Publications by authors named "Ketterer P"

Article Synopsis
  • Researchers successfully used a cell-free protein synthesis (CFPS) system derived from tobacco to recreate the teleocidin biosynthetic pathway, yielding significant production levels of teleocidin B-3.
  • They discovered a key interaction between two proteins, TleA and MbtH, which played a role in this biosynthesis.
  • Additionally, they developed a method for producing UK-2 diol, a precursor to the valuable UK-2A compound, by reconstructing a complex pathway with ten proteins in a wheat germ CFPS system, showcasing the potential of plant CFPS systems for biosynthetic research.
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The nuclear pore complex (NPC) is the gatekeeper for nuclear transport in eukaryotic cells. A key component of the NPC is the central shaft lined with intrinsically disordered proteins (IDPs) known as FG-Nups, which control the selective molecular traffic. Here, we present an approach to realize artificial NPC mimics that allows controlling the type and copy number of FG-Nups.

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DNA origami has attracted substantial attention since its invention ten years ago, due to the seemingly infinite possibilities that it affords for creating customized nanoscale objects. Although the basic concept of DNA origami is easy to understand, using custom DNA origami in practical applications requires detailed know-how for designing and producing the particles with sufficient quality and for preparing them at appropriate concentrations with the necessary degree of purity in custom environments. Such know-how is not readily available for newcomers to the field, thus slowing down the rate at which new applications outside the field of DNA nanotechnology may emerge.

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Revealing the energy landscape for nucleosome association may contribute to the understanding of higher-order chromatin structures and their impact on genome regulation. We accomplish this in a direct measurement by integrating two nucleosomes into a DNA origami-based force spectrometer, which enabled subnanometer-resolution measurements of nucleosome-nucleosome distance frequencies via single-particle electron microscopy imaging. From the data, we derived the Boltzmann-weighted distance-dependent energy landscape for nucleosome pair interactions.

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We establish a DNA origami based tool for quantifying conformational equilibria of biomolecular assemblies as a function of environmental conditions. As first application, we employed the tool to study the salt-induced disassembly of nucleosome core particles. To extract binding constants and energetic penalties, we integrated nucleosomes in the spectrometer such that unwrapping of the nucleosomal template DNA, leading from bent to more extended states was directly coupled to the conformation of the spectrometer.

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We report a nanoscale rotary mechanism that reproduces some of the dynamic properties of biological rotary motors in the absence of an energy source, such as random walks on a circle with dwells at docking sites. Our mechanism is built modularly from tight-fitting components that were self-assembled using multilayer DNA origami. The apparatus has greater structural complexity than previous mechanically interlocked objects and features a well-defined angular degree of freedom without restricting the range of rotation.

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Arrays of regularly spaced nucleosomes are a hallmark of chromatin, but it remains unclear how they are generated. Recent genome-wide studies, in vitro and in vivo, showed constant nucleosome spacing even if the histone concentration was experimentally reduced. This counters the long-held assumption that nucleosome density determines spacing and calls for factors keeping spacing constant regardless of nucleosome density.

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While understanding translocation of DNA through a solid-state nanopore is vital for exploiting its potential for sensing and sequencing at the single-molecule level, surprisingly little is known about the dynamics of the propagation of DNA through the nanopore. Here we use linear double-stranded DNA molecules, assembled by the DNA origami technique, with markers at known positions in order to determine for the first time the local velocity of different segments along the length of the molecule. We observe large intramolecular velocity fluctuations, likely related to changes in the drag force as the DNA blob unfolds.

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Background And Purpose: Although poor-risk patients represent no minority in inoperable non-small cell lung cancer (NSCLC), there is little experience with concurrent radiochemotherapy (RCT) in this group. Here, the authors report on the feasibility and efficacy of RCT with vinorelbine plus carboplatin or cisplatin in NSCLC patients with comorbidities and poor general health or advanced age.

Patients And Methods: A total of 66 patients (ten women, 56 men, median age 68 years) with inoperable NSCLC and an increased risk of treatment side effects (WHO performance score of 2-3; cardiac, pulmonary or renal failure or extensive weight loss before treatment, or an age of 71-78 years) were treated with vinorelbine 12.

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Purpose: In the prospective study 02/96 on primary GI lymphoma, we have collected data on histology, clinical features, and treatment results. In particular, in stages I and II localized primary gastric lymphoma (PGL), our objectives were to reduce treatment intensity and to confirm our hypothesis from study 01/92, which maintained that an organ-preserving approach is not inferior to primary surgery.

Patients And Methods: Patients receiving radiotherapy and/or chemotherapy were stratified for histologic grade, stage, and whether surgery had been carried out or not (as decided by each participating center).

