scholarly journals The glycosulphatase of Trichoderma viride

1968 ◽  
Vol 108 (3) ◽  
pp. 393-399 ◽  
Author(s):  
A G Lloyd ◽  
P J Large ◽  
M Davies ◽  
A H Olavesen ◽  
K S Dodgson
Keyword(s):  
Culture Medium ◽  
Enzyme System ◽  
Trichoderma Viride ◽  
Defined Medium ◽  
Potassium Sulphate ◽  
Experimental Conditions ◽  
Lag Period

The growth of the mould Trichoderma viride on a defined medium containing either potassium d-glucose 6-O-sulphate or potassium d-galactose 6-O-sulphate as sole sources of both carbon and sulphur is marked by the production of an enzyme system capable of liberating inorganic SO42− ions from either of the sulphate esters. The enzyme is not produced when the organism is grown with glucose (or galactose) and potassium sulphate or with glucose and methionine as sole sources of carbon and sulphur. Experimental conditions are described whereby inorganic SO42− ions liberated from potassium glucose 6-O-sulphate by the growing mould appear in the culture medium after a constant lag period of 21–24hr. The enzyme has been shown to be a simple glycosulphatase that is active towards the 6-O-sulphate esters of d-glucose and d-galactose but not towards potassium glucose 3-O-sulphate. The properties of the crude glycosulphatase show the enzyme to be appreciably different from analogous molluscan enzymes that can degrade monosaccharide sulphate esters.

Optimisation de la croissance et de la sporulation de Conidiobolus obscurus en milieu défini

1985 ◽  
Vol 63 (1) ◽  
pp. 68-85 ◽  
Author(s):  
J. P. Latgé ◽  
J. J. Sanglier
Keyword(s):  
Amino Acids ◽  
Culture Medium ◽  
Pantothenic Acid ◽  
Defined Medium ◽  
Culture Conditions ◽  
Complete Darkness ◽  
Experimental Conditions ◽  
Nutritional Factors ◽  
Factors Influencing ◽  
Composite Designs

Physical and nutritional factors influencing the growth and sporulation of Conidiobolus obscurus (Hall et Dunn) Remaudière et Keller were studied using simple and fragmented factorial designs and centered composite designs. Culture conditions allowing maximum sporulation were a temperature of 20 °C, complete darkness, and a near neutral pH of around 6.5. Under our experimental conditions, dextrose influenced neither the growth nor the sporulation of C. obscurus. The cations stimulating the formation of azygospores were magnesium and to a lesser extent zinc and manganese. Sulphur must be added to the medium in a reduced or oxydized form. Phosphates must be present in the culture medium, but at a concentration less than 30 mM/L. Vitamins stimulating sporulation were thiamine, biotin, and folic acid while pantothenic acid favoured growth. Among the 20 amino acids tested, proline, leucine, methionine, glutamic and aspartic acids, glutamine, asparagine, histidine, phenylalanine, lysine, and arginine were the most favourable for growth and sporulation of C. obscurus. Growth and sporulation in the optimized defined medium containing 11 amino acids, four vitamins, four salts, and dextrose were comparable to the best results obtained in a nondefined medium composed of dextrose and yeast extract.

scholarly journals Sulphur utilization during growth of Pseudomonas fluorescens on potassium d-glucose 6-O-sulphate

1971 ◽  
Vol 121 (3) ◽  
pp. 521-528 ◽  
Author(s):  
J. W. Fitzgerald ◽  
K. S. Dodgson
Keyword(s):  
Pseudomonas Fluorescens ◽  
Culture Medium ◽  
Enzyme System ◽  
Culture Fluid ◽  
Major Metabolite ◽  
Potassium Sulphate ◽  
Sulphur Source ◽  
Sulphate Sulphur

Pseudomonas fluorescens N.C.I.B. 8248 was adapted to grow on potassium d-glucose 6-O-sulphate as the sole carbon and sulphur source. Adapted bacteria grew optimally at 37°C on 1.6% (w/v) sulphate ester and growth coincided with the disappearance of the ester from the culture medium at a rate of 2.4mg/h per ml. Three sulphated compounds were detected in the culture fluid at the termination of growth. One of these was present in traces only and has not been identified. The second was present in somewhat greater amounts and was identified as the 6-O-sulphate ester of d-gluconate, and the major metabolite was identified as d-glycerate 3-O-sulphate. Sulphur utilization by the organism was not associated with the appearance of a glycosulphatase enzyme in the cells. However, a novel enzyme system (or systems) was present that liberated inorganic 35SO42− ions from dipotassium d-gluconate 6[35S]-O-sulphate and from dipotassium dl-glycerate 3[35S]-O-sulphate. Activity towards the latter substrate could not be detected when the adapted or parent Pseudomonas strain was cultured on d-glucose and potassium sulphate as respective carbon and sulphur sources. Some properties of the enzyme acting on the glycerate ester are recorded.

scholarly journals Transcriptional Profiling of Porcine Blastocysts Produced In Vitro in a Chemically Defined Culture Medium

