The recovery of nocardial recombinants from broth cultures

1975 ◽  
Vol 21 (7) ◽  
pp. 1032-1040
Author(s):  
G. H. Brownell ◽  
R. R. Runner
Keyword(s):  
Cell Growth ◽  
Stationary Phase ◽  
Yeast Extract ◽  
Culture Media ◽  
Parental Cell ◽  
Broth Culture ◽  
Low Frequencies ◽  
Growth Requirements ◽  
High Incidence

Broth culture media were examined for their ability to support growth and recombination between compatible strains of Nocardia erythropolis. Nutrient (Nut) and peptone – yeast-extract (PY) broths supported the production of recombinants after 36 h of incubation with a maximum recovery of about 6.0 × 10−1 CFU/ml. Cells mated in trypticase broth (TB) yielded the highest incidence of recombinants (1.0 × 10−2 CFU/ml) in the absence of parental cell growth. From a chemically defined mating broth (CD), supplemented with limited amounts of the parental-growth requirements, recombinant recovery reached about 1.0 × 10−4 after 120 h of incubation. The recombinant class types obtained from Nut- or PY-mated strains were predominantly auxotrophic while TB-mated strains produced stable prototrophs. The high incidence of recombinant types from TB-mated strains was due to growth of selected prototrophic classes. Studies with strains mated in PY broth indicate that the mating event occurs at very low frequencies between older, stationary-phase cells rather than between actively growing, log-phase cells.

scholarly journals GROWTH AND PHAGE PRODUCTION OF LYSOGENIC B. MEGATHERIUM

1951 ◽  
Vol 34 (5) ◽  
pp. 715-735 ◽  
Author(s):  
John H. Northrop
Keyword(s):  
Cell Growth ◽  
Yeast Extract ◽  
Culture Media ◽  
Nucleic Acid Content ◽  
Cell Multiplication ◽  
Yeast Extract Medium ◽  
Tryptose Phosphate Broth ◽  
Phage Production ◽  
Lysogenic Culture ◽  
Short Time

Cell multiplication and phage formation of lysogenic B. megatherium cultures have been determined under various conditions and in various culture media. 1. In general, the more rapid the growth of the culture, the more phage is produced. No conditions or culture media could be found which resulted in phage production without cell growth. 2. Cultures which produce phage grow normally, provided they are shaken. If they are allowed to stand, those which are producing phage undergo lysis. Less phage is produced by these cultures than by the ones which continue to grow. 3. Cells plated from such phage-producing cultures in liquid yeast extract medium grow normally on veal infusion broth agar or tryptose phosphate broth agar, which does not support phage formation, but will not grow on yeast extract agar. 4. Any amino acid except glycine, tyrosine, valine, leucine, and lysine can serve as a nitrogen source. Aspartic acid gives the most rapid cell growth. 5. The ribose nucleic acid content is higher in those cells which produce phage. 6. The organism requires higher concentrations of Mg, Ca, Sr, or Mn to produce phage than for growth. 7. The lysogenic culture can be grown indefinitely in media containing high phosphate concentrations. No phage is produced under these conditions, but the cells produce phage again in a short time after the addition of Mg. The potential ability to produce phage, therefore, is transmitted through cell division. 8. Colonies developed from spores which have been heated to 100°C. for 5 minutes produce phage and hence, infected cells must divide. 9. No phage can be detected after lysis of the cells by lysozyme.

The influence of the initial concentrations of glucose and yeast extract on the ethanolic fermentation by Pachysolen tannophilus

1990 ◽  
Vol 55 (3) ◽  
pp. 854-866 ◽  
Author(s):  
Rodríguez V. Bravo ◽  
Rubio F. Camacho ◽  
Villasclaras S. Sánchez ◽  
Vico M. Castro
Keyword(s):  
Cell Growth ◽  
Ethanol Production ◽  
Yeast Extract ◽  
Culture Medium ◽  
Ethanolic Fermentation ◽  
Pachysolen Tannophilus ◽  
Significant Component ◽  
Batch Cultures

