scholarly journals SPORULATION IN DISTILLED WATER

1953 ◽  
Vol 36 (5) ◽  
pp. 601-606 ◽  
Author(s):  
Joan F. Powell ◽  
J. R. Hunter
Keyword(s):  
Solid Material ◽  
Distilled Water ◽  
Vegetative Cells ◽  
Sporulation Process ◽  
Number Of Cells

Spores are formed when vegetative cells of sporing aerobes are shaken with distilled water at 37°. These spores are derived from the small number of cells which survive lysis. The sporulation process involves increase and concentration of solid material in the cell, and is achieved at the expense of the products of lysis of 80 to 90 per cent of the resuspended cells.

scholarly journals Removal of Copper Ions from Aqueous Solution by Bentonite Clay Applied in Soil in Leaching Columns

2018 ◽  
Vol 10 (10) ◽  
pp. 360
Author(s):  
Gilvanise Alves Tito ◽  
Lúcia Helena Garófalo Chaves ◽  
Hugo Orlando Carvallo Guerra ◽  
Josely Dantas Fernandes ◽  
Iêde de Brito Chaves
Keyword(s):  
Copper Ions ◽  
Bentonite Clay ◽  
Solid Material ◽  
Atomic Absorption Spectrophotometry ◽  
Experimental Unit ◽  
Distilled Water ◽  
Copper Leaching ◽  
Vertical Support ◽  
Potential Risks ◽  
Leaching Columns

The objective of this research was to evaluate the effect of bentonite applied in soil, on the removal of copper (Cu) from aqueous solutions, in leaching columns. The experiment was carried out at laboratory using leaching columns filled with 4 kg of soil mixed with bentonite according to treatments B0, B30, B60 and B90, that is, 0; 30; 60 and 90 t ha-1 of bentonite. Each leaching column (experimental unit) was constituted of a PVC tube, with 0.10m of diameter and 0.50m height sectioned in two 0.20 m rings (10-30 cm and 30-40 cm) and one, on the top, of 0.10 m high, reserved for a hydraulic head of 0.08 m. The columns were placed in a vertical support and saturated with distilled water by capillary ascension. Then percolation began, passing through the column five volumes of pores (initially four liters of water contaminated with 1000 mg of Cu and afterwards one liter of distilled water). Ten leached aliquots of 0.5 volume of pores were collected and stored in polypropylene flasks in a refrigerator for quantification of copper (Cu) by atomic absorption spectrophotometry. At the end of the tests, the solid material contained in each ring was collected and the Cu concentration determinated. Increasing doses of bentonite increased Cu retention in soil; Cu was more retained in the surface layer in all treatments; there was no copper leaching from the columns with 60 and 90 t ha-1 of bentonite application, indicating that all copper was retained in the soil avoiding thus potential risks for groundwater contamination.

scholarly journals Histopathological Effects of Carbamazepine on The Reproductive System of Male Rats

2021 ◽  
Vol 26 (2) ◽  
Author(s):  
HAYDER ALAA
Keyword(s):  
Leydig Cells ◽  
Small Diameter ◽  
Male Rats ◽  
Control Group ◽  
Distilled Water ◽  
Pathological Changes ◽  
Adult Rats ◽  
Histopathological Effects ◽  
Carbamazepine Concentration ◽  
Number Of Cells

 This research aims to identify the effect of carbamazepine on genital tissues of male rats.  In this experiment (20) male from adult rats were randomly assigned to 2 groups, Each group comprises (10) animals. Control group  gavage with distilled water, First group  gavage carbamazepine concentration (30) mg/kg of body weight. After 45 days, genitals eradicated for the purpose of textile on study them, Histological examination showed pathological changes in the occurrence of the testis in (T1) represented by its small diameter tubular deferens Also, the number of cells formed for sperm cells and spermatid and leydig cells has been reduced and cells for Spermatogonia get necrosis of the facility.

