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PubMed1999

[Different protein forms of purple membrane produced by Halobacterium halobium under various nutritional condition].

The extremely halophilic bacterium, purple membrane producing Halobacterium halobium strain R1 were cultured in four liquid media which consist of different constituents. After the purple membrane is harvested by ultracentrification and purified by sucrose density gradient ultracentrification, and run on SDS-PAGE, the result of Coomassie blue staining showed different bR protein forms: three bands with molecule weight ranging from 26.0 to 27.5 kD in peptone medium, while only one band with MW 26.0 kD in other three media-complex, synthetic and artificial seawater media, which corresponded to the mature form in peptone medium. The result of Western blotting not only confirmed the different protein forms of Coomassie blue staining in the four media, but also gave additional bands that Coomassie blue can not detect due to its lower sensitivity: 1) in the complex, synthetic and artificial seawater media, a faint 28.0 kD band existed, while in the peptone medium it did not exist; and 2) in the four media, it appeared that a faint 23.0-24.0 kD band exited. The different bR protein forms of purple membrane which result from the difference of nutritional constituents in these four media might be caused by different precursor processing enzymes or different activities of precursor processing enzyme(s) under these different nutritional conditions.

Culture Media↗

PubMed1991

Action of DL-alpha-difluoromethyl ornithine on Acanthamoeba culbertsoni.

The multiplication of A. culbertsoni in the peptone medium was not inhibited by 10-20 mM concentration of alpha-difluoromethyl ornithine (DMFO) while a partial and transient inhibition of cell multiplication was observed by 10-20 mM DFMO in proteose peptone, yeast extract, glucose (PYG) medium. Ornithine decarboxylase (ODC) activity in the cells and cell free extracts was strongly inhibited by DFMO, excluding enzyme refractoriness and impermeability of cells for DFMO as the possible causes of DFMO resistance. The presence of polyamines in the peptone and PYG media as well as uptake of polyamines by the amoebae has been demonstrated. The growth and multiplication of A. culbertsoni in chemically defined medium was not affected by 1-5 mM DFMO while 10-20 mM DMFO yielded partial inhibition. A lowering of diaminopropane levels and enhancement of spermidine levels was observed in DFMO inhibited cells and level of ODC was drastically reduced in the inhibited cultures. Uptake of polyamines from the growth media may partly account for DFMO resistance of A. culbertsoni. Alternative mechanisms for DFMO resistance are indicated.

Acanthamoeba↗

PubMed1976

New media and their advantages in the production of suspended cells and foot--and--mouth disease virus.

The problems related to the use of serum in cell culture are reviewed. The possibility of substituting the serum with peptones has already been shown. Different peptones have been tested: one of the best is a peptone obtained from meat and casein pepsin pancreatically digested. BHK 21/13 cells were cultivated in serum-free media for 35 passages. The 0.81 cultures without automatic pH control had a cycle length of 3 days; starting with concentrations of 0.4 X 10(6) cells/ml, concentrations higher than 3 X 10(6) cells/ml were often obtained. We did not obtain satisfactory results when the volume of cultivation was increased to more than 6 1, perhaps because of different requirements for agitation, pH, O2. It is also necessary to check whether the results obtained up to now are consistent with reference to the source of reagents and cell strain used. The absence of serum in the medium did not influence virus replication when infectivity and complement fixation titers were tested.

Aphthovirus↗

PubMed1990

[Effect of 1 week's administration of prednisone on gastric acid secretion and liberation of gastrin in healthy humans].

In a double-blind, randomized study we examined the effects of an oral administration of prednisone (60 mg/day for 6 days) or placebo on gastric acid output basally (BAO), in response to peptone meals 1%, 2%, 4% and 8%, 500 ml each) and to pentagastrin 6 micrograms/kg s.c. to determine maximal acid output, MAO) and on plasma gastrin levels in 14 healthy volunteers. Gastric acid output was measured by intragastric titration (pH 5.5). For gastrin determination we used a specific radioimmunoassay. Experiments were performed one day (day 0) before giving the drugs and one day (day 7) and one month (day 30) after finishing the treatment. Both groups were comparable in their gastric acid responses on day 0. Six days treatment with prednisone did not significantly alter BAO, MAO and the gastric acid response to peptone and pentagastrin. Also, one month after finishing the treatment there were no significant differences in gastric acid output. Both groups had similar plasma gastrin levels on each day. Prednisone did not significantly alter plasma gastrin levels. We conclude that a six-day treatment with prednisone does not alter BAO, MAO and gastric secretory responses to peptone nor release of gastrin in healthy human volunteers.

