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1.
Infection ; 24(5): 347-53, 1996.
Article in English | MEDLINE | ID: mdl-8923044

ABSTRACT

The presence of Borrelia burgdorferi DNA was established by PCR from urine samples of 97 patients clinically diagnosed as presenting with symptoms of chronic Lyme disease. All patients had shown erythema chronica migrans following a deer tick bite. Most of the patients had been antibiotic-treated for extended periods of time. We used three sets of primer pairs with DNA sequences for the gene coding of outer surface protein A (OspA) and of a genomic sequence of B. burgdorferi to study samples of physician-referred patients from the mideastern USA. Controls from 62 healthy volunteers of the same geographic areas were routinely carried through the procedures in parallel with patients' samples. Of the 97 patients, 72 (74.2%) were found with positive PCR and the rest with negative PCR. The 62 healthy volunteers were PCR negative. It is proposed that a sizeable group of patients diagnosed on clinical grounds as having chronic Lyme disease may still excrete Borrelia DNA, and may do so in spite of intensive antibiotic treatment.


Subject(s)
Borrelia burgdorferi Group/genetics , Borrelia burgdorferi Group/isolation & purification , DNA, Bacterial/isolation & purification , Lipoproteins , Lyme Disease/genetics , Anti-Bacterial Agents/therapeutic use , Antigens, Surface/genetics , Bacterial Outer Membrane Proteins/genetics , Bacterial Vaccines , Chronic Disease , Electrophoresis, Agar Gel , Genome, Bacterial , Humans , Lyme Disease/drug therapy , Lyme Disease/epidemiology , Lyme Disease/urine , Molecular Epidemiology , Molecular Sequence Data , Polymerase Chain Reaction/methods , United States/epidemiology
2.
In Vivo ; 8(1): 3-15, 1994.
Article in English | MEDLINE | ID: mdl-8054508

ABSTRACT

Tumorigenesis in eukaryotic organisms is based on the deregulation of normal cell growth and development. This deregulation may be elicited by external as well as endogenous factors. We distinguish between benign and malignant growths depending on the inducing tumorigenic agents and on the genetic make-up of the affected organism. This review discusses similarities of neoplasmatic (epigenetic) and neoplastic transformations in plants and animals as well as inherent differences in the growth parameters between the two kingdoms. Examples given for neoplasmatic tissues are the hyperplasias and insect galls (zoocecidia) in plants and hypoplasia, aplasia and agenesis in animals (and man). Neoplastic transformation in plants is the result of either the incorporation of foreign nuclear material into the plant genome or an imbalance of inherited chromosomes (in hybrids). Examples for neoplasias are the crown gall disease and Kostoff's genetic tumors in plants, and the carcinomas and leukemias in animals. The more than 80 year old, but neglected, concept of a correlation between tumorigenesis in animals and plants has been revived through advances in molecular and cell biology and molecular genetics which will stimulate a new form of biological reasoning and thought, fueled by new insights into cellular regulatory processes.


Subject(s)
Cell Division , Cell Transformation, Neoplastic , Growth/physiology , Neoplasms/pathology , Plant Development , Plant Tumors , Animals , Humans , Plant Cells
3.
J Bacteriol ; 173(1): 141-9, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1987113

ABSTRACT

Treatment of growing Escherichia coli B with lanthanide ions [lanthanum(III), terbium(III), and europium(III)] and subsequent aldehyde-OsO4 fixation caused areas of high contrast to appear within the periplasm (the space between inner and outer membrane of the cell envelope). X-ray microanalysis of ultrathin sections of Epon-embedded or acrylic resin-embedded cells revealed the presence of the lanthanide and of phosphorus in the areas, whose contrast greatly exceeded that of other stained structures. Comparatively small amounts of the lanthanide were also present in the outer membrane and in the cytoplasm. The distribution of the periplasmic areas of high contrast was found to be random and not clustered at areas of current or future septum formation. Irregular cell shapes were observed after lanthanide treatment before onset of fixation. In contrast to glutaraldehyde-OsO4 fixation, glutaraldehyde used as the sole fixer caused a scattered distribution of the lanthanide. Cryofixation (slam-freezing) and freeze substitution revealed a lanthanum stain at both the periplasm and the outer part of the outer membrane. Deenergization of the cell membrane by either phage T4 or carbonyl cyanide m-chlorophenylhydrazone abolished the metal accumulation. Furthermore, addition of excess calcium, administered together with the lanthanide solution, diminished the quantity and size of areas of high contrast. Cells grown in media of high NaCl concentration revealed strongly stained areas of periplasmic precipitates, whereas cells grown under low-salt conditions showed very few high-contrast patches in the periplasm. Terbium treatment (during fixation) enhanced the visibility of the sites of inner-outer membrane contact (the membrane adhesion sites) in plasmolized cells, possibly as the result of an accumulation of the metal at the adhesion domains. The data suggest a rapid interaction of the lanthanides with components of the cell envelope, the periplasm, and the energized inner membrane.