scholarly journals EXOPOLYSACCHARIDE SYNTHESIS PRODUCTIVITY BY BACILLUS MUCILAGINOSUS DEPENDING ON THE NITROGEN SOURCE AND ORIGIN OF INOCULUM

2015 ◽  
Vol 21 ◽  
pp. 12-17
Author(s):  
I. M. Malinovska
Keyword(s):  
Nitrogen Source ◽  
Culture Medium ◽  
Physiological State ◽  
Bacterial Biomass ◽  
Extracellular Polysaccharide ◽  
Potassium Nitrate ◽  
Bacillus Mucilaginosus ◽  
Vegetative Cells ◽  
Polysaccharide Synthesis ◽  
Sporulation Process

It was established that Bacillus mucilaginosus C-3 requires introduction of nitrogen sourceinto the culture medium in form of nitrate as themost optimal for maximal accumulation of bacterial biomass and sporulation process. Introduction of the ammonium form was less efficient. It was shown that the intensity of nitrogensource use by B. mucilaginosus is highly depended on the physiological state of the inoculum cells. At sowing of spore inoculum theoptimal concentration of potassium nitrate was2.5 g/l resulting in 1010 cells/ml, while under theuse of vegetative cells the optimal concentrationof potassium nitrate was 1.0 g/l leading to theaccumulation of 109 cells/ml.Use of spore inoculum had ensured themaximum productivity of extracellular polysaccharide synthesis. With the higher number ofB. mucilaginosus subcultures in a vegetativestate the efficiency of the exopolysaccharidesynthesis has decreased: after the second passage — by 20.0 %, after the fourth — by 56.5 %,after the sixth — at 127.8 %. After eighth passage the culture loses its ability to synthesizepolysaccharide, especially on the medium withthe N : C ratio 1 : 3 and resume this ability onlyafter sporulation and the significant increase ofthe N : C ratio.

scholarly journals Differentiation of vegetative cells into spores: a kinetic model applied toBacillus subtilis

2018 ◽  
Author(s):  
Emilie Gauvry ◽  
Anne-Gabrielle Mathot ◽  
Olivier Couvert ◽  
Ivan Leguérinel ◽  
Matthieu Jules ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Vegetative Cell ◽  
Bacterial Population ◽  
Fluorescent Protein ◽  
Raw Materials ◽  
Bacterial Species ◽  
Vegetative Cells ◽  
Sporulation Process ◽  
Time Required ◽  
Over Time

AbstractBacterial spores are formed within vegetative cells as thick-walled bodies resistant to physical and chemical treatments which allow the persistence and dissemination of the bacterial species. Spore-forming bacteria are natural contaminants of food raw materials and sporulation can occur in many environments from farm to fork. In order to predict spore formation over time, we developed a model that describes both the kinetics of growth and the differentiation of vegetative cells into spores. The model includes a classical growth model with the addition of only two sporulation-specific parameters: the probability of each vegetative cell to sporulate, and the time needed to form a spore once the cell is committed to sporulation. The growth-sporulation model was evaluated using the spore-forming, Gram positive bacterium,Bacillus subtilisand the biological meaning of the sporulation-specific parameters was validated using a derivative strain that produces the green fluorescent protein as a marker of sporulation initiation. The model accurately describes the growth and the sporulation kinetics in different environmental conditions and further provides valuable, physiological information on the temporal abilities of vegetative cells to differentiate into spores.ImportanceThe growth-sporulation model we developed accurately describes growth and sporulation kinetics. It describes the progressive transition from vegetative cells to spores with sporulation parameters which are meaningful and relevant to the sporulation process. The first parameter is the mean time required for a vegetative cell to differentiate into a spore (i.e. the duration of the sporulation process). The second sporulation parameter is the probability of each vegetative cell forming a spore over time. This parameter assesses how efficient the sporulation process is, how fast vegetative cells sporulate and how synchronous the bacterial population is for sporulation. The model constitutes a very interesting tool to describe the growth and the sporulation kinetics in different environmental conditions and it provides qualitative information on the sporulation of a bacterial population over time.