Administration, Oral↗

PubMed1989

Diminishing efficacy of octreotide (SMS 201-995) on gastric functions of healthy subjects during one-week administration.

In this study, the pharmacokinetics, efficacy, and tolerability of 25 and 100 micrograms of octreotide given t.i.d. for 7 days subcutaneously were investigated in 12 healthy male subjects. Serum concentrations of the drug were well reproducible within 1 wk. Octreotide significantly raised 24-h median intragastric pH on day 1, but no longer on day 6. Peptone-stimulated gastric acid and volume secretion were markedly less suppressed by octreotide on day 7 compared with day 2. Peptone-stimulated gastrin release was abolished on days 2 and 7, as was peptone-stimulated insulin release. Blood glucose was altered in a biphasic pattern on days 2 and 7. All effects of octreotide were without clear-cut dose-response relationship. A mean half-life of 115 min was calculated. Dose-unrelated side effects (e.g., abdominal cramps, diarrhea, and fatty stools) were registered. In conclusion, octreotide is a powerful inhibitor of gastric acid and volume secretion during acute treatment. Its loss of efficacy during a 1-wk administration may be due to the adaptation of somatostatin receptors and hormonal counterregulation.

Adult↗

PubMed1979

Influence of culture medium of the fatty-acid profile in enteric bacteria.

Enteric bacteria having a high content of cyclopropane fatty acids steeply increase their synthesis when grown on insufficiently propitious culture media (meat-peptone agar or modified Drobot'ko synthetic medium) as compared with bacteria grown under more favourable conditions (meat-peptone broth). Simultaneously, a decrease in monounsaturated fatty acids and increase in palmitic acid are observed. One of the main factors underlying the change in the proportion of fatty acids in bacteria grown on synthetic medium is an increase in medium pH in the process of their growth. Enteric bacteria containing minute amounts/or not containing cyclopropane fatty acids at all (under the experimental conditions used) change their fatty-acid profile little if the culture medium is changed. When grown under insufficiently favourable conditions, these bacteria mainly display an enhanced content of palmitic acid and a lowered content of octadacenoic acid as compared with bacteria grown under more favourable conditions. Of the culture media used, meat-peptone broth, which affords the most favourable conditions for eneteric bacteria growth, is the most suitable medium for obtaining data of taxonomic value.

Culture Media↗

PubMedDate not supplied

[Speroplast behavior in cultures of Thermus ruber].

Spheroplasts spontaneously originating in cultures of Thermus ruber, which are cultivated on potato-peptone media, are capable of growth and multiplication. They may reach 10 mc in diameter. Spheroplasts multiply by budding which can be preceded with inner division or budding; as a result 2--9 and more protoplast bodies are formed under the "envelope" of a spheroplast. Self-reproduction of spheroplasts is most active in a semiliquid potato-meat-peptone medium containing 0.2--0.3 per cent of agar. Microcolonies, which are clusters of spheroplasts in the process of budding, are formed at 45 degrees C in this medium during 1--2 days. Reversion of spheroplasts to rod-like cells occurs if L-lysine and/or DL-alpha-aline are added to the potato-peptone medium. Spheroplasts spontaneously produced by Thermus ruber are similar to the unstable type of L-form in their fine organization and behaviour in cultures.

Cell Division↗

PubMed1984

[Use of different media for growing the producer of the restriction enzyme XBA I].

