Showing papers on "Growth medium published in 1969"
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TL;DR: The shape and the osmotic susceptibility of the protoplasts of this organism appeared to depend on the growth conditions, and the presence of a more rigid membranous structure in cells which have been exposed to a low environmental pH during growth.
Abstract: Bacillus subtilis contained at least five phospholipids, four of which have been isolated and identified as a polyglycerol phospholipid, probably cardiolipin, phosphatidylglycerol, phosphatidylethanolamine, and lysylphosphatidylglycerol. Further purification of the latter phosphoglyceride was obtained by high-voltage electrophoresis, and it was shown that this treatment removed amino acid-containing, nonlipidic material from the phosphoglyceride. This associated material, which is not covalently linked to the lipid, gave rise to minor amounts of a number of amino acids, other than lysine, in acid hydrolysates of the lysylphosphatidylglycerol. The phospholipid composition of B. subtilis appeared to depend on the growth conditions. Addition of glucose to the medium lowered the pH during growth; this was accompanied by an increase in the amount of lysylphosphatidylglycerol and a decrease in the phosphatidylglycerol content, when compared with growth at neutral pH. The amount of the other phospholipids and the total amount of phospholipid remained constant under the different conditions. The shape and the osmotic susceptibility of the protoplasts of this organism appeared to depend on the growth conditions. Cells harvested from a neutral growth medium gave spherical protoplasts which lysed rapidly, whereas cells grown in an acidic medium maintained their rod-shaped form to a great extent after the cell wall had been removed, even after being suspended in a hypotonic medium. The latter observation suggests the presence of a more rigid membranous structure in cells which have been exposed to a low environmental pH during growth.
139 citations
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TL;DR: The activities of two glutamate dehydrogenases, one requiring NAD and the other specific for NADP, and of aspartate and alanine amino transferases varied during growth as a function of the stage of the life cycle and of the growth medium, finding no clear correlation between the activities of these enzymes and conidiation of this fungus.
Abstract: SUMMARY: Asexual sporulation of Aspergillus niger occurred in submerged culture in a liquid minimal medium without added nitrogen, in low ammonium-N concentrations, and in a wide range of nitrate-N concentrations. Ammonium salts containing more than 48 mg. atom N/l. were inhibitory to conidiation. Most amino acids overcame the ammonium inhibition of conidiation when added to an ammonium nitrate medium. Glyoxylate and several intermediates of the tricarboxylic acid (TCA) cycle also promoted conidiation in the presence of ammonium. Changes in the medium of conidiating and non-conidiating cultures were examined with respect to nitrogen and glucose concentrations, dry weight and pH value. The activities of two glutamate dehydrogenases, one requiring NAD and the other specific for NADP, and of aspartate and alanine amino transferases varied during growth as a function of the stage of the life cycle and of the growth medium. There was no clear correlation between the activities of these enzymes and conidiation of this fungus.
66 citations
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TL;DR: A direct relationship between the presence of anti-protease factors and growth of cells was shown with a wide variety of sera from different animals and man and the growth-promoting quality of serum was shown to be related to its titer against these enzymes.
49 citations
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TL;DR: It was found that the phospholipids of secondary chick fibroblasts, labeled with 32 PO 4 or 14 C-choline, were continuously released into the growth medium, and these lipid-protein complexes could be fractionated by gel filtration into two fractions.
48 citations
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TL;DR: Effect of salinity on malate dehydrogenase activity was studied and a new, third isoenzyme was located in the cytoplasmic fraction of plants grown in media salinated with NaCl to 1 atmosphere.
Abstract: Effect of salinity on malate dehydrogenase activity was studied.Pea root tips contain 2 different malate dehydrogenases. One is located in the particulate, mitochondrial fraction, the other in the soluble, cytoplasmic fraction. Both can act when coupled with either NAD or NADP.Growing plants in Na(2)SO(4) salinated medium did not affect the pattern of the malate dehydrogenases in the root tips. Growing plants in NaCl salinated media resulted in the appearance of a new, third isoenzyme. This new isoenzyme was located in the cytoplasmic fraction.Salinity of both types, when present in growth medium, induced increases in the NADP coupled activity of the mitochondrial malate dehydrogenase. The NAD coupled activity, however, was depressed except in the cytoplasmic fraction of plants grown in media salinated with NaCl to 1 atmosphere. Addition of either of the salts to assay media of enzymes, isolated from plants grown in non salinated substrate, did not have any significant effect.
