Showing papers by "University of Basel published in 1983"
TL;DR: It is concluded that ethylene-induced chitinase functions as a defense enzyme against fungal and bacterial invaders.
Abstract: Ethylene induced an endochitinase in primary leaves of Phaseolus vulgaris L. The enzyme formed chitobiose and higher chitin oligosaccharides from insoluble, colloidal or regenerated chitin. Less than 5% of the total chitinolytic activity was detected in an exochitinase assay proposed by Abeles et al. (1970, Plant Physiol. 47, 129–134) for ethylene-induced chitinase. In ethylene-treated plants, chitinase activity started to increase after a lag of 6 h and was induced 30 fold within 24 h. Exogenously supplied ethylene at 1 nl ml−1 was sufficient for half-maximal induction, and enhancement of the endogenous ethylene formation also enhanced chitinase activity. Cycloheximide prevented the induction. Among various hydrolases tested, only chitinase and, to a lesser extent, β-1,3-glucanase were induced by ethylene. Induction of chitinase by ethylene occurred in many different plant species. Ethylene-induced chitinase was purified by affinity chromatography on a column of regenerated chitin. Its apparent molecular weight obtained by sodium dodecyl sulfate-gel electrophoresis was 30,000; the molecular weight determined from filtration through Sephadex G-75 was 22,000. The purified enzyme attacked chitin in isolated cell walls of Fusarium solani. It also acted as a lysozyme when incubated with Micrococcus lysodeikticus. It is concluded that ethylene-induced chitinase functions as a defense enzyme against fungal and bacterial invaders.
638 citations
270 citations
TL;DR: In this paper, the authors measured the deepinelastic electron scattering from carbon up to and including the Δ-region at 36°, 60°, 90° and 145°.
265 citations
TL;DR: The findings confirm that local neurons of different types contribute dendrites and axons to plaques and that these processes may proliferate within the confines of the plaques.
196 citations
TL;DR: Data obtained indicate that P2-5b is the protein responsible for the formation of the virus-induced vesicles.
182 citations
TL;DR: In this article, pig liver esterase-(PLE) catalyzed hydrolysis of dimethyl esters of symmetrical dicarboxylic acids, including meso-diacids, cis-1,2-cycloalkanedicar boxylic acid, and diacids with a prochiral center, was studied with 14 substrates.
Abstract: Pig liver esterase-(PLE) catalyzed hydrolysis of dimethyl esters of symmetrical dicarboxylic acids, including meso-diacids, cis-1,2-cycloalkanedicarboxylic acids, and diacids with a prochiral center, was studied with 14 substrates. The products of these stereoselective hydrolyses are chiral monoesters of dicarboxylic acids, with an enantiomeric excess (e.e.) from 10% to 100%. Some of these optically active monoesters are valuable synthons in natural products synthesis.
An additivity pattern of α- and β-substituents with the glutaric esters on the stereoselectivity of enzymatic hydrolysis was observed. Analysis of the experimental results leads to a model of enzyme stereoselectivity of diester hydrolysis in which the substitution pattern at α- and β-C-atoms is found to determine the absolute configuration of the resulting monoester.
174 citations
TL;DR: Autoradiograms or fluorograms can be quantified by eluting the silver grains from the developed film with 1 M NaOH and measuring the absorbance of the eluate in a conventional spectrometer.
162 citations
TL;DR: Dot hybridization analysis showed that small previtellogenic oocytes already contain a maximal amount of U1 (and U2) snRNAs, which then decreases to about 20% of that value in fully mature oocytes, even though the cell's volume has increased enormously.
153 citations
TL;DR: An integral membrane protein forming channels across Escherichia coli outer membranes, porin, has been crystallized using a polyethylene glycol or salt-generated two-phase system and monodispersity and homogeneity of protein-detergent complexes were found to be prerequisites for reproducible formation of crystals amenable to X-ray structural analysis.
149 citations
TL;DR: It is demonstrated that salicylaldehyde is derived from salicin, a phenylglucoside present in the leaves of the host plant, and is a more potent deterrent than saligenin orsalicin.
Abstract: . Phratora vitellinae L. and Chrysomela tremulae F. (Chrysomelinae, Coleoptera) feed on Salix or Populus spp. (Salicaceae). Their larvae, as well as the larvae of other chrysomelines feeding on Salicaceae, secrete salicylaldehyde. In this study, we demonstrate that salicylaldehyde is derived from salicin, a phenylglucoside present in the leaves of the host plant. The concentration of salicylaldehyde in the secretion is positively correlated with the amount of salicin in the food of the larvae. The transformation of salicin into salicylaldehyde occurs in the defence glands since the β-glucosidase activity is 4 times higher in their glands than in the gut. The larvae recover most of the glucose that results from the hydrolysis of salicin. For generalist predators, such as ants, salicylaldehyde is a more potent deterrent than saligenin or salicin.
