium hydroxide, but the K(m) values were different in these systems. The K(m) for one substrate was independent of the concentration of the second substrate. 3. At 10mm-magnesium in the tris-hydrochloric acid system ATP inhibited the reaction competitively with respect to ADP and phosphoenolpyruvate. In the glycylglycine-sodium hydroxide system the inhibition appeared to be non-competitive. At 10mm-magnesium the K(m) values were lower than at 44mm-magnesium and dependent on the system used. 4. In the tris-hydrochloric acid system the reaction rate rose with increasing magnesium concentration up to a maximum at a concentration 10-20 times that of ADP. Further increase inhibited the reaction and at 44mm-magnesium the rate was 25-50% of its maximum. This inhibition paralleled that produced by increasing trimethylammonium chloride concentrations and was not due to a specific effect of the Mg(2+) ion. 5. In the presence of 6.8mm-ATP no reaction occurred below 4-6mm-magnesium, and further increase apparently abolished the inhibition as the reaction rate increased and became equal to those obtained in the absence of ATP at 10-25mm-magnesium. Further increase in magnesium concentration gave reaction rates that were slightly higher in the presence of ATP than in its absence. The maximal rate in the presence of ATP was distinctly lower than in its absence. When 6.8mm-PP(i) or 6.8mm-EDTA was present the variations in reaction rate with rising magnesium concentration were similar to that obtained in the presence of ATP below 6-8mm-magnesium but further increase in the magnesium concentration resulted in an increase in the rate up to a maximum comparable with that of the control. The effect of pure chelation was thus a displacement of the reaction maximum to higher magnesium concentrations without changing the maximal rate. When correction had been made for this effect, ATP gave inhibition at 44mm-magnesium that was competitive with respect to ADP (K(i) 2.1x10(-2)m). This degree of inhibition is far less than was reported earlier and its importance for the mechanism of the pyruvate kinase reaction is discussed.  相似文献   
132.
Zusammenfassung Bei einem Patienten mit multiplen Mißbildungen wurde eine Duplikation für die distale Hälfte vom kurzen Arm des Chromosoms 2 und eine Defizienz an einem C-Chromosom gefunden. In der Literatur sind vier Fälle mit ähnlicher Duplikation, jedoch jeweils einer klein n Defizienz am Chromosom 3 beschrieben worden. Ein Vergleich der klinischen Merkmale bei den fünf Patienten zeigt weitgehende Übereinstimmungen. Es wird gefolgert, daß die gleichartige Duplikation für das einheitliche klinische Bild der Patienten verantwortlich ist. Es wurden Chromosomenmessungen, Analysen der Replikationsmuster und Meioseuntersuchungen durchgeführt. Die Genloci für das Ss- und das Rh-System konnten von einer Lokalisierung auf dem duplizierten Segment ausgeschlossen werden.
2/C translocation in father and daughter: 46,XY t (2p-;Cp+) and 46,XX Cp+
Summary In a patient with multiple anomalies, a duplication comprising the distal half of the short arm of chromosome 2 and a small deficiency of a C-chromosome was found. Four other cases from the literature exhibit a similar duplication combined with a small deficiency each of chromosome 3. Comparison of the clinical pictures of the five patients revealed a conformity in the major features. It is concluded that the duplication is responsible for the uniform appearance of these patients. The studies performed include chromosome measurements, examination of replication patterns and meiosis. The gene loci for the Ss and Rh systems could be excluded from localization on the duplicated segment.


Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   
133.