39 citations
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TL;DR: The use of enzymatic casein hydrolysate, oxytocin, or vasopressin rather than ammonia as nitrogen source for growth of strain 23 depressed the incorporation of 2-methylbutyrate into isoleucine, appearing to be an important reaction in the rumen.
Abstract: Microorganisms in ruminal ingesta and pure cultures of anaerobic ruminal bacteria of different physiological and morphological groups incorporated (14)C from labeled 2-methylbutyrate during growth. The radioactivity was incorporated mainly into lipid and protein. Isoleucine was the only labeled amino acid found in acid hydrolysates of protein from either pure or mixed cultures. Radioactivity in isoleucine synthesized from 2-methylbutyrate-1-(14)C was entirely in carbon-2. Thus, the carboxylation of 2-methylbutyrate is a pathway for synthesis of isoleucine different from that operative in many aerobic and facultative microorganisms. The specific activity of isoleucine from 2-methylbutyrate by Bacteroides rumminicola 23 increased with higher concentrations of 2-methylbutyrate (2.6 to 44 x 10(-5)m) in the growth medium. At the highest concentration, the specific activity of isoleucine synthesized was 40% of the specific activity of the 2-methylbutyrate in the growth medium. The use of enzymatic casein hydrolysate, oxytocin, or vasopressin rather than ammonia as nitrogen source for growth of strain 23 depressed the incorporation of 2-methylbutyrate into isoleucine. Synthesis of isoleucine from 2-methylbutyrate appears to be an important reaction in the rumen.
38 citations
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TL;DR: The spheroplasts do not require a stabilizing medium to keep them from rupturing, and they are stable for 2 to 3 hr when exposed to a temperature of 65 C, and the membrane content of the cell increases with age of culture, and it is unaffected by composition of the growth medium.
Abstract: Spheroplasts were prepared by lysozyme digestion of the cell wall and ruptured by suspension in 0.15 m NaCl, followed by centrifugation at 30,900 x g for 35 min, and by a final suspension in 0.05 m NaCl for 12 to 16 hr at 5 C. The membrane ghosts were washed four times in tris(hydroxylmethyl)aminomethane (Tris) magnesium buffer and once in distilled water. The intact membranes resembled empty sacs with narrow slits in which the cytoplasm was extruded. A 92% recovery of cell membrane was obtained with all membrane preparations. The spheroplasts do not require a stabilizing medium to keep them from rupturing, and they are stable for 2 to 3 hr when exposed to a temperature of 65 C. The membrane content of the cell increases with age of culture (mid-log, 16.5%; late-log, 17.0%; and stationary, 17.6%) and temperature of growth (55 C, 16.5%; and 65 C, 17.8%), and it is unaffected by composition of the growth medium. The ratio of the protein to lipid content of the membrane increases with the complexity of the medium, age of culture (mid-log, 3.65; late-log, 3.91; and stationary, 4.15), and temperature of growth (55 C, 3.65; and 65 C, 5.22). The ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) content of the membranes was 9.0 to 13.7% and 0.3 to 0.8%, respectively. Reducing sugar (determined as glucose) amounts to 0.9 to 1.0% of the membrane weight and did not significantly vary for the different membrane preparations. Medium composition, age of culture, and temperature of growth have no significant effect on the amount of each amino acid in the membrane. Aspartic acid, glutamic acid, alanine, leucine, and lysine are present in the greatest amount and represent 12.9 to 14.1%, 10.4 to 11.3%, 9.6 to 10.3%, 7.7 to 8.8%, and 7.6 to 8.5% of the membrane peptide, respectively. Prior to the rupture of the spheroplasts, 25.0, 15.7, and 50.0% of the protein, RNA, and DNA, respectively, is lost. In potassium phosphate-magnesium buffer without sucrose, 90% of the protein and RNA and 95% of the DNA is lost from the spheroplasts. In the presence of sucrose, the leakage of RNA and DNA is similar to that observed for spheroplasts suspended in Tris magnesium buffer; however, the leakage of protein is 2.4 times greater.
30 citations
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TL;DR: Development and maintenance of spore motility occurred even at very low oxygen tensions but was probably dependent upon an intact respiratory system and less sensitive to lack of oxygen, respiratory inhibitors, and a factor formed during growth than was sporangial development.