147 citations
TL;DR: The structure of goose egg- white lysozyme has striking similarities to the lysozymes from hen egg-white and bacteriophage T4, however, some parts of goose ly sozyme resemble hen lyso enzyme while other parts correspond only to the phage enzyme, which strongly suggests that all three ly sozymes evolved from a common precursor.
Abstract: During evolution, the amino acid sequence of a protein is much more variable and changes more rapidly than its tertiary struc ture. Given sufficient time, the amino acid sequences of proteins derived from a common precursor may alter to the point that they are no longer demonstrably homologous. The ability to make meaningful comparisons between such distantly related proteins must therefore come primarily from structural homology, and only secondarily (if at all) from sequence homology1. On the other hand, structural homology in the absence of sequence homology might be attributed to convergent rather than divergent evolution. (A common fold might be dictated by functional or folding requirements.) We have previously argued, on the basis of structural and functional similarities, that the lysozymes of hen egg-white and bacteriophage T4 have a common evolutionary precursor, even though their amino acid sequences have no detectable similarity2,3. Here we report the structure of the lysozyme from Embden goose, a representative of a third class of lysozymes4–10 that has no sequence homology11,12 (or perhaps very weak homology13) with either the hen egg-white or the phage enzyme. The structure of goose egg-white lysozyme has striking similarities to the lysozymes from hen egg-white and bacteriophage T4. However, some parts of goose lysozyme resemble hen lysozyme while other parts correspond only to the phage enzyme. The nature of the structural correspondence strongly suggests that all three lysozymes evolved from a common precursor.
TL;DR: Two-dimensional crystalline porin sheets were obtained by reconstitution of monodisperse protein trimers and phospholipids by detergent dialysis by comparable method to that used for functional tests, and the packing arrangement appears very similar to the hexagonal habit of three-dimensional crystal forms.
TL;DR: The precursor of cytochrome b2 (a cytoplasmically‐synthesized mitochondrial protein) binds to isolated mitochondria or to isolated outer membrane vesicles and receptor‐like binding activity was present in isolated outer, but not inner membrane.
Abstract: The precursor of cytochrome b(2) (a cytoplasmically-synthesized mitochondrial protein) binds to isolated mitochondria or to isolated outer membrane vesicles. Binding does not require an energized inner membrane, is diminished by trypsin treatment of the membranes and is not observed with the partially processed (intermediate) form of the cytochrome b(2) precursor or with non-mitochondrial proteins. Upon energization of the mitochondria, the bound precursor is imported and cleaved to the mature form. Similar results were obtained with the precursor of citrate synthase. This receptor-like binding activity was present in isolated outer, but not inner membrane. It was solubilized from outer membrane with non-ionic detergent and reconstituted into liposomes.
TL;DR: The structure--function relationship of laminin and its role in embryogenesis and various diseases is under investigation.
TL;DR: The DNA sequence of a new IS element, the IS26, is 820 bp long and carries 14 bp perfect terminal inverted repeats, and upon integration, IS26 generates an 8 bp duplication of its target sequence.
Abstract: The DNA sequence of a new IS element, the IS26, is 820 bp long and carries 14 bp perfect terminal inverted repeats. Upon integration, IS26 generates an 8 bp duplication of its target sequence. A large open reading frame within IS26 could code for a protein of 234 amino acids. On its reverse strand, IS26 also carries one large open reading frame, 591 bp long, which contains no stop codon within IS26.
TL;DR: Protease treatment and immunochemical techniques showed that virtually all of the isolated outer membrane vesicles are sealed and display the same surface orientation as in the intact mitochondrion.
Abstract: The yeast mitochondrial outer membrane was isolated and 10 of its major polypeptides were identified (mol. wts. 109, 70, 57, 45, 45, 42, 33, 29, 25 and 14 kd). The membrane has no major polypeptide in common with either mitochondrial inner membrane or rough microsomes. Protease treatment and immunochemical techniques showed that virtually all of the isolated outer membrane vesicles are sealed and display the same surface orientation as in the intact mitochondrion.
TL;DR: Human CG‐α‐appears to be a reliable quantitative and qualitative marker for malignancy in functioning pancreatic endocrine tumors.