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Background And Purpose: Gastric carcinoma is characterized by a high rate of local recurrences and distant metastases and is often not resectable due to locally advanced stage. The aim of this study was to examine feasibility and effectiveness of neoadjuvant radiochemotherapy (RCT) for locally advanced, primarily nonresectable gastric carcinoma and to achieve curative resection.

Patients And Methods: 21 patients with locally advanced gastric cancer located in cardia (n = 17) and corpus (n = 4; seven cT3; 14 cT4; 18 cN+; all cM0) with a median age of 61 years were scheduled to receive neoadjuvant RCT.

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Two outbreaks of fowl cholera on a multiage free-range egg farm were investigated. The outbreaks occurred in 1994 and 2002. A total of 22 strains of Pasteurella multocida were available for study, 11 from the 1994 outbreak and 11 from the 2002 outbreak.

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Background: In elderly patients, patients with multiple morbidities, and patients with a reduced general condition, the standard treatment of inoperable non-small-cell lung cancer (NSCLC) consists of either chemotherapy or radiation therapy alone and is associated with an extremely poor prognosis. We therefore investigated the feasibility, toxicity, and efficacy of radiotherapy with concurrent chemotherapy using vinorelbine plus cisplatin or carboplatin in NSCLC patients at risk for treatment complications.

Patients And Methods: A total of 33 patients (six women, 27 men, median age 65 years) with locally advanced, functionally inoperable pulmonary carcinomas, recurrent lung cancer or postoperative macroscopic residual tumors (R2) with an increased risk of treatment complications (WHO performance status 2/3; cardiac, renal or pulmonary failure; marked pretherapeutic weight loss; age between 71-75 years) received 12.

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Objective: To observe the effect upon the foetus of experimental infection of pregnant cattle with Leptospira borgpetersenii serovar hardjo.

Design: A disease transmission study using pregnant cattle.

Procedure: Fourteen heifers serologically negative to L hardjo were artificially inseminated and later challenged with a north-Queensland isolate of L hardjo by conjunctival inoculation.

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Objective: To assess the effect of amoxycillin treatment on urinary excretion of leptospires from cattle infected with Leptospira borgpetersenii serovar hardjo.

Design: A chemotherapy trial with controls.

Procedure: Fourteen heifers serologically negative to L hardjo were inoculated with L hardjo via the conjunctival route and assessed for evidence of infection by serological, fluorescent antibody and microbiological tests.

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Laboratory examinations of equine morbillivirus included experimental reproductions of the disease caused by the virus by transmission of mixed lung and spleen taken from two field equine cases into two horses and by inoculating tissue culture virus into a further two horses. The most distinctive gross lesions of the diseases that developed in three of the horses was that of pulmonary edema characterized by gelatinous distension of subpleural lymphatics. Histologically, the lesions in the lungs were those of serofibrinous alveolar edema, alveolar macrophages, hemorrhage, thrombosis of capillaries, and syncytial cells.

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This paper reviews the laboratory diagnosis of Leptospira hardjo infection in cattle. Two genotypes of L hardjo, Hardjoprajitno and Hardjobovis, have been identified in cattle, but only Hardjobovis has been isolated in Australia. There are problems with diagnosis and control of bovine leptospirosis.

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Serious outbreaks of a paralytic disease in cattle occurring in the spring and summer of 1988 were investigated on three farms in south eastern Queensland, Australia. On one farm 237 (31 per cent) of 770 cattle died, on the second 109 (40 per cent) of 271 cattle died and on the third 30 (8 per cent) of 380 cows died. Botulism was suspected on the basis of the clinical signs, the lack of significant pathology, a failure to incriminate other agents and a positive feeding trial in one sheep.

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The clinical findings, pathology and mycology of a cluster of 5 ovine cases of rhinocerebral and nasal zygomycosis caused by Conidiobolus incongruus are described. All cases were in Border Leicester or Merino x Border Leicester ewes from a flock pastured in a low-lying paddock adjoining a small tidal river in subtropical Queensland (latitude 28 degrees S). These cases of zygomycosis are believed to be the first infections due to C incongruus recorded in animals other than humans.

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A goose flock farmed outdoors in south-eastern Queensland suffered an outbreak of peracute disease with high death rate (97%). Small button ulcers and large plaques overlying lymphocyte aggregates were present on the mucosa of the small intestine of affected birds. Small white foci of necrosis and focal haemorrhages were seen in the livers.

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The Rose Bengal Plate Agglutination test (RBT), the complement fixation text (CFT) and the tube agglutination test (TAT) were applied to serums from 345 feral and 80 domestic pigs sampled at slaughter. At least 2 of the 3 serological tests were applied to each serum. Tissues from all pigs were cultured for Brucella suis and the degree of culture effort was categorised from 1 to 4 in decreasing order.

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