Abstract: Aphunomgces astaci, Saprolegniaceae, the crayfish plague parasite, grows well in a buffered peptone - glucose - mineral salt medium but does not normally produce spores during growth in this medium. Sporulation is, however, easily induced by transfer to pond water. None of the components of the complete medium inhibited sporulation more than partly when tested solely or in combinations. Neither lack of oxygen, high carbon dioxide concentrations, nor osmotic phenomena could satisfactority exlpain the absence of spore formation in the complete medium. In a peptone - glucose growth medium low in phosphate and metal salts a sporulation inhibiting factor was formed by the mycelium. In this medium both good growth and good spore production could, however, occur simultaneously and spore production was here stimulated by a reduction in the oxygen tension. Liberation of formed spores into the medium was inhibited by mineral salts. It was less sensitive to lack of oxygen, respiratory inhibitors, and a factor formed during growth than was sporangial development. Development and maintenance of spore motility occurred even at very low oxygen tensions but was probably dependent upon an intact respiratory system.
29 citations
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TL;DR: The specific activities of Lactobacillus casei extracts increase during the period of logarithmic growth of the culture and decrease during the stationary phase, which may indicate a rapid rate of synthesis since it is prevented by actinomycin D and chloramphenicol.
29 citations
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TL;DR: The experimental results support the generally accepted conclusion that bacterial catalase acts in protecting the organism from H2O2, and resulted in the development of H 2O2 resistance.
Abstract: SUMMARY: The effect of hydrogen peroxide on the growth of Salmonella typhimurium lt2 in a mineral glucose medium was investigated. The H2O2 produced a lag period, the duration of which increased as the concentration of H2O2 in the medium was increased from 1 to 60 μg./ml. Growth subsequent to the lag period proceeded at the normal growth rate at concentrations of H2O2 as high as 30 μg./ml. Storage of H2O2 in the sterile growth medium resulted in a disappearance of H2O2 with a half-life of about 48 hr. The disappearance of H2O2 because of reaction with glucose resulted in proportionate decreases in the growth inhibitory action of the medium. Salmonella typhimurium destroyed H2O2 rapidly (half-time = 60 min.)—an effect attributed largely to bacterial catalase. The catalatic activity of the bacteria was decreased or eliminated by boiling or by treatment with cyanide. The growth of the bacteria in H2O2 resulted in the development of H2O2 resistance. By subculturing the wild type lt2 in medium containing successively higher H2O2 concentration, a resistant strain designated lt2 p was isolated which grew in the presence of H2O2 concentrations that were completely inhibitory to the wild type.
The experimental results support the generally accepted conclusion that bacterial catalase acts in protecting the organism from H2O2. It is pointed out that in biological media H2O2 readily forms adducts with many compounds, including carbonyls, amino acids and thymine. Consequently, the inhibitory effects of H2O2, especially in studies involving auxotrophs, may be partly or wholly due to the peroxide adduct rather than ‘free’ H2O2.
28 citations
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TL;DR: Gymnoplasts or protoplasts, produced from bacilli exposed to low p H values, were found not to conform to the formulations on “protoplasts” given in 1958 by 13 authors.
Abstract: Addition of glucose to the medium in which Bacillus subtilis was grown lowered the p H and increased the amount of lysylphosphatidylglycerol relative to the phosphatidylglycerol content of the membrane fraction. This change in phospholipid composition was accompanied by changes in the shape and behavior of the gymnoplasts obtained by cell wall removal with lysozyme. These gymnoplasts appeared to retain most of their original cell shape and internal organization, often with preservation of the mesosomes. Cells harvested from neutral growth medium gave the usual spherical gymnoplasts. In a hypotonic medium, the spherical gymnoplasts lysed rapidly, whereas the rod-like gymnoplasts lost only part of their cell content while showing a tendency to preserve the original shape. This type of gymnoplast could not be produced from cells grown in neutral medium by simply raising the magnesium concentration. When this was done the gymnoplasts assumed bizarre shapes; they became compact and susceptible to the tonicity of the medium. Gymnoplasts or protoplasts, produced from bacilli exposed to low p H values, were found not to conform to the formulations on “protoplasts” given in 1958 by 13 authors. Cells exposed to a low environmental p H during growth seemed to possess a more rigid membrane structure than cells grown at neutral p H. Images
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TL;DR: Variation in the composition of the metabolic pool of heated cells occurred during the early lag phase and may be as a result of damage to the cytoplasmic membrane with resulting loss of permeability control.
Abstract: Staphylococcus aureus cells which had been heated at 50 or 60° were transferred to various growth media and intracellular ribonucleic acid (RNA), deoxyribonucleic acid (DNA) and amino acids were measured during the lag phase of growth. The duration of the lag phase depended on the temperature to which the cultures had been subjected, and was longest following storage at 60°. RNA synthesis occurred almost immediately on placing treated cells in a growth medium, but at a slower rate than with unheated cells. Variation in the composition of the metabolic pool of heated cells occurred during the early lag phase and may be as a result of damage to the cytoplasmic membrane with resulting loss of permeability control.