GLYCOPEPTIDE SYNTHESIS DURING SPORULATION OF BACILLUS MEGATERIUM

1967 ◽  
Vol 13 (12) ◽  
pp. 1615-1620 ◽  
Author(s):  
William E. Gledhill
Keyword(s):  
Cell Wall ◽  
Stationary Phase ◽  
Bacillus Megaterium ◽  
Wall Material ◽  
Amino Sugars ◽  
Sporulation Medium ◽  
Cell Wall Material ◽  
Early Stationary Phase ◽  
Vegetative Cells ◽  
Number Of Cells

The present study was initiated to determine the amount of glycopeptide synthesized during sporulation of Bacillus megaterium. The glycopeptide fraction was isolated quantitatively from vegetative cells, sporulated cells, and free spores, and then assayed for amino sugars. The yields of glycopeptide hexosamine (GPH) in these preparations were compared on the basis of number of cells. During the early stationary phase of cultural growth, cells continued to synthesize cell wall material even though they did not divide or increase in size significantly. In the sporulation medium GPH synthesis was synchronized with the development of the endospore within the bacilli. During this period GPH formation occurred at an increased rate. Synthesis terminated as free spores were liberated from their sporangia. The total amount of GPH synthesized in the sporulating bacilli could be accounted for in the cleaned, free spores.

CALCIUM REVERSAL OF THE HEAT SUSCEPTIBILITY AND DIPICOLINATE DEFICIENCY OF SPORES FORMED "ENDOTROPHICALLY" IN WATER

1960 ◽  
Vol 6 (2) ◽  
pp. 213-224 ◽  
Author(s):  
Samuel H. Black ◽  
Tadayo Hashimoto ◽  
Philipp Gerhardt
Keyword(s):  
Gamma Radiation ◽  
Bacillus Cereus ◽  
Calcium Ions ◽  
Dipicolinic Acid ◽  
Distilled Water ◽  
Vegetative Cells ◽  
Low Concentration

Spores of Bacillus cereus strain terminalis formed "endotrophically" by transferring granular vegetative cells to distilled water were found to be relatively susceptible to heat and deficient in dipicolinic acid. Calcium ions alone, added in low concentration shortly after the cells were placed in water, could completely relieve these abnormalities. Although the water-formed spores were sensitive to heat, they were as fully resistant as normal spores to gamma radiation or phenol.

scholarly journals NON-INVOLVEMENT OF LYSIS DURING SPORULATION OF BACILLUS MYCOIDES IN DISTILLED WATER

1954 ◽  
Vol 37 (3) ◽  
pp. 401-409 ◽  
Author(s):  
Jerome J. Perry ◽  
J. W. Foster
Keyword(s):  
Cell Growth ◽  
Vegetative Cell ◽  
Direct Conversion ◽  
Resistant Cell ◽  
Distilled Water ◽  
Bacillus Mycoides ◽  
Vegetative Cells ◽  
Heat Resistant ◽  
Negative Results

Washed vegetative cells of Bacillus mycoides obtained and treated under specified conditions have been found to sporulate when shaken in distilled water under specified conditions. Within limitations of the methods, a heat-resistant cell (spore) is produced for each heat-sensitive vegetative cell present initially. Several different experiments designed to detect massive lysis and cell growth during sporulation in distilled water yielded uniformly negative results. Evidence is furnished for the conclusion that a freshly formed spore (heat-resistant cell) weighs considerably less than its progenitor vegetative cell. The observed results are most satisfactorily explained as a direct conversion of a vegetative cell to a spore.