Subject(s)
Escherichia coli/ultrastructure , Europium/metabolism , Lanthanum/metabolism , Terbium/metabolism , Bacteriological Techniques , Electron Probe Microanalysis , Escherichia coli/growth & development , Microscopy, Electron , T-Phages/ultrastructure
4.
J Bacteriol ; 172(1): 125-35, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2403537

ABSTRACT

We report the localization of penicillin-binding protein 1b (PBP 1b) in Escherichia coli KN126 and in an overproducing construct containing plasmid pHK231. We used PBP 1b-specific antiserum for the immunoelectron microscopy of ultrathin sections of whole cells and for immunoelectrophoresis of cytoplasm and isolated membrane fractions. We studied ultrathin sections of both glutaraldehyde-fixed cells that had been embedded after progressively lowering the temperature and cryofixed cells that had been freeze-substituted in Lowicryl K4M and HM20. Most of the PBP 1b-specific label was observed in the inner membrane (IM) and the adjacent cytoplasm, much less was observed in the outer membrane (OM); appreciable amounts were also seen in the bulk cytoplasm. Distribution and intensity of label were both temperature dependent: temperature shift-up to 37 degrees C, causing PBP 1b overproduction in the construct, showed a statistically highly significant increase in label of the IM, including a cytoplasmic zone (of at least 30 nm in depth) adjacent to the IM, a zone we termed the membrane-associated area. Concomitant with the temperature shift-up, a decrease in label density was observed in the bulk cytoplasm. Increased label was also found in IM-OM contact areas (zones of membrane adhesion). The periplasm did not show significant label. Western blotting (immunoblotting) revealed PBP 1b in most of the isolated membrane fractions; however, the highest label density was found in membrane fractions of intermediate density, supporting the suggestion of an increased concentration of PBP 1b in the membrane adhesion zones. In summarizing, we propose that PBP 1b is present in the membrane-associated area of the cytoplasm, from where proteins (such as PBP 1b or thioredoxin) gain access to their specific insertion sites in the envelope. The use of several methods of immunoelectron microscopy provided the first unequivocal evidence for localization of PBP 1b at membrane adhesion sites. Since such sites are specifically labeled with anti-PBP 1b serum, we hypothesize that they contain parts of the machinery for assembly and growth of the murein layer.


Subject(s)
Acyltransferases/analysis , Bacterial Proteins , Carrier Proteins , Escherichia coli/analysis , Hexosyltransferases/analysis , Multienzyme Complexes/analysis , Muramoylpentapeptide Carboxypeptidase , Peptidyl Transferases/analysis , Blotting, Western , Cell Membrane/analysis , Cytoplasm/analysis , Electrophoresis, Polyacrylamide Gel , Immunoelectrophoresis , Microscopy, Electron , Penicillin G/metabolism , Penicillin-Binding Proteins
5.
J Bacteriol ; 169(6): 2659-66, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3294802

ABSTRACT

The intracellular localization of thioredoxin in Escherichia coli was determined by immunoelectron microscopy and correlated to previous biochemical data which had suggested that thioredoxin resides at inner-outer membrane adhesion sites. Since a considerable amount of thioredoxin was lost during preparation of cells for electron microscopy, we immobilized the protein with the heterobifunctional photoactivatable cross-linker p-azidophenacylbromide before the cells were fixed with aldehyde and embedded in Lowicryl K4M. Thin sections were labeled with affinity-purified antithioredoxin antiserum and protein A-gold complexes. Densities of immunolabel in a designated membrane-associated area and in the rest of the cytoplasm were compared and the data were statistically evaluated. Wild-type strain W3110 and strain SK3981, an overproducer of thioredoxin, exhibited increased labeling at the inner membrane and its adjacent cytoplasmic area. In contrast, the more centrally located cytoplasm of both strains showed much lower label density. This label distribution did not change with cell growth or in the stationary phase. Immunolabel was often found at bridges between the inner and outer membranes; this result is consistent with a model which places at least a portion of the thioredoxin at membrane adhesion sites, corresponding to an osmotically sensitive cytoplasmic compartment bounded by a hybrid inner-outer membrane (C.A. Lunn and V. Pigiet, J. Biol. Chem. 257:11424-11430, 1982; C.A. Lunn and V. Pigiet, J. Biol. Chem. 261:832-838, 1986). Specific label was absent in the periplasmic space.