The ethanolic fermentation in batch cultures of Pachysolen tannophilus was studied experimentally varying the initial concentrations of two of the components in the culture medium: glucose between 0 and 200 g l-1 and yeast extract between 0 and 8 g l-1. The yeast extract appears to be a significant component both in cell growth and for ethanol production.

scholarly journals The rye Mutants Identify a Role for Ssn/Srb Proteins of the RNA Polymerase II Holoenzyme During Stationary Phase Entry in Saccharomyces cerevisiae

Genetics ◽  
2001 ◽  
Vol 157 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Ya-Wen Chang ◽  
Susie C Howard ◽  
Yelena V Budovskaya ◽  
Jasper Rine ◽  
Paul K Herman
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Growth ◽  
Rna Polymerase ◽  
Stationary Phase ◽  
Yeast Cell ◽  
Rna Polymerase Ii ◽  
Transcriptional Response ◽  
Nutrient Deprivation ◽  
Ras Signaling ◽  
Rna Polymerase Ii Holoenzyme

Abstract Saccharomyces cerevisiae cells enter into a distinct resting state, known as stationary phase, in response to specific types of nutrient deprivation. We have identified a collection of mutants that exhibited a defective transcriptional response to nutrient limitation and failed to enter into a normal stationary phase. These rye mutants were isolated on the basis of defects in the regulation of YGP1 expression. In wild-type cells, YGP1 levels increased during the growth arrest caused by nutrient deprivation or inactivation of the Ras signaling pathway. In contrast, the levels of YGP1 and related genes were significantly elevated in the rye mutants during log phase growth. The rye defects were not specific to this YGP1 response as these mutants also exhibited multiple defects in stationary phase properties, including an inability to survive periods of prolonged starvation. These data indicated that the RYE genes might encode important regulators of yeast cell growth. Interestingly, three of the RYE genes encoded the Ssn/Srb proteins, Srb9p, Srb10p, and Srb11p, which are associated with the RNA polymerase II holoenzyme. Thus, the RNA polymerase II holoenzyme may be a target of the signaling pathways responsible for coordinating yeast cell growth with nutrient availability.

Roquefortine C Occurrence in Blue Cheese

2001 ◽  
Vol 64 (2) ◽  
pp. 246-251 ◽  
Author(s):  
CARLO FINOLI ◽  
ANGELA VECCHIO ◽  
ANTONIETTA GALLI ◽  
IVAN DRAGONI
Keyword(s):  
Yeast Extract ◽  
Culture Media ◽  
Penicillium Roqueforti ◽  
Blue Cheese ◽  
Penicillium Crustosum ◽  
Sucrose Medium ◽  
Low Toxicity ◽  
Yeast Extract Sucrose ◽  
Roquefortine C

Several strains of Penicillium are used for the production of mold-ripened cheeses, and some of them are able to produce mycotoxins. The aims of the research were the determination of roquefortine C and PR toxin in domestic and imported blue cheeses, the identification of the penicillia used as starter, and the investigation of their capacity for producing toxins in culture media. Roquefortine C was always found in the cheeses at levels ranging from 0.05 to 1.47 mg/kg, whereas the PR toxin was never found. The identification of the fungal strains present in the domestic cheeses included Penicillium glabrum, Penicillium roqueforti, and Penicillium cyclopium in the Gorgonzola “dolce” and Penicillium roqueforti in the Gorgonzola “naturale”; in one case, the presence of Penicillium crustosum was observed. The strains isolated from the foreign cheeses belonged to P. roqueforti. The strains were able to produce between 0.18 and 8.44 mg/liter of roquefortine in yeast extract sucrose medium and between 0.06 and 3.08 mg/liter and less than 0.05 mg/liter when inoculated in milk at 20°C for 14 days and 4°C for 24 days, respectively. Linear relations between production of roquefortine in culture media and cheeses did not emerge. PR toxin ranged from less than 0.05 to 60.30 mg/liter in yeast extract sucrose medium and was produced in milk at 20°C from only one strain. The low levels and the relatively low toxicity of roquefortine make the consumption of blue cheese safe for the consumer.