Biophysical Measurement of Molecular Weight of Foot-and-Mouth Disease RNA Fragments

1974 ◽  
Vol 32 ◽  
pp. 262-263
Author(s):  
Sydney S. Breese ◽  
Howard L. Bachrach
Keyword(s):  
Chemical Properties ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Distilled Water ◽  
Bovine Plasma ◽  
Mouth Disease Virus ◽  
Foot And Mouth ◽  
Carbon Coated ◽  
Rna Fragments ◽  
Physical And Chemical

Continuing studies on the physical and chemical properties of foot-and-mouth disease virus (FMDV) have included electron microscopy of RNA strands released when highly purified virus (1) was dialyzed against demlneralized distilled water. The RNA strands were dried on formvar-carbon coated electron microscope screens pretreated with 0.1% bovine plasma albumin in distilled water. At this low salt concentration the RNA strands were extended and were stained with 1% phosphotungstic acid. Random dispersions of strands were recorded on electron micrographs, enlarged to 30,000 or 40,000 X and the lengths measured with a map-measuring wheel. Figure 1 is a typical micrograph and Fig. 2 shows the distributions of strand lengths for the three major types of FMDV (A119 of 6/9/72; C3-Rezende of 1/5/73; and O1-Brugge of 8/24/73.

Freeze-fracture, freeze-etch complementary pairs of virus-infected cells reveal value of etching even when relatively high concentrations of cryoprotectants are used

1978 ◽  
Vol 36 (2) ◽  
pp. 136-137
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe
Keyword(s):  
Plant Tissue ◽  
Phosphate Buffer ◽  
Infected Plant ◽  
Freeze Fracture ◽  
Distilled Water ◽  
Virus Infected Plant ◽  
Infected Cells ◽  
High Concentrations

It has been assumed by many involved in freeze-etch or freeze-fracture studies that it would be useless to etch specimens which were cryoprotected by more than 15% glycerol. We presumed that the amount of cryoprotective material exposed at the surface would serve as a contaminating layer and prevent the visualization of fine details. Recent unexpected freeze-etch results indicated that it would be useful to compare complementary replicas in which one-half of the frozen-fractured specimen would be shadowed and replicated immediately after fracturing whereas the complement would be etched at -98°C for 1 to 10 minutes before being shadowed and replicated.Standard complementary replica holders (Steere, 1973) with hinges removed were used for this study. Specimens consisting of unfixed virus-infected plant tissue infiltrated with 0.05 M phosphate buffer or distilled water were used without cryoprotectant. Some were permitted to settle through gradients to the desired concentrations of different cryoprotectants.

Comparison of Acrylamide and Agar Gels by Freeze-Etching

1977 ◽  
Vol 35 ◽  
pp. 606-607
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe
Keyword(s):  
Electron Microscope ◽  
Sodium Hydroxide ◽  
Sodium Hypochlorite ◽  
Chromic Acid ◽  
Distilled Water ◽  
Thin Sheets ◽  
Acid Cleaning ◽  
Agar Gels ◽  
Freeze Etching ◽  
Water Cut

Thin sheets of acrylamide and agar gels of different concentrations were prepared and washed in distilled water, cut into pieces of appropriate size to fit into complementary freeze-etch specimen holders (1) and rapidly frozen. Freeze-etching was accomplished in a modified Denton DFE-2 freeze-etch unit on a DV-503 vacuum evaporator.* All samples were etched for 10 min. at -98°C then re-cooled to -150°C for deposition of Pt-C shadow- and C replica-films. Acrylamide gels were dissolved in Chlorox (5.251 sodium hypochlorite) containing 101 sodium hydroxide, whereas agar gels dissolved rapidly in the commonly used chromic acid cleaning solutions. Replicas were picked up on grids with thin Foimvar support films and stereo electron micrographs were obtained with a JEM-100 B electron microscope equipped with a 60° goniometer stage.Characteristic differences between gels of different concentrations (Figs. 1 and 2) were sufficiently pronounced to convince us that the structures observed are real and not the result of freezing artifacts.

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