The possibility of using culture media prepared from local ingredients and intended for growing the producers of restricting enzyme Xba 1 has been demonstrated. The yield of restricting enzyme Xba 1 per g of crude biomass, obtained with the use of peptone-yeast medium prepared from ingredients supplied by Difco Laboratories (USA), has proved to be 4 times greater than that obtained with the use of peptone-yeast medium prepared from local ingredients. At the same time the use of casein-saline medium ensures the yield of the enzyme, similar to that obtained with the use of peptone-yeast medium prepared from ingredients supplied by Difco Laboratories, but with a greater content of nonspecific nucleases.

Culture Media↗

PubMed1983

Fractionation of untreated and inflammatory murine peritoneal macrophages on discontinuous Percoll density gradients.

Peritoneal cells from C57/BL/6J mice untreated or injected with saline, proteose-peptone or Corynebacterium parvum intraperitoneally or Sauton medium or BCG intravenously were fractionated on discontinuous Percoll gradients. Six subsets of macrophages were obtained in all the groups. Injection of BCG and proteose-peptone increased the percentage of heavy density macrophages whereas C. parvum caused an increase in macrophages in the lighter density fractions. The macrophages in all the subsets were tested for their ability to kill L929 target cells and cytochemically for expression of beta-galactosidase. The highest degree of cytotoxicity was found in the higher density subsets, although the other subsets in the C. parvum group were also cytotoxic. There was a marked reduction in beta-galactosidase in macrophages obtained after injection of C. parvum and to a varying degree after injection of BCG, proteose-peptone or saline. Cells which were devoid of enzyme were evenly distributed throughout the subsets. These studies indicate that a certain degree of separation of cytotoxic macrophages can be achieved by density centrifugation, but not of cells containing different amounts of beta-galactosidase.

Animals↗

PubMedDate not supplied

In vitro activity of thienamycin.

The in vitro activity of thienamycin was determined simultaneously in Müller-Hinton broth and peptone broth. Minimum inhibitory and bactericidal concentrations were compared to those of 4 aminoglycosides and 3 cefalosporins. The activity of thienamycin against gram-negative aerobic bacterial was influenced by the media. Peptone broth gave the lowest MICs and MBCs. Concentrations less than or equal to 8 mcg thienamycin/ml peptone broth inhibited 354 out of 382 strains tested.

Aminoglycosides↗

PubMed1997

[The mechanisms of the inhibition of gastric acid secretion induced by intraduodenal amino acids in rats].

We investigated the effect of intraduodenal amino acids (AA) on gastric acid secretion and gastrin release, and possible role of endogenous secretin on this phenomenon in vivo in rats. Intraduodenal administration of mixed AA solution (140 mg/hr, pH6.5) resulted in significant inhibition of gastric acid secretion and gastrin release stimulated by intragastric perfusion of peptone (0.5%). Intravenous infusion of secretin (0.05CU/kg/hr) also inhibited peptone-stimulated gastric acid secretion and gastrin release. Furthermore, the AA-induced suppression of gastric acid secretion was significantly blocked by intravenous injection of rabbit anti-secretin serum. In conclusion, intraduodenal AA inhibit peptone-stimulated gastric acid secretion and gastrin release, and endogenous secretin released by AA is attributed to this suppression. Thus, the result of this study indicates that intestinal AA regulate gastric secretory function mediated by AA-released endogenous secretin in the intestinal phase.

Amino Acids↗

PubMedDate not supplied

[Sulfated polysaccharides as inhibitors of receptor activity of P-selectin and P-selectin-dependent inflammation].

The inhibitory effects of sulfated polysaccharides-fucoidan and heparin on P-selectin-ligand interaction in vitro and on the ability of fucoidan to inhibit the leukocyte extravasation in rat peritonitis were studied. The lectin activity of P-selectin in vitro was based on its ability to bind lectin-labeled synthetic ligand, Sialyl-Lea/x, conjugated with polyacrylamide (PAA). Fucoidan and heparin inhibited binding of labeled ligand to both purified P-selectin and the activated platelets expressing P-selectin on their surface. The inhibitory effect of fucoidan 100-fold higher than that of heparin. As P-selectin plays an important role at an earlier stage of the inflammation process, the antiinflammatory action of fucoidan on P-selectin-dependent peritonitis in rats was studied. Peritonitis was induced by intraperitoneal injection of the peptone solution and was characterized by an increase in total cell number and neutrophil percentage in rat peritone exudate. Intravenous injection of fucoidan was found to cause a dose- and time-dependent reduction of neutrophil extravasation into inflamed peritoneum. The minimal dose of fucoidan, that was able to produce 96.8 +/- 2.9% inhibition of neutrophil extravasation--if administered within the first 15 min after peptone-B was 0.8 mg per rat. Significant effect of fucoidan injection (about 80% inhibition) was also obtained 1.5 h after the induction of inflammation. Fucoidan administered 2.5 h after peptone had virtually no effect on neutrophil extravasation. The data obtained show that fucoidan blocks the inflammation process at its earlier stages--most probably at the expense of its interaction with P-selectin.