Abstract: Human chorionic gonadotropin (hCG) or its alpha- and beta-subunits have been proposed as specific quantitative markers for malignant pancreatic endocrine tumors Since proof of malignancy of pancreatic endocrine tumors is difficult early in the course of the illness, we tested retrospectively a series of 157 pancreatic endocrine tumors of 155 patients for alpha- or beta-subunits of hCG by immunocytochemistry Human CG-alpha-immunoreactive cells were present in 42 of 56 (75%) functioning malignant pancreatic endocrine tumors but in only one, possibly benign, glucagonoma of 67 functioning benign tumors, in only one of 17 nonfunctioning malignant and in none of 17 nonfunctioning benign tumors No beta-hCG-immunoreactivity was localized in the tumors Human CG-alpha appears to be a reliable quantitative and qualitative marker for malignancy in functioning pancreatic endocrine tumors
TL;DR: The impact of smoking on medical care expenditure is analyzed, challenging the widespread belief that smoking imposes a large cost burden on health services systems and suggesting that reducing smoking is unlikely to decrease it.
TL;DR: A heterogenous distribution of opiate binding sites was found with the neocortical and cerebellar cortices being very rich, brainstem generally poor and white matter very poor in opiate receptor sites.
TL;DR: In this paper, the authors measured valence-band photoelectron spectra for the transition-metal glasses of Zr and showed that the results were consistent with the occurrence of superconductivity and with trends in the transition temperatures of glassy alloys with Zr.
Abstract: Measured valence-band photoelectron spectra for the transition-metal glasses ${A}_{x}{\mathrm{Zr}}_{100\ensuremath{-}x}$ ($A=\mathrm{F}\mathrm{e},\phantom{\rule{0ex}{0ex}}\mathrm{C}\mathrm{o},\phantom{\rule{0ex}{0ex}}\mathrm{N}\mathrm{i},\phantom{\rule{0ex}{0ex}}\mathrm{C}\mathrm{u},\phantom{\rule{0ex}{0ex}}\mathrm{R}\mathrm{h},\phantom{\rule{0ex}{0ex}}\mathrm{a}\mathrm{n}\mathrm{d}\phantom{\rule{0ex}{0ex}}\mathrm{P}\mathrm{d}$, with $x$ approximately 25) are shown to be in good agreement with self-consistent energy-band state densities for ordered compounds in the Au${\mathrm{Cu}}_{3}$ (fcc-like) crystal structure. The calculations and measurements both yield high Fermi-level state densities, account for core-level line shapes, and are consistent with the occurrence of superconductivity and with trends in the transition temperatures of glassy alloys of Zr with $3d$ transition metals.
TL;DR: It is suggested the possibility that fibronectin and laminin form a continuous matrix surrounding the cells which links the outer ECM (hyaline layer) to the innerECM (basement membrane) and could coordinate the various activities of the embryo during early morphogenesis.
TL;DR: For a treatment in terms of appropriate thermodynamic parameters a simple model is examined in greater detail and some useful points regarding the evaluation of raw data without recourse to any specific binding mechanism are discussed first.
TL;DR: The pattern of connection is compatible with the hypothesis that a roll or downward pitch deviation induces compensating movements of the wings to correct the deviation, and the roles of the two pathways are discussed.
Abstract: 1. 1. This paper deals with the physiology, anatomy and function of the following classes of neurones in the locust Schistocerca : (a) neurones carrying ocellar information to the pterothorax (Descending Ocellar Neurones, DONs), (b) mesothoracic Flight Motor Neurones (FMNs), (c) a heterogenous class of inter- and intraganglionic thoracic interneurones which receive input from the DONs, here called Thoracic Ocellar Interneurones (TONs) without prejudice to their other possible inputs and functions.
2. 2. The thoracic arborizations of five different DONs are characterized. All project unilaterally to the pterothorax, four out of five to the ipsilateral mesothoracic or meso- and metathoracic ganglia. All are phasic OFF units, responding to stimulation either of one lateral ocellus or of the medial ocellus or of both, but none responded to the cephalic wind-hairs. Four of the five DONs showed no response decrement at stimulus frequencies up to 80 Hz. One showed habituation, recovery during a rest interval, and dishabituation in response to mechanical stimulation of a leg. There are more than six DONs, probably more than ten, in each connective.
3. 3. All types of recorded mesothoracic FMNs receive monosynaptic EPSPs from the DONs and/or delayed IPSPs (presumably via TONs) in at least some animals. The pattern of connection is compatible with the hypothesis that a roll or downward pitch deviation induces compensating movements of the wings to correct the deviation. Many of these DON/FMN connections were, however, only occasionally recorded. None of the ocellar EPSPs recorded in the FMNs elicited spikes.
4. 4. Most TONs receive monosynaptic EPSPs from one or more DONs, sometimes causing them to spike. Two receive delayed IPSPs, presumably via other TONs. At least one third of the recorded TONs spike in phase with either elevator or depressor FMNs during stimulated flight. Intraganglionic TONs in the mesothorax are all unilateral. Their anatomy suggests that they distribute input from DONs to various combinations of ipsilateral FMNs. Interganglionic TONs can be either unilateral or bilateral in the mesothoracic ganglion, and project unilaterally to the metathoracic (or rarely the prothoracic) ganglion, where at least one makes inhibitory synapses with a FMN.
