Der Gröditzberg : Romantische Erzählung

von Carl Wilhelm Peschel

Das große Loos : Posse in einem Akte

von Bartholmä

Der Räuber im Kaukasus : eine Erzählung

von Alexander Marlinski ; deutsch von S. Rügeisen

Coupling between protein folding and allostery in the GroE chaperonin system

GroEL is an allosteric protein that facilitates protein folding in an ATP-dependent manner. Herein, the relationship between cooperative ATP binding by GroEL and the kinetics of GroE-assisted folding of two substrates with different GroES dependence, mouse dihydrofolate reductase (mDHFR) and mitochondrial malate dehydrogenase, is examined by using cooperativity mutants of GroEL. Strong intra-ring positive cooperativity in ATP binding by GroEL decreases the rate of GroEL-assisted mDHFR folding owing to a slow rate of the ATP-induced transition from the protein-acceptor state to the protein-release state. Inter-ring negative cooperativity in ATP binding by GroEL is found to affect the kinetic partitioning of mDHFR, but not of mitochondrial malate dehydrogenase, between folding in solution and folding in the cavity underneath GroES. Our results show that protein folding by this “two-stroke motor” is coupled to cooperative ATP binding.

Minimal and optimal mechanisms for GroE-mediated protein folding

We have analyzed the effects of different components of the GroE chaperonin system on protein folding by using a nonpermissive substrate (i.e., one that has very low spontaneous refolding yield) for which rate data can be acquired. In the absence of GroES and nucleotides, the rate of GroEL-mediated refolding of heat- and DTT-denatured mitochondrial malate dehydrogenase was extremely low, but some three times higher than the spontaneous rate. This GroEL-mediated rate was increased 17-fold by saturating concentrations of ATP, 11-fold by ADP and GroES, and 465-fold by ATP and GroES. Optimal refolding activity was observed when the dissociation of GroES from the chaperonin complex was dramatically reduced. Although GroEL minichaperones were able to bind denatured mitochondrial malate dehydrogenase, they were ineffective in enhancing the refolding rate. The spectrum of mechanisms for GroE-mediated protein folding depends on the nature of the substrate. The minimal mechanism for permissive substrates (i.e., having significant yields of spontaneous refolding), requires only binding to the apical domain of GroEL. Slow folding rates of nonpermissive substrates are limited by the transitions between high- and low-affinity states of GroEL alone. The optimal mechanism, which requires holoGroEL, physiological amounts of GroES, and ATP hydrolysis, is necessary for the chaperonin-mediated folding of nonpermissive substrates at physiologically relevant rates under conditions in which retention of bound GroES prevents the premature release of aggregation-prone folding intermediates from the chaperonin complex. The different mechanisms are described in terms of the structural features of mini- and holo-chaperones.

Die sanfte, Eine phantastische Erzählung.

"16. bis 25. tausend."

Geschichte von Sul und Schumul, unbekannte erzählung aus Tausend und einer nacht,

Text and added title-page in Arabic.

Krummstiebels Heldentaten : erzählung aus der Studienzeit eines Technikers /

Table of contents on verso of p. 111.

Robinson Crusoe, nach der Defoe'schen erzählung für die jugend bearbeitet

Contains pt. 1 only.

Der schwarze Robinson Abenteuer eines negerknaben auf den Südsee-inseln. : Eine erzählung für die reisere jugend /

For a discussion of the possible relationship between this work and Séguin's Le Robinson noir, cf. H. Ullrich, Zur bibliographie der Robinsonaden (In Zeitschrift für bücherfreunde, jahrg.XI, hft. 12, p.495

Unter dem französischen joche. Geschichtliche erzählung aus der zeit von 1806-1812.

Mode of access: Internet.

Kampfe um Deutschlands freiheit. Geschichtliche erzählung aus der zeit von 1813-1815.

Mode of access: Internet.

Irrlichter : eine Erzählung /

Mode of access: Internet.