Ca2+-dependence and metabolic status of an obligate thermophile,Thermoactinomyces vulgaris, under shake culture conditions

V. P. Singh; U. Sinha

doi:10.1007/bf01964084

Effect of linoleic acid on reproduction and yeast–mycelium dimorphism in the Dutch elm disease pathogens

Botany ◽

10.1139/cjb-2015-0156 ◽

2016 ◽

Vol 94 (1) ◽

pp. 31-39 ◽

Cited By ~ 8

Author(s):

Erika Sayuri Naruzawa ◽

Fabienne Malagnac ◽

Louis Bernier

Keyword(s):

Linoleic Acid ◽

North America ◽

Vascular Disease ◽

Minimal Medium ◽

Nuclear Genome ◽

Culture Conditions ◽

Dutch Elm Disease ◽

Shake Culture ◽

Reproductive Structures ◽

Sexual Crosses

Elm populations from North America and Europe were devastated by Dutch elm disease (DED), which is a vascular disease caused by fungi from the genus Ophiostoma (Ascomycota). These pathogens feature a yeast–mycelium dimorphism that may be related to virulence by facilitating colonization of the host xylem. Cyclooxygenases (COX) have been proposed to modulate yeast–mycelium dimorphism of DED fungi, and homologs of cox genes have been found in the nuclear genome of O. novo-ulmi subsp. novo-ulmi. Linoleic acid, a substrate for COX, was reported to stimulate the formation of asexual and sexual reproduction structures in DED strains grown on complex media. We hypothesized that linoleic acid also induced mycelium production in liquid shake culture conditions. Linoleic acid was found to enhance the production of reproductive structures in sexual crosses conducted on a complex medium (elm sapwood agar), but was not sufficient for these structures to form on a minimal medium. In liquid shake cultures grown in a minimal medium, the addition of linoleic acid stimulated mycelial formation. Our results suggest that linoleic acid plays a role in reproduction and dimorphism in the DED pathogens.

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Ultrastructure of the effect of T-514 obtained from Karwinskia humboldtiana on assembly and integrity of yeast's peroxisomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084983 ◽

1991 ◽

Vol 49 ◽

pp. 136-137

Author(s):

J. Sepulveda-Saavedra ◽

I. Vander-Klei ◽

M. Venhuis ◽

Y. Piñeyro-Lopez

Keyword(s):

Culture Conditions ◽

Toxic Effects ◽

Candida Boidinii ◽

Central Mexico ◽

Poisonous Plant ◽

Biological Behaviour ◽

Enzyme Content ◽

Fat Deposits ◽

Yeast Model

Karwinskia humboldtiana is a poisonous plant that grows in semi desertic areas in north and central México. It produces several substances with different toxic effects. One of them designated T-514 damages severely the lung, kidney and liver, producing in the hepatoeyte large intracellular fat deposits and necrosis. Preliminary observations demonstrated that three is a decrease in the amount of peroxisomes in the hepatocytes of experimentally intoxicated rats and monkeys. To study the effect exerted by the T-514 on peroxisomes, a yeast model was selected, thus, three species: Saccha romices cerevisiae, Ilansenula polymorpha and Candida boidinii were used, because there is information concerning their peroxisome's morphology, enzyme content, biological behaviour under different culture conditions and biogenesis.

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Scanning Microscopy of Human Intestinal Explants in Organ Culture

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095248 ◽

1972 ◽

Vol 30 ◽

pp. 396-397

Author(s):

Bruce Wetzel ◽

Robert Buscho ◽

Raphael Dolin

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Culture Conditions ◽

Human Fetuses ◽

Enteric Disease ◽

Organ Cultures ◽

Growth Of A Variety ◽

Normal Human ◽

Fetal Intestine ◽

Scanning Electron

It has been reported that explants of human fetal intestine can be maintained in culture for up to 21 days in a viable condition and that these organ cultures support the growth of a variety of known viral agents responsible for enteric disease. Scanning electron microscopy (SEM) has been undertaken on several series of these explants to determine their appearance under routine culture conditions.Fresh specimens of jejunum obtained from normal human fetuses were washed, dissected into l-4mm pieces, and cultured in modified Leibowitz L-15 medium at 34° C as previously described. Serial specimens were fixed each day in 3% glutaraldehyde for 90 minutes at room temperature, rinsed, dehydrated, and dried by the CO2 critical point method in a Denton DCP-1 device. Specimens were attached to aluminum stubs with 3M transfer tape No. 465, and one sample on each stub was carefully rolled along the adhesive such that villi were broken off to expose their interiors.