5. 5. Phasic ocellar information reaches the FMNs by two routes. One produces fast subthreshold PSPs in the FMNs directly. The other produces spikes and PSPs in thoracic interneurones, at least some of which are phasically active during flight and are presynaptic to FMNs. The roles of the two pathways are discussed.
TL;DR: There were significant increases with age in right atrial, pulmonary artery and wedge pressures, pulmonary to wedge pressure gradient and flow resistance, but cardiac output was not influenced by age.
Abstract: 1. To determine the effects of age on the pulmonary circulation at rest and on exercise we analysed the results of right heart catheterization studies performed in 125 asymptomatic subjects aged 14-68 years, who were healthy or had indispositions which did not impair cardiac or pulmonary function. 2. Age accounted for less than 10% of total variation in resting values of right atrial, pulmonary artery and wedge pressures, and of cardiac output. 3. The pulmonary artery-wedge pressure gradient and flow resistance at rest significantly increased with age. 4. On exercise there were significant increases with age in right atrial, pulmonary artery and wedge pressures, pulmonary to wedge pressure gradient and flow resistance, but cardiac output was not influenced by age. 5. Pulmonary circulation variables at rest are mainly influenced by sex and size, but during exercise significant effects of age are apparent.
TL;DR: The EcoP1 and EcoP15 DNA restriction-modification systems are coded by the related P1 prophage and p15B plasmid and the results of transposon mutagenesis, restriction cleavage analysis and in vitro transcription mapping allow the following conclusions to be drawn concerning the structural genes.
TL;DR: Analysis indicates that low temperature (-35 degrees C) treatment increased the specificity and density of pAg labeled anti-tubulin antibodies to Leishmania tropica subpellicular microtubules as compared to samples prepared at 0 degrees C or 20 degrees C.
Abstract: Qualitative and quantitative tests were performed to determine whether the temperature at which dehydration and embedding occur affects the antigenic specificity of tubulin and the protein A-gold (pAg) immunolabeling technique. The analysis indicates that low temperature (-35 degrees C) treatment increased the specificity and density of pAg labeled anti-tubulin antibodies to Leishmania tropica subpellicular microtubules as compared to samples prepared at 0 degrees C or 20 degrees C.
Journal Article•
TL;DR: Corynebacterium parvum administered i.p. has inhibited the growth of human ovarian carcinoma and may prove useful for modulating the activity of human effectors for antibody-dependent cell-mediated cytotoxicity.
Abstract: Corynebacterium parvum has been administered i.p. to 14 patients with advanced ovarian cancer. Two patients had re sponded completely to cytoreductive surgery and combination chemotherapy prior to immunotherapy, and one patient with residual disease had received only a single course of C. parvum due to i.p. catheter malfunction. Among the 11 patients with residual disease A©valuable for response, from three to eight i.p. treatments with C. parvum produced surgically confirmed tu mor regression in five patients (45%) with three partial re sponses and two complete responses of 5 and 12 months duration. All responders had (a) multiple tumor nodules <0.5 cm at the initiation of immunotherapy, and (b) severe abdominal pain and fever after C. parvum injection. Overall, 58 courses of immunotherapy were associated with abdominal pain (91%), fever (67%), nausea (52%), vomiting (31%), and hypotension that responded promptly to i.v. infusion of fluids (10%). Use of i.p. cathethers was associated with two episodes each of infection and intraabdominal bleeding. Administration of C. parvum i.p. has augmented the ability of human peritoneal cells to lyse human ovarian carcinoma cell lines in the presence of specific rabbit heteroantiserum. C. parvum administered i.p. has inhibited the growth of human ovarian carcinoma and may prove useful for modulating the activity of human effectors for antibody-dependent cell-mediated cytotoxicity.
TL;DR: Sixteen streams in the Black Forest, Vosges, Swiss Jura and Napf regions with different geology and climate, reflected by variations in water chemistry and riparian vegetation, were investigated for aquatic fungal communities, indicating that fungal species richness is negatively correlated with pH and associated factors whereas the riparians vegetation shows no influence.
Abstract: Sixteen streams in the Black Forest, Vosges, Swiss Jura and Napf regions with different geology and climate, reflected by variations in water chemistry and riparian vegetation, were investigated for aquatic fungal communities. Linear correlation and regression analysis as well as χ2-tests indicate that fungal species richness is negatively correlated with pH and associated factors (conductivity, alkalinity, calcium and magnesium content) whereas the riparian vegetation shows no influence. In contrast, average annual spore concentration in the streams is little influenced by the water chemistry, but is significantly connected with the riparian vegetation. A similarity index (Sorensen index) indicates that similarity between the different fungal communities is highest within the same regions and is dissimilar when communities of different regions are compared.