scholarly journals Bacterial Cellulose as a Substrate for Microbial Cell Culture

2014 ◽  
Vol 80 (6) ◽  
pp. 1926-1932 ◽  
Author(s):  
Na Yin ◽  
Thiago M. A. Santos ◽  
George K. Auer ◽  
John A. Crooks ◽  
Piercen M. Oliver ◽  
...  
Keyword(s):  
Cell Culture ◽  
Cell Growth ◽  
Physicochemical Properties ◽  
Stationary Phase ◽  
Bacterial Cellulose ◽  
Growth Rates ◽  
Bacterial Cell ◽  
Acetobacter Xylinum ◽  
Primary Factor ◽  
Nutrient Diffusion

ABSTRACTBacterial cellulose (BC) has a range of structural and physicochemical properties that make it a particularly useful material for the culture of bacteria. We studied the growth of 14 genera of bacteria on BC substrates produced byAcetobacter xylinumand compared the results to growth on the commercially available biopolymers agar, gellan, and xanthan. We demonstrate that BC produces rates of bacterial cell growth that typically exceed those on the commercial biopolymers and yields cultures with higher titers of cells at stationary phase. The morphology of the cells did not change during growth on BC. The rates of nutrient diffusion in BC being higher than those in other biopolymers is likely a primary factor that leads to higher growth rates. Collectively, our results suggest that the use of BC may open new avenues in microbiology by facilitating bacterial cell culture and isolation.

scholarly journals Fetal Bovine Serum-Derived Extracellular Vesicles Persist within Vesicle-Depleted Culture Media

2018 ◽  
Vol 19 (11) ◽  
pp. 3538 ◽  
Author(s):  
Brandon Lehrich ◽  
Yaxuan Liang ◽  
Pooya Khosravi ◽  
Howard Federoff ◽  
Massimo Fiandaca
Keyword(s):  
Cell Growth ◽  
Extracellular Vesicles ◽  
Bovine Serum ◽  
Culture Media ◽  
Fetal Bovine Serum ◽  
Cellular Growth ◽  
Primary Astrocyte ◽  
Fetal Bovine ◽  
Cell Growth And Viability

It is known that culture media (CM) promotes cellular growth, adhesion, and protects explanted primary brain cells from in vitro stresses. The fetal bovine serum (FBS) supplement used in most CM, however, contains significant quantities of extracellular vesicles (EVs) that confound quantitative and qualitative analyses from the EVs produced by the cultured cells. We quantitatively tested the ability of common FBS EV-depletion protocols to remove exogenous EVs from FBS-supplemented CM and evaluated the influence such methods have on primary astrocyte culture growth and viability. We assessed two methodologies utilized for FBS EV removal prior to adding to CM: (1) an 18-h ultracentrifugation (UC); and (2) a commercial EV-depleted FBS (Exo-FBS™). Our analysis demonstrated that Exo-FBS™ CM provided the largest depletion (75%) of total FBS EVs, while still providing 6.92 × 109 ± 1.39 × 108 EVs/mL. In addition, both UC and Exo-FBS™ CM resulted in poor primary astrocyte cell growth and viability in culture. The two common FBS EV-depletion methods investigated, therefore, not only contaminate in vitro primary cell-derived EV analyses, but also provide a suboptimal environment for primary astrocyte cell growth and viability. It appears likely that future CM optimization, using a serum-free alternative, might be required to advance analyses of cell-specific EVs isolated in vitro.

scholarly journals l-Pyroglutamate Spontaneously Formed from l-Glutamate Inhibits Growth of the Hyperthermophilic Archaeon Sulfolobus solfataricus