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TL;DR: The polyamines, spermine and trimethylenediamine, as well as erythritol and sucrose, exerted some protective action against the effects of cold but not uniformly for all strains studied.
Abstract: The effect of low, nonfreezing temperatures on the viability of five strains of Chromobacterium violaceum was studied. The viability of cultures grown at 30 C was determined after exposure to various diluents held at 0 to 2 C. A culture diluted at its growth temperature served as the control. Cells of strain N were most sensitive in the early part of the exponential phase of growth. Cells of strains 252 and 341 were most sensitive in the late exponential, early stationary phase of growth. Cells of strain 9 showed greatest loss of viability during the maximal stationary phase. Strain 69 was completely resistant throughout its growth cycle to cold injury. Cell viability was much greater in buffered salts solution than in distilled water, broth, or physiological saline, whether cultures were diluted at room temperature or in the cold. The proportion of cells surviving after exposure to cold, however, was the same regardless of the composition of the diluent. Loss of viability was progressive at 0 to 2 C and reached a maximum after 2 hr. There was no loss of viability of cells exposed to 20 C, but there was some loss at 12 C. Strain 341 cultivated at 15 C was much less sensitive to 0 to 2 C than when it was cultivated at 30 C. The composition of the growth medium seemed to have no effect on the survival of cells exposed to cold. The polyamines, spermine and trimethylenediamine, as well as erythritol and sucrose, exerted some protective action against the effects of cold but not uniformly for all strains studied.
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TL;DR: The addition of yeast extract and the use of shaking increase cell crop yield of group A streptococci grown in Todd-Hewitt broth 4 to 5 times that normally obtained.
Abstract: The addition of yeast extract and the use of shaking increase cell crop yield of group A streptococci grown in Todd-Hewitt broth 4 to 5 times that normally obtained.
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08 Jan 1969
TL;DR: In this paper, a disclosure is directed to the production of the enzyme glucoamylase and ammonium hydroxide or ammonia gas is introduced into the growth medium to provide a source of ammonia and to maintain the pH of medium at the level where optimum growth of the microorganisms occurs.
Abstract: The disclosure is directed to the production of the enzyme glucoamylase. During the growth of glucoamylase producing microorganisms, ammonium hydroxide or ammonia gas is introduced into the growth medium to provide a source of ammonia and to maintain the pH of medium at the level where optimum growth of the microorganisms occurs.
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TL;DR: The results show that the role of nucleotides, especially IMP, is not limited to recovery from exposure to extreme salt effects, but also applies to growth in the continuing presence of quite different chemical stress conditions.
Abstract: The study of chemical stress tolerance in a Penicillium mutant was continued using KCl- and H(3) BO(3) -saturated glucose peptone broth as a basic growth medium. Growth was completely restricted to the mutant. Variations were the presence or absence of inosine-5'-phosphate (inosinic acid, IMP) and choice of carhohydrate which was substituted for glucose. All six monosaccharides used-three hexoses, three pentoses - were essentially equivalent hence data are presented only for D-glucose and D-xylose. The other carbohydrates, sucrose, lactose, maltose and starch differed in their suitability as carbon sources. In the presence of the nionosaccharides the mutant can grow both in KCl and H(3) BO(3) media, but growth rates are greatly enhanced by IMP. Boric acid blocked sporulation under all conditions. KCl permitted spores of abnormal color to form without IMP, whereas spores of normal green color appeared in its presence. Media containing H(3) BO(3) and disaccharides or starch supported no growth, but addition of IMP stimulated growth without sporulation. In KCl media sucrose alone among the disaccharides and starch permit limited growth without IMP, but the nucleotide is required for sporogenesis. These results show that the role of nucleotides, especially IMP, is not limited to recovery from exposure to extreme salt effects, but also applies to growth in the continuing presence of quite different chemical stress conditions.
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TL;DR: This isolation method proved to be one which permits identification of the Chaetomium species without further culturing.
Abstract: It was shown that Chaetomium was isolated from four types of soil; Cinebar, Ephrata, Milville, and quartz sand, more frequently when using alcohol agar as the growth medium than it (Chaetomium) was isolated from these soils when using either Czepak's-Dox agar or peptone-dextrose agar plus rose bengal and streptomycin This isolation method proved to be one which permits identification of the Chaetomium species without further culturing