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Lectin Binding Studies on RNA Tumor Virus-Infected Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115250 ◽

1975 ◽

Vol 33 ◽

pp. 326-327

Author(s):

D. C. Hixson

Keyword(s):

Binding Sites ◽

Lectin Binding ◽

Culture Conditions ◽

3T3 Cells ◽

Binding Studies ◽

Con A ◽

Microscopic Studies ◽

Tumor Virus ◽

Infected Cells ◽

Cell Culture Conditions

The abilities of plant lectins to preferentially agglutinate malignant cells and to bind to specific monosaccharide or oligosaccharide sequences of glycoproteins and glycolipids make them a new and important biochemical probe for investigating alterations in plasma membrane structure which may result from malignant transformation. Electron and light microscopic studies have demonstrated clustered binding sites on surfaces of SV40-infected or tryp- sinized 3T3 cells when labeled with concanavalin A (con A). No clustering of con A binding sites was observed in normal 3T3 cells. It has been proposed that topological rearrangement of lectin binding sites into clusters enables con A to agglutinate SV40-infected or trypsinized 3T3 cells (1). However, observations by other investigators have not been consistent with this proposal (2) perhaps due to differences in reagents used, cell culture conditions, or labeling techniques. The present work was undertaken to study the lectin binding properties of normal and RNA tumor virus-infected cells and their associated viruses using lectins and ferritin-conjugated lectins of five different specificities.

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Neutrophil migration through in vitro interstitial matrix

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124872 ◽

1992 ◽

Vol 50 (1) ◽

pp. 894-895

Author(s):

J. Roemer ◽

S.R. Simon

Keyword(s):

Extracellular Matrix ◽

Smooth Muscle ◽

Cell Migration ◽

Smooth Muscle Cells ◽

Inflammatory Cell ◽

Neutrophil Migration ◽

Culture Conditions ◽

Aortic Smooth Muscle ◽

Specific Culture

We are developing an in vitro interstitial extracellular matrix (ECM) system for study of inflammatory cell migration. Falcon brand Cyclopore membrane inserts of various pore sizes are used as a support substrate for production of ECM by R22 rat aortic smooth muscle cells. Under specific culture conditions these cells produce a highly insoluble matrix consisting of typical interstitial ECM components, i.e.: types I and III collagen, elastin, proteoglycans and fibronectin.

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Ultrastructural Study of a differentiating human colon carcinoma cell line

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158583 ◽

1990 ◽

Vol 48 (3) ◽

pp. 208-209

Author(s):

Sylvie Polak-Charcon ◽

Mehrdad Hekmati ◽

Yehuda Ben Shaul

Keyword(s):

Cell Line ◽

Morphological Changes ◽

Secretory Granules ◽

Human Colon ◽

Cell Types ◽

Culture Conditions ◽

Morphological Evidence ◽

Human Colon Carcinoma Cell ◽

Colon Cell

The epithelium of normal human colon mucosa “in vivo” exhibits a gradual pattern of differentiation as undifferentiated stem cells from the base of the crypt of “lieberkuhn” rapidly divide, differentiate and migrate toward the free surface. The major differentiated cell type of the intestine observed are: absorptive cells displaying brush border, goblet cells containing mucous granules, Paneth and endocrine cells containing dense secretory granules. These different cell types are also found in the intestine of the 13-14 week old embryo.We present here morphological evidence showing that HT29, an adenocarcinoma of the human colon cell line, can differentiate into various cell types by changing the growth and culture conditions and mimic morphological changes found during development of the intestine in the human embryo.HT29 cells grown in tissue-culture dishes in DMEM and 10% FCS form at late confluence a multilayer of morphologically undifferentiated cell culture covered with irregular microvilli, and devoid of tight junctions (Figs 1-3).

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