Animals↗

PubMedDate not supplied

Bacillus stearothermophilus sporulation response to different composition media.

To evaluate the effectiveness of 11 commonly used ingredients to improve Bacillus stearothermophilus ATCC 7953 sporulation, with high spore yields in a short period of incubation, 32 composition media were set up by a fractional factorial 2IV11-6 design at two levels: D-glucose (0.018-0.25%), L-glutamic acid (0.040-0.10%), yeast extract (0.050-0.40%), peptone (0.30-0.50%), sodium chloride (0.001-1.0%), magnesium sulfate (0.001-0.20%), ammonium phosphate (0.010-0.035%), potassium phosphate monobasic (0.050-0.25%), calcium chloride (0.001-0.05%), ferrous sulfate (0.0003-0.002%), manganese sulfate (0.001-0.50%). The largest variation on Log10 CFU response took place due to sodium chloride main effect, by changing it from low to high levels. Magnesium sulfate, calcium chloride, and ferrous sulfate were split and exerted no detectable main effect influence on sporulation. Setting up two 16 runs for sodium chloride effect, in each of which the remainder levels were kept constant, other components contribution was studied. At low sodium chloride, best average 7.25 Log10 CFU yielded by fastening yeast extract and peptone at high level, and remainders at low level. Considering high level of sodium chloride, peptone, yeast extract and ammonium phosphate kept at high level and remainders at low level confirmed the best sporulation yield. Adjusted models evidenced a strong influence of joint yeast/peptone effect, associated to ammonium phosphate contributing positively. The reduced incubation period from 15 days to 3-6 days at 62 degrees C was attained for all 32 experimental runs.

Culture Media↗

PubMedDate not supplied

Effect of fortification of concentrated whey on growth of Kluyveromyces sp.

The effect of fortification of concentrated whey with 0.5% inorganic nitrogen viz. NH4Cl, (NH4)2SO4, NaNO3 and urea, organic nitrogen viz. tryptone, tryptose, peptone and yeast extract and 0.1% metal ions viz. K2HPO4, MgSO4 and FeSO4, on growth stimulation of Kluyveromyces marxianus subsp. marxianus NRRL Y-665, NRRL Y-1195, NRRL Y-2415 and Kluyveromyces marxianus subsp. lactis NRRL Y-1193 were studied. Supplementation with 0.5% (NH4)2SO4, peptone, yeast extract or 0.1% K2HPO4 individually increased the biomass production by 8-20%, 17-25%, 13-14% and 14-17%, respectively. Addition of 0.5% each of (NH4)2SO4, peptone, yeast extract and 0.1% K2HPO4 together is recommended to increase the biomass production by 81-98% for commercial production of single cell protein.

Animals↗

PubMed1963

PRODUCTION OF LIPASE BY PSEUDOMONAS FRAGI IN A SYNTHETIC MEDIUM.