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1414
Author(s):  
Josep M. Cambra ◽  
Emilio A. Martinez ◽  
Heriberto Rodriguez-Martinez ◽  
Maria A. Gil ◽  
Cristina Cuello
Keyword(s):  
Culture Medium ◽  
Embryo Quality ◽  
Transcriptional Profiling ◽  
Defined Medium ◽  
Platelet Factor ◽  
Defined Media ◽  
Defined Culture ◽  
The Impact

The development of chemically defined media is a growing trend in in vitro embryo production (IVP). Recently, traditional undefined culture medium with bovine serum albumin (BSA) has been successfully replaced by a chemically defined medium using substances with embryotrophic properties such as platelet factor 4 (PF4). Although the use of this medium sustains IVP, the impact of defined media on the embryonic transcriptome has not been fully elucidated. This study analyzed the transcriptome of porcine IVP blastocysts, cultured in defined (PF4 group) and undefined media (BSA group) by microarrays. In vivo-derived blastocysts (IVV group) were used as a standard of maximum embryo quality. The results showed no differentially expressed genes (DEG) between the PF4 and BSA groups. However, a total of 2780 and 2577 DEGs were detected when comparing the PF4 or the BSA group with the IVV group, respectively. Most of these genes were common in both in vitro groups (2132) and present in some enriched pathways, such as cell cycle, lysosome and/or metabolic pathways. These results show that IVP conditions strongly affect embryo transcriptome and that the defined culture medium with PF4 is a guaranteed replacement for traditional culture with BSA.

Development of embryonic rat eyes in organ culture

Development ◽  
1968 ◽  
Vol 19 (3) ◽  
pp. 407-414
Author(s):  
R. Christy Armstrong ◽  
Joel J. Elias
Keyword(s):  
Organ Culture ◽  
Culture Medium ◽  
Folic Acid Deficiency ◽  
Experimental Conditions ◽  
Acid Deficiency ◽  
Series Of Experiments ◽  
Development In Vitro ◽  
Ocular System

Abnormalities of the ocular system which appear in organ culture in Waymouth's medium with freshly added glutamine (Armstrong & Elias, 1968) resemble those caused by transitory pteryolglutamic acid (PGA or folic acid) deficiency in vivo (Armstrong & Monie, 1966). The configurations of such malformations as lens herniations, retinal diverticula, and rosette-like formations of the retina are remarkably similar in both cases. The experiments reported in this paper were undertaken in an effort to understand the mechanisms involved in the production of similar abnormalities by two very different experimental conditions: the addition of glutamine in vitro and the transitory deficiency of PGA in vivo. One series of experiments involved the effects of manipulation of the PGA and glutamine content of the culture medium on eye development in vitro. Parallel studies on PGA-deficiency in vivo were undertaken in conjunction with organ-culture experiments in order to compare the effects on abnormal eye morphogenesis.

scholarly journals Dynamics of leukotriene C production by macrophages.

1980 ◽  
Vol 152 (5) ◽  
pp. 1236-1247 ◽  
Author(s):  
C A Rouzer ◽  
W A Scott ◽  
A L Hamill ◽  
Z A Cohn
Keyword(s):  
Time Course ◽  
Culture Medium ◽  
Peritoneal Macrophages ◽  
Experimental Conditions ◽  
Silicic Acid Chromatography ◽  
Pg Release ◽  
Antigen Antibody ◽  
Mouse Peritoneal Macrophages ◽  
Hydroxyeicosatetraenoic Acids

A method for the radiochemical assay of LTC production by mouse peritoneal macrophages in vitro is presented. The method involves labeling macrophages in culture with [5,6,8,9,11,12,14,15-3H]20:4 followed by stimulation of arachidonic acid (20:4) release under the experimental conditions desired. Radiolabeled leukotriene C (LTC) is recovered from the culture medium by extraction and silicic acid chromatography in 40% yield with full retention of biological activity. Because this LTC is radiochemically pure, the quantity of LTC release may be estimated from the amount of radioactivity in the sample. Use of the radioassay to study parameters affecting LTC synthesis by macrophages indicated that the time course of LTC synthesis and its relationship to the dose of a phagocytic stimulus (zymosan) were very similar to those of prostaglandin (PG) release. LTC release was also similar to that of PG in that lower levels of both metabolites were produced by Corynebacterium parvum-elicited macrophages than by resident cells. Finally, LTC release was stimulated in response to a challenge with antigen-antibody complexes, but lower maximal levels were attained than those with zymosan. The data presented here are consistent with the hypothesis that challenge of macrophages with a phagocytic stimulus leads to the release of 20:4 by an inducible phospholipase. Cyclooxygenase and lipoxygenase then compete for the released 20:4, leading to the production of PG, hydroxyeicosatetraenoic acids, and LTC.