Subject(s)
Bacterial Proteins/metabolism , Escherichia coli/metabolism , Thioredoxins/metabolism , Azides , Binding Sites , Cell Compartmentation , Cell Membrane/metabolism , Cross-Linking Reagents , Escherichia coli/ultrastructure , Immunosorbent Techniques , Microscopy, Electron , Photochemistry
6.
J Virol ; 57(1): 258-66, 1986 Jan.
Article in English | MEDLINE | ID: mdl-2867229

ABSTRACT

Phage fd-infected host bacteria revealed three characteristic changes in their envelope. (i) The preferred cleavage plane during freeze-fracturing shifted from the inner to the outer membrane (OM). (ii) The total lipids of the OM of the infected cells increased by 25% without major alterations in the relative concentration of phospholipids. We propose that such an increase would to some extent contribute to the change in the freeze-fracture behavior of the OM; however, additional factors will have to play a role in the apparent fracture resistance of the inner membrane. (iii) Ultrathin sectioning and immunolabeling methods revealed that extrusion of fd phages takes place at membrane adhesion sites of the infected cells.


Subject(s)
Coliphages/growth & development , Escherichia coli/ultrastructure , Virus Replication , Cell Membrane/analysis , Cell Membrane/ultrastructure , Coliphages/physiology , Escherichia coli/analysis , Fimbriae, Bacterial/ultrastructure , Freeze Etching , Freeze Fracturing , Membrane Lipids/analysis , Microscopy, Electron , Phospholipids/analysis
7.
J Bacteriol ; 162(1): 50-4, 1985 Apr.
Article in English | MEDLINE | ID: mdl-3920208

ABSTRACT

The phospholipid composition and the phospholipase C activity of envelope fractions of Escherichia coli B were determined with special consideration of fractions containing sites at which an attachment of inner and outer membranes had been observed in the electron microscope (Int.M). Phosphoglycerides labeled with [14C]palmitic acid and [3H]serine were extracted from membrane fractions and identified by two-dimensional thin-layer chromatography. The amount of phosphatidylethanolamine was highest in the outer membrane, whereas the amounts of phosphatidylglycerol and cardiolipin were highest in the inner membrane. The Int.M fractions were observed to have concentrations of phospholipids intermediate to those of the inner and outer membranes. This result supports the assumption that a concentration gradient of inner membrane-outer membrane lipids might exist at the membrane contact sites. The highest phospholipase C activity was detected in the inner membrane and Int.M fractions. The presence of phospholipase C and other lipolytic enzymes in the Int.M fractions suggests a possible involvement of adhesion sites in lipid metabolism, adding a further set of activities to the function of these domains.


Subject(s)
Escherichia coli/analysis , Glycerophosphates/analysis , Phospholipases/analysis , Type C Phospholipases/analysis , Cell Membrane/analysis , Lysophospholipase/analysis , Palmitic Acid , Palmitic Acids/metabolism , Phosphatidylcholines/metabolism , Serine/metabolism
8.
Plant Physiol ; 73(1): 179-81, 1983 Sep.
Article in English | MEDLINE | ID: mdl-16663171

ABSTRACT

Phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine and cardiolipin are the major phospholipids in young leaves of black oak (Quercus robor L.). Except for phosphatidylcholine, young, developing cynipid-galls on black oak leaves, i.e. the insect-transformed tissues, contain less phospholipid than normal leaf tissues. Lipid acyl hydrolase activity determined by the cleavage of free fatty acids from a labeled phospholipid substrate is higher in the tissue extracts from galls than from leaves. The increase in enzyme activity and the altered phospholipid composition are discussed in relation to expected membrane modifications and transport phenomena in insect-transformed tissues.

9.
Biochim Biophys Acta ; 692(3): 498-500, 1982 Nov 22.
Article in English | MEDLINE | ID: mdl-7171606

ABSTRACT

Phospholipase A activity was detected in commercial DNAases I and II and in RNAase preparations. The amount of phospholipase correlates inversely with the degree of nuclease purification. The assessment of the level of phospholipase in commercial nucleases is important in cases where enzymatic properties other than those of DNAases and RNAases are to be investigated and when these preparations are to be used in the isolation of biological membranes.