U. Wolf  J. Klose  G. Oser 《Human genetics》1969,8(2):137-141
Zusammenfassung Kanarienvogel (Serinus) und Stieglitz (Carduelis) zeigen für das Enzym Glucose-6-Phosphat-Dehydrogenase in der Stärkegelektrophorese jeweils nur eine Bande, die aber verschiedene Positionen einnehmen. Interspecieshybriden beider Geschlechter wurden aus der natürlichen Kreuzung Kanarienvogel (f)xStieglitz (m) erhalten; die Identifizierung des Geschlechts der äußerlich ähnlichen Hybriden erfolgte durch Chromosomenanalyse. Die Hybriden zeigen in beiden Geschlechtern ein identisches Elektrophoresemuster, das die gleiche Zone umfaßt wie bei dem in vitro-Gemisch aus Gewebehomogenaten der Ausgangsarten. Entsprechende Befunde liefert die Analyse der 6-Phosphogluconatdehydrogenase. Hieraus ist zu schließen, daß beide Enzyme von autosomalen Genen determiniert werden.
Autosomal determination of glucose-6-phosphate dehydrogenase in birdsStudies on interspecific hybrids of serinus and carduelis (family: Fringillidae)
Summary The electrophoretic mobility of the single G-6-PD-band in Serinus and Carduelis is different. The natural cross Serinus (f)xCarduelis (m) results in viable hybrids of both sexes, as confirmed by chromosome analysis. The isoenzymes of G-6-PD are indentical in both sexes of the hybrids, exhibiting a broad diffuse pattern comprising the same zone as obtained from an in vitro mixture of parental homogenates. Related findings are reported on the enzyme 6-PGD. It is concluded that both enzymes are autosomally determined in these species.


Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.

Wesentliche Teile dieser Arbeit werden von Herrn G. Oser als Dissertation der Medizinischen Fakultät der Universität Freiburg i. Br. vorgelegt.  相似文献   
134.
Measles vaccines were prepared from the same virus fluids by inactivation with formaldehyde or by extraction with ether, ethyl acetate, or Freon 113 in the presence of Tween 80. Tests of antigenic potency, based on antibody levels in guinea pigs, showed that the formaldehyde-inactivated vaccines were more potent than the solvent-inactivated preparations and had the additional advantage of long shelf life. Residual Tween 80 in the solvent-extracted vaccines resulted in marked loss of immunogenic potency without significant loss of hemagglutinating activity. Neither extraction with organic solvents nor exhaustive dialysis efficiently removed Tween 80 from aqueous solutions.  相似文献   
135.
In a mutation experiment with a rough, ampicillin-resistant strain, we isolated two smooth mutants which were both sensitive to ampicillin and carried defects in the cell envelope. One of the strains (with the envA gene) is hindered in its completion of septa and forms chains of cells. The envA gene has been mapped to a position between leu and proB, at 2 to 4 min. The envA gene decreased the resistance mediated by both episomal and chromosomal genes for resistance to several antibiotics. During growth the envA mutant was characterized by abnormal ratios between viable count or cell count and optical density. The ratio between viable count and optical density was affected during shift-up and shift-down experiments. When compared to the parent strain, the envA mutant was found to be more resistant to ultraviolet irradiation on plates. Prestarvation for tryptophan had a protective effect against irradiation both on the parent strain and the envA mutant.  相似文献   
136.
Zusammenfassung Die elektrophoretische Analyse der Isoenzyme der Sorbitdehydrogenase (SDH) bei verschiedenen Säugerspecies unter Einschluß des Menschen läßt darauf schließen, daß bei Säugern nur 1 Genlocus für dieses Enzym existiert. Auch bei Knochenfischen läßt sich in der Regel nur 1 SDH-Gen nachweisen. Eine Ausnahme bilden einige Species der Fischordnung Isospondyli. Innerhalb dieser Ordnung findet sich eine Diploid-tetraploid-Beziehung. Arten mit diploiden Charakteristika wie der Hering (Clupea harengus) besitzen 1 SDH-locus, an dem 3 Allele zu beobachten waren. Bei einigen phylogenetisch tetraploiden lachsartigen Fischen läßt sich eine Duplikation des SDH-Gens nachweisen. Während bei der Bachforelle (Salmo trutta) die nach der Tetraploidisierung zunächst identischen loci sich divergent entwickelt haben und jetzt diploidisiert sind, zeigen Regenbogenforelle (Salmo irideus) und Blaufelchen (Coregonus lavaretus) tetrasome Phänotypen der SDH. Beim Blaufelchen findet sich ein Überschuß an Heterozygoten, der auf eine meiotische Vorzugspaarung der Chromosomen mit identischen Allelen schließen läßt. Diese Befunde geben Einblick in den Mechanismus der Diploidisierung, der in der Evolution der höheren Wirbeltiere eine wesentliche Rolle gespielt haben dürfte.
