Synthesis of cytochrome oxidase components in isolated mitochondria of Neurospora crassa

The formation of polypeptides within the mitochondrion has been documented by a large body of evidence. The ability of isolated mitochondria to incorporate amino acids int

Preparation of Neurospora crassa mitochondria

The fungus Neurospora crassa represents a eukaryotic cell with high biosynthetic activities. Cell mass doubles in 2-4 hr during expone ntial growth , even in simple salt media with sucrose as the sole carbon source. The microorgani sm forms a mycelium of long hyphae durlng vegetative growth . The mitochondria can be isolated under relatively gentle condi tions since a few breaks in the threadlike hyphae are sufficient to cause the outflow of the organelles. This article describes two methods for the physical disruption of the hyphae : (I) The cell s are opened in a grind mill between two rotating corundum di sks. This is a continuous and fast procedure and allows large- and small-scale preparations of mitochondria. (2) Hyphae are ground with sand in a mortar and pestle. This procedure can be applied to microscale preparations of mitochondria starting with minute amounts of cells. Other procedures for the isolation of Neurospora mitochondria after the physical di sruption or the enzymatic degradation of the cell wall have been described elsewher

Gummihandschuhe in der chirurgischen Praxis

Die Desinfektion der Hände des Arztes ist ein noch ungelöstes Problem, trotz aller praktischen Erfolge der Chirurgie unserer Tage, die das Gegentheil zu beweisen scheinen. Wir sind noch nicht im Stande, unsere Hände so zu desinficiren, dass die Desinfektion unter allen Umständen einer strengen experimentellen Kritik Stand hält. Das lehren uns die Versuche Kümmell's, Fürbringer's, Sänger's, Reinecke's, das zeigten uns die Demonstrationen v. Bergmann's auf dem vorletzten internationalen Kongress und die neueren Untersuchungen Lauenstein's und Anderer. Eine relative Keimfreiheit können wir erhalten, eine absolute nicht, und immer wieder müssen wir mit dem schwankenden Faktor rechnen, dass das Körpergewebe des Operirten in letzter Instanz mit seinen vitalen Eigenschaften den allerdings meist nicht großen Fehler in der Desinfektion unserer Hände korrigirt. Wir erreichen damit im Allgemeinen, was wir brauchen. Wir erreichen diese relative, aber genügende Keimfreiheit der Hände jedoch nicht mehr, wenn wir infektiöses Material berührt, unsere Hände in Koth oder Eiter getaucht haben. ..

Two-dimensional potential flow past a smooth wall with partly constant curvature

The speed of a two-dimensional flow potential flow past a smooth wall, which evinces a finite curvature jump at a certain point and approximates to two arcs in the surrounding area, has a vertical tangent of inflection in the critical point as a function of the arc length of the boundary curve. This report looks at a general theorem of the local character of the conformal function at the critical point as well as the case of the finite curvature jump

Rapid enzymatic test for phenotypic HIV protease drug resistance

A phenotypic resistance test based on recombinant expression of the active HIV protease in E. coli from patient blood samples was developed. The protease is purified in a rapid onestep procedure as active enzyme and tested for inhibition by five selected synthetic inhibitors (amprenavir, indinavir, nelfinavir, ritonavir, and saquinavir) used presently for chemotherapy of HIVinfected patients. The HPLC system used in a previous approach was replaced by a continuous fluorogenic assay suitable for highthroughput screening on microtiter plates. This reduces significantly the total assay time and allows the determination of inhibition constants (K-i). The Michaelis constant (K-m) and the inhibition constant (K-i) of recombinant wildtype protease agree well with published data for cloned HIV protease. The enzymatic test was evaluated with recombinant HIV protease derived from eight HIVpositive patients scored from sensitive to highly resistant according to mutations detected by genotypic analysis. The measured K-i values correlate well with the genotypic resistance scores, but allow a higher degree of differentiation. The noninfectious assay enables a more rapid yet sensitive detection of HIV protease resistance than other phenotypic assays

Triaxiality and the determination of the cubic shape parameter K3 from five observables

The absolute and the relative quadrupole shape invariants q3 and K3 provide a model independent measure of triaxiality for beta-rigid nuclei. We will show that one can obtain q3 and K3 from a small number of observables. The approximations which are made will be shown to hold within a few percent both in the rigid triaxial rotor model and the interacting boson model. The shape parameter K3 is given for an exemplary set of nuclei and is translated into effective values of the geometrical deformation parameters beta and gamma.Comment: 16 pages, 4 figure