Subject(s)
Deoxyribonucleases/isolation & purification , Phospholipases A/isolation & purification , Phospholipases/isolation & purification , Ribonucleases/isolation & purification , Cell Fractionation , Indicators and Reagents , Membranes/ultrastructure , Phospholipases A/metabolism
10.
J Bacteriol ; 149(2): 758-67, 1982 Feb.
Article in English | MEDLINE | ID: mdl-7056701

ABSTRACT

At areas of adhesion between outer membrane (OM) and inner membrane (IM) in gram-negative bacteria, newly synthesized membrane constituents are inserted, and bacteriophage infection occurs. We describe here the isolation of these sites from cell membrane fractions of Salmonella anatum. Sucrose density gradients yielded membrane vesicles of the OM and IM; their mutual cross-contamination was low, as measured by 2-keto-3-deoxyoctonate and beta-NADH-oxidase activities. To mark the areas of lipopolysaccharide synthesis in the envelope (the adhesion sites), we infected S. anatum with phage epsilon 15, which causes a rapid change (conversion) in the cell's O-antigenic composition from serogroup E1 to E2; lipopolysaccharide of type E2 also serves as receptor for phage epsilon 34. We found that the fractions of intermediate density (Int. M) from briefly converted cells bound both phage epsilon 34 and E2-specific antibody. In the electron microscope, epsilon 34 was seen to have absorbed with a high degree of significance to the Int. M fraction of briefly converted cells, but not to the Int. M fraction of unconverted cells. Furthermore, the Int. M fractions of briefly converted cells coagglutinated anti-E2-coated Staphylococcus aureus, whereas the OM and IM fractions showed comparatively little agglutination. In addition, Int. M material exhibited elevated phospholipase A1 and A2 activities comparable to those of the OM fraction; the IM was essentially phospholipase free. Our data indicate that this membrane fractionation allows one to isolate from Int. M regions a variety of activities associated with adhesion sites.


Subject(s)
Cell Fractionation , Cell Membrane/ultrastructure , Salmonella/ultrastructure , Agglutination , Cell Membrane/physiology , Lysophospholipase/metabolism , Phospholipases A/metabolism , Phospholipases A1 , Receptors, Virus/metabolism , Salmonella Phages/metabolism
11.
Proc Natl Acad Sci U S A ; 78(9): 5618-22, 1981 Sep.
Article in English | MEDLINE | ID: mdl-7029540

ABSTRACT

After collision with their host cells, virus particles may remain mobile on cell surfaces until they become attached at firm binding sites. We propose that a virion will arrive within a typical median time at such a site, generating a membrane signal such as an increased membrane fluorescence in cells labeled with the voltage-sensitive dyes 8-anilino-1-naphthalene-sulfonate (Mg-salt) (ANS), N-phenylnaphthylamine (NPA), or 3,3'-dipentyl-2,2'-oxacarbocyanine (di-O-C5[3]). We found that the time span between virus adsorption and fluorescence response varies widely among phages and also depends on bacterial strain, metabolic state, and type of dye. di-O-C5[3]-labeled cells react within 1 sec to uncouplers such as carbonyl cyanide m-chlorophenylhydrazone (CCCP). Cells labeled with ANS and NPA react to CCCP in 4-6 sec. Bacteriophages T4, T5, chi, and BF23, added to ANS-labeled cells, change the fluorescence in 9-15 sec. T-even ghosts cause a response at identical times. Baseplate-defective phage mutant T412- and isolated adsorption organelles of smaller viruses fail to cause an effect. di-O-C5[3]-labeled cells respond to T4 at a multiplicity of infection greater than or equal to 40 within 1 sec. A longer time (8 sec) is required at lower multiplicities. The receptor-degrading phages epsilon 15, epsilon 34, c 341, and K29 need the longest time (1 min for ANS) to cause a fluorescence increase. We suggest that the delayed fluorescence response is concomitant with the surface "walk" of the virion, which is terminated at an injection site. T4 tail sheath contraction coincides with the onset of the membrane fluorescence response.