Alford, John A. (U.S. Department of Agriculture, Beltsville, Md.) and David A. Pierce. Production of lipase by Pseudomonas fragi in a synthetic medium. J. Bacteriol. 86:24-29. 1963.-The growth and production of lipase by Pseudomonas fragi in 41 dehydrated media were determined. From a chemical analysis of the peptone medium which gave the maximal lipase production, numerous synthetic media were prepared. Good cell growth, but no lipase production, was obtained on a buffered ammonium sulfate-glucose medium. The addition of arginine, lysine, aspartic acid, and glutamic acid to this medium gave lipase production approaching that obtained in the peptone medium. Omission of the glucose had little effect on growth, but no lipase were produced. Sterilization of the glucose with either the amino acids or phosphate buffer had no effect on growth, but sharply reduced lipase production. Gas chromatographic analysis of the fatty acids liberated from lard, corn oil, and coconut oil indicated that medium composition had no effect on enzyme specificity. P. fluorescens produced very little lipase in any of the synthetic media examined.

Adenine↗

PubMed1964

FORMATE-PYRUVATE EXCHANGE REACTION IN STREPTOCOCCUS FAECALIS. I. FACTOR REQUIREMENT FOR INTACT CELLS.

Wood, N. P. (A. & M. College of Texas, College Station), and D. J. O'Kane. Formate-pyruvate exchange reaction in Streptococcus faecalis. I. Factor requirement for whole cells. J. Bacteriol. 87:97-103. 1964.-A factor present in plant and animal sources was found necessary for the incorporation of formate-C(14) into pyruvate by Streptococcus faecalis 10Cl. Yeast extract produced a response linear in the range between 10 and 30 mg/ml of reaction mixture. Soy peptone, beef peptone, and Brain Heart Infusion replaced yeast extract, but various intermediates, cofactors, amino acids, purines, pyrimidines, and peptides did not stimulate the reaction. A lag occurred in the rate of formate incorporation that was not influenced by anaerobic conditions or growth of cells in a medium containing pyruvate and formate. Phosphate or maleate buffer permitted rapid exchange velocities but tris(hydroxymethyl)aminomethane or collidine buffer was inhibitory. Heating yeast extract at 121 C for 15 min in 3 n H(2)SO(4) produced 66% inactivation of the factor(s), whereas treatment with 3 n KOH produced 97% inactivation. The factor(s) was insoluble in butanol, benzene, ethyl acetate, or chloroform. The material adsorbed on Dowex-1 (OH(-)) and Amberlite IR-120 (H(+)) but not on Amberlite IR-4B (OH(-)). The active component(s) was highly polar, nonvolatile, dialyzable, and had amphoteric properties.

Acetates↗

PubMed1964

FATE OF THE MESOSOMES OF BACILLUS MEGATERIUM DURING PROTOPLASTING.

Fitz-James, Philip (University of Western Ontario, London, Canada). Fate of the mesosomes of Bacillus megaterium during protoplasting. J. Bacteriol. 87:1483-1491. 1964.-When cells of Bacillus megaterium growing rapidly in peptone medium are treated with sucrose buffer prior to protoplasting, their membranous organelles or mesosomes are extruded as a collection of vesicles into the wall-membrane interspace. On subsequent protoplast formation with lysozyme digestion, the mesosome remnants become dispersed. If glucose is added to the peptone, a slightly more persistent mesosome can be seen and photographed by phase microscopy during lysozyme digestion, either as a wall-attached granule or as a protoplast tag. In thin section, mesosomes are found as small, variably dispersed aggregates of vesicles and wall-like material. Complete protoplasts are usually free from internal mesosomes but may contain twists or everted pockets of membrane on their periphery. By lysozyme digestion of partially fixed cells, the empty mesosome pockets in the membrane can be demonstrated in rod-shaped protoplasts.

Bacillus megaterium↗

PubMed1988

Effect of treatment medium on induction of aneuploidy by nocodazole in Saccharomyces cerevisiae.

While studying ways to improve responsiveness of Saccharomyces cerevisiae strain D61.M to agents that induce aneuploidy, we noted that nocodazole, which strongly induces aneuploidy when yeast cells are treated in yeast extract-peptone-dextrose (YEPD) medium, had no effect when a synthetic complete (SC) medium was used. Further study revealed that the presence of peptone was necessary for induction. Other aneuploidy-inducing agents, including ethyl acetate, acetone, and methyl benzimidazole-2-yl-carbamate (MBC), were equally active in either medium. Benomyl, which degrades to MBC, was less active in SC than in YEPD medium.

Aneuploidy↗