Influence of Irradiance on H+ Efflux and Cl- Influx in Chara corallina: An Investigation Aimed at Testing Two Cl- Transport Models

1976 ◽  
Vol 3 (4) ◽  
pp. 443
Author(s):  
W.J Lucas ◽  
F.A Smith
Keyword(s):  
Transport System ◽  
Energy Supply ◽  
Chara Corallina ◽  
Maximum Activity ◽  
Present Form ◽  
Significant Modification ◽  
Transport Models ◽  
Experimental Conditions ◽  
Cl Transport ◽  
Lag Period

Parallel studies on the influence of irradiance on net H+ efflux and *36Cl- uptake were conducted on C. corallina. Following the dark-to-light transition, a lag period of 8-15 min was observed before net H+ efflux activity could be discerned experimentally. Decreasing the irradiance did not significantly lengthen this lag period. Studies on *36Cl- uptake revealed that a lag period of 40-60 min was required before the Cl- transport system attained maximum activity, governed by the prevailing experimental conditions. These results are discussed in relation to the Cl- transport hypotheses proposed by Spear et al. and by Smith. It would seem that the hypothesis of Spear et al., in its present form, is invalid for Chara corallina. The results were inconclusive in terms of support (or otherwise) for a Cl-/OH- antiporter. However, the Cl-/OH- antiporter hypothesis originally proposed by Smith will require significant modification, especially in terms of the energy supply.

Detection Method for Histamine-Producing, Dairy-Related Bacteria using Diamine Oxidase and Leucocrystal Violet

1989 ◽  
Vol 52 (2) ◽  
pp. 105-108 ◽  
Author(s):  
SUSAN S. SUMNER ◽  
STEVE L. TAYLOR
Keyword(s):  
Hydrogen Peroxide ◽  
Liquid Culture ◽  
Diamine Oxidase ◽  
Culture Medium ◽  
Detection Method ◽  
Enzyme System ◽  
Color Formation ◽  
Liquid Culture Medium ◽  
Leucocrystal Violet ◽  
Purple Color

A detection method for histamine-producing, dairy-related bacteria was developed that involves a two-step sequential enzyme system. First, isolated bacteria are incubated in MRS broth or trypticase soy broth fortified with histidine. The histamine formed during this incubation period is reacted with diamine oxidase, which catalyzes the oxidation of histamine to form imidazole acetaldehyde, ammonia, and hydrogen peroxide. The hydrogen peroxide is then detected by the formation of crystal violet from the leuco base in the presence of horseradish peroxidase. Liquid culture medium containing bacteria that produce greater than 1200 nmole histamine per ml will develop a positive purple color. Cultures containing bacteria that produce little or no histamine will not develop a purple color. Other amines often found in cheese, such as tyramine, cadaverine, or putrescine, will not interfere with the color formation.

Feeding of Boophilus microplus larvae on a partially defined medium through thin slices of cattle skin

Parasitology ◽  
1975 ◽  
Vol 70 (2) ◽  
pp. 243-254 ◽  
Author(s):  
D. H. Kemp ◽  
D. Koudstaal ◽  
J. A. Roberts ◽  
J. D. Kerr
Keyword(s):  
Bovine Serum ◽  
Freeze Drying ◽  
Culture Medium ◽  
Culture Method ◽  
Defined Medium ◽  
Boophilus Microplus ◽  
Cattle Tick ◽  
Haemaphysalis Longicornis ◽  
Freeze Dried ◽  
Thin Slices

Larvae of the cattle tick Boophilus microplus will attach to thin (0·3–0·5 mm) slices of cattle skin and engorge on a partially denned medium at 35 °C. Forty-seven to 83% of the larvae had engorged by 8 days, and 51–71% of these moulted to nymphs. Tissue culture medium alone allowed little growth unless supplemented with dialysed, freeze dried bovine serum (7%, w/v). This medium could be further defined by substituting purified bovine serum albumin (Cohn fraction V) for the dialysed bovine serum. In one experiment, nymphs of Haemaphysalis longicornis engorged and later moulted to adults. Skin slices were used fresh or after freeze-drying and storing at − 25 °C. The possible uses of the culture method are discussed.

Electrochemical Study of Mannitol Oxidation at Nickel Oxide Electrode

2003 ◽  
Vol 68 (9) ◽  
pp. 1636-1646
Author(s):  
Domenica Tonelli ◽  
Barbara Ballarin ◽  
Mario Berrettoni ◽  
Marcello Trevisani
Keyword(s):  
Nickel Oxide ◽  
Culture Medium ◽  
Electrochemical Reaction ◽  
Oxide Electrode ◽  
Experimental Conditions ◽  
Liquid Culture Medium ◽  
Viable Cells ◽  
Nickel Oxide Electrode ◽  
Kinetics Of ◽  
Overall Kinetics

The electrocatalytic oxidation of mannitol at a nickel oxide electrode was investigated. The experimental conditions for determining mannitol concentrations have been optimised taking into account the involved electrochemistry. Unlike what previously reported in the literature, our findings lead to the conclusion that both the electrochemical reaction involving the Ni(II)/Ni(III) couple and the chemical reaction between mannitol and Ni(III) are effective in determining the overall kinetics of the electrocatalytic process. The calibration line for mannitol was linear up to 20.0 mmol l-1. Mannitol determination with the nickel oxide electrode was performed in a liquid culture medium selective for Staphylococcus aureus in order to make an indirect calibration of bacterial viable cells, but the results were not satisfactory.

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