Subject(s)
Bacteriophages/physiology , Cell Membrane/physiology , Receptors, Virus/physiology , Escherichia coli/physiology , Fluorescent Dyes , Membrane Lipids/physiology , Membrane Potentials , Salmonella/physiology
13.
Plant Physiol ; 51(5): 898-901, 1973 May.
Article in English | MEDLINE | ID: mdl-16658436

ABSTRACT

Enzymatically isolated mesophyll protoplasts of the two normal, nontumor-forming parent species Nicotiana glauca and N. langsdorffii and two of their tumor-prone interspecific hybrids were maintained in a 0.5 m mannitol solution supplemented with various concentrations of auxin (indoleacetic acid) and the growth inhibitor abscisic acid. The bursting response of protoplasts in medium containing indoleacetic acid in physiological concentrations showed that protoplasts from the tumorous hybrids tolerate auxin in up to 30 times higher concentrations than protoplasts from parent plants. The "survival" of all protoplast preparations in comparable abscisic acid containing media was significantly greater than that in the indoleacetic acid supplemented solutions. Protoplasts in vitro respond with bursting only after the external indoleacetic acid concentrations reach levels comparable to those of endogenous auxins present in these cells. The data are discussed in conjunction with previous observations on uptake and maintenance of indoleacetic acid levels in tumorous Nicotiana tissues.

14.
Plant Physiol ; 44(2): 267-71, 1969 Feb.
Article in English | MEDLINE | ID: mdl-5774173

ABSTRACT

Acidic indole auxins have been extracted from N. glauca, N. langsdorffii and their 2 tumor-prone 4n- and 2n-hybrids. After purification of the extracts and thin-layer chromatography, acidic indoles were subjected to esterification and gas chromatography. The esters of 4 indole acids were detected and determined: indole-3-acetic acid, indole-3-carboxylic acid, indole-3-propionic acid and indole-3-butyric acid. The indolic nature of fractionated samples was confirmed by spectrophotofluorometry and the physiological significance of the indole esters proven in a biotest. A substantial increase in extractable indole-3-butyric acid in the tumor-prone hybrids suggests an additional pathway of auxin synthesis in these tissues.


Subject(s)
Indoles/analysis , Nicotiana/analysis , Plant Growth Regulators/analysis , Plants, Toxic , Biological Assay , Butyrates/analysis , Chromatography, Gas , Fluorometry , Hybridization, Genetic , Indoleacetic Acids/analysis , Methods , Plant Growth Regulators/isolation & purification , Plant Tumors , Spectrophotometry
15.
Planta ; 79(4): 292-8, 1968 Dec.
Article in English | MEDLINE | ID: mdl-24522901

ABSTRACT

Auxin and auxin-inhibitors from acidic ether extracts of normal stem tissue of Nicotiana longiflora, N. debneyi-tabacum, their tumor producing F 1 hybrid and non-tumor and tumor-prone segregants were separated by thin-layer chromatography and measured by an Avena curvature test. A significantly higher amount of auxin, very likely IAA, was found in the F 1 hybrid and the tumor-prone segregants as compared to the non-tumor tissues. Inhibitory substances appeared at different Rf's but generally in low amounts. One inhibitor seems to be identical with the "inhibitor ß". In general, the results indicate that higher levels of auxin are associated with tumor-prone tissues in the F 1 hybrid and the segregants of a later generation carrying an alien longiflora chromosome on a debneyi-tabacum background. The role of this growth-regulating substance as related to tumor formation in Nicotiana is discussed.

16.
Planta ; 72(4): 329-37, 1967 Dec.
Article in English | MEDLINE | ID: mdl-24554326

ABSTRACT

Auxin and auxin-inhibitors from acidic ether extracts of normal Nicotiana stem tissues of N. glauca and N. langsdorffii and their tumor-producing 4n, 3n, and 2n-hybrids were separated by thin-layer chromatography. The growth substances were eluted and subjected to an Avena curvature test. A considerably higher amount of IAA was found in the tumor-forming 2n-hybrid (GL) than in the other plant material. The 4n-hybrid (GGLL) showed a small but significant increase in extractable IAA in comparison to its parents, whereas the 3n-hybrid (LLG) showed no difference from the langsdorffii parent. Inhibitory substances appeared at different Rf's but generally in low quantities. The inhibitor at Rf 0.5-0.6 (chromatography in n-butanol water-ammonia, 10: 10: 1, upper phase) seems to be identical with the "inhibitor ß" of BENNETT-CLARK and KEFFORD (1953). The results indicate that the potential for massive tumor production in the 2n- and 4n-hybrids of N. glauca x N. langsdorffii plants is coupled with increased IAA and inhibitor levels, whereas the 3n-hybrid, which forms tumors of much smaller size and in a later stage of development, does not differ considerably in its extractable IAA content from its N. langsdorffii parent.

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