Sorbitol dehydrogenase isozymes in clupeoid fish: a further example of gene duplication through polyploid evolution
Summary Electrophoretic analysis of the sorbitol dehydrogenase isozymes (SDH) in various mammalian species including man revealed the existence of only 1 gene locus for this enzyme. As a rule, the same is true for Teleostean fishes. Some species of the fish order Isospondyli, however, represent an exception. Within this order, a diploid-tetraploid relationship exists. Species exhibiting diploid characteristics as the herring (Clupea harengus), are endowed with a single SDH gene locus at which 3 different alleles were observed. In some Salmonoid fish having passed through tetraploid evolution, a duplication of the SDH gene can be demonstrated. While in Salmo trutta the duplicated genes evolved divergently and became diploidized, in Salmo irideus and Coregonus lavaretus tetrasomic phenotypes occur. In Coregonus, the predominance of heterozygotes is to be interpreted as the consequence of preferential pairing of meiotic chromosomes endowed with identical alleles. These findings give some insight in the diploidization mechanism which may have played an important role during evolution of higher vertebrates.


Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   
137.
Zusammenfassung 19 Patienten, die nach einer Nierentransplantation mit Imuran behandelt wurden, wiesen eine erhöhte Anzahl Chromosomenabnormitäten im Vergleich zu 30 gesunden Kontrollpersonen der gleichen Altersklasse auf. Keine signifikant erhöhte Anzahl an Chromosomenabnormitäten fand sich jedoch bei 7 Patienten, die vor und unter der Imuran-behandlung untersucht wurden. Es wird vermutet, daß die Chromosomenabnormitäten bei den 19 mit Imuran behandelten Patienten wahrscheinlich nicht durch Imuran, sondern durch die Urämie entstanden sind.
Summary 19 patients treated with Imuran after a renal transplantation showed a high frequency of chromosome abnormalities, compared with 30 healthy control persons in the same age range. No significantly higher frequency of chromosome abnormalities was, however, found in 7 patients examined before and during treatment with Imuran. It is suggested that the chromosome abnormalities found in the 19 patients treated with Imuran were probably not due to Imuran but to Uremia.
  相似文献   
138.
Microbiological studies were made of certain Indonesian foodstuffs obtained from Malang, Surakarta, and Djakarta.Saccharomyces cerevisiae andCandida solani were isolated from ragi-roti (a baker's yeast preparation). From ragi-tempe and tempe were isolatedRhizopus oryzae, R. arrhizus, R. oligosporus, R. stolonifer, Mucor Rouxii, M. javanicus andTrichosporon pullulans. The microbiological flora of ragi-tape was found to includeCandida parapsilosis, C. melinii, C. lactosa sp. nov.,Hansenula subpelliculosa, H. anomala, H. malanga sp. nov.,Chlamydomucor oryzae andAspergillus oryzae. From ragi-ketjap, used to prepare soysauce, were isolatedRhizopus oligosporus, R. arrhizus, Aspergillus oryzae, andA. flavus, the latter species probably being an accidental contaminant. Two new species are described:Candida lactosa andHansenula malanga, from ragi-tape from Surakarta and Malang, respectively.From a thesis presented to the Graduate School of Vanderbilt University in partial fulfillment of the requirements for the Ph.D. degree, August, 1969.Financial support of Dakimah Dwidjoseputro by the Ford Foundation is grate-fully acknowledged.  相似文献   
139.
Total skin collagen is greatly increased in women with hirsuties. This is presumably due to androgen, whether locally produced or circulating.  相似文献   
140.
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