2001 ◽  
Vol 67 (8) ◽  
pp. 3650-3654 ◽  
Author(s):  
Chan B. Park ◽  
Sun Bok Lee ◽  
Dewey D. Y. Ryu
Keyword(s):  
Cell Growth ◽  
Growth Inhibition ◽  
Yeast Extract ◽  
Formation Rate ◽  
Sulfolobus Solfataricus ◽  
Methionine Sulfoxide ◽  
Inhibitory Effect ◽  
Culture Conditions ◽  
Culture Broth ◽  
Cell Growth Inhibition

ABSTRACT Identification of physiological and environmental factors that limit efficient growth of hyperthermophiles is important for practical application of these organisms to the production of useful enzymes or metabolites. During fed-batch cultivation of Sulfolobus solfataricus in medium containing l-glutamate, we observed formation of l-pyroglutamic acid (PGA). PGA formed spontaneously from l-glutamate under culture conditions (78°C and pH 3.0), and the PGA formation rate was much higher at an acidic or alkaline pH than at neutral pH. It was also found that PGA is a potent inhibitor of S. solfataricus growth. The cell growth rate was reduced by one-half by the presence of 5.1 mM PGA, and no growth was observed in the presence of 15.5 mM PGA. On the other hand, the inhibitory effect of PGA on cell growth was alleviated by addition of l-glutamate or l-aspartate to the medium. PGA was also produced from the l-glutamate in yeast extract; the PGA content increased to 8.5% (wt/wt) after 80 h of incubation of a yeast extract solution at 78°C and pH 3.0. In medium supplemented with yeast extract, cell growth was optimal in the presence of 3.0 g of yeast extract per liter, and higher yeast extract concentrations resulted in reduced cell yields. The extents of cell growth inhibition at yeast extract concentrations above the optimal concentration were correlated with the PGA concentration in the culture broth. Although other structural analogues ofl-glutamate, such as l-methionine sulfoxide, glutaric acid, succinic acid, and l-glutamic acid γ-methyl ester, also inhibited the growth of S. solfataricus, the greatest cell growth inhibition was observed with PGA. We also observed that unlike other glutamate analogues,N-acetyl-l-glutamate enhanced the growth of S. solfataricus. This compound was stable under cell culture conditions, and replacement of l-glutamate with N-acetyl-l-glutamate in the medium resulted in increased cell density.

scholarly journals Oxygen and Glucose Levels in Cell Culture Media Determine Resveratrol’s Effects on Growth, Hydrogen Peroxide Production, and Mitochondrial Dynamics

Antioxidants ◽  
2018 ◽  
Vol 7 (11) ◽  
pp. 157 ◽  
Author(s):  
Joao Fonseca ◽  
Fereshteh Moradi ◽  
Andrew Valente ◽  
Jeffrey Stuart
Keyword(s):  
Hydrogen Peroxide ◽  
Cell Culture ◽  
Cell Growth ◽  
Cultured Cells ◽  
Culture Media ◽  
Mitochondrial Dynamics ◽  
Mitochondrial Network ◽  
Hydrogen Peroxide Production ◽  
Network Characteristics ◽  
Glucose Levels

Resveratrol is a plant-derived polyphenol that has been widely studied for its putative health promoting effects. Many of those studies have been conducted in cell culture, in supra-physiological levels of oxygen and glucose. Resveratrol interacts with reactive oxygen species (ROS) as an antioxidant or pro-oxidant. Resveratrol affects the expression and activities of ROS-producing enzymes and organelles. It is therefore important to consider how cell culture conditions might determine the effects of resveratrol on cultured cells. We determined the effects of resveratrol on cell growth, hydrogen peroxide production, and mitochondrial network characteristics in C2C12 mouse myoblasts and PC3 human prostate cancer cells under conditions of physiological (5%) and supra-physiological (18%) oxygen, and normo- (5 mM) and hyper-glycemia (25 mM). Interestingly, most effects of resveratrol on the parameters measured here were dependent upon prevailing oxygen and glucose levels during the experiment. Many of the effects of resveratrol on cell growth, hydrogen peroxide production, and mitochondrial network characteristics that were seen in 25 mM glucose and/or 18% oxygen were absent under the physiologically relevant conditions of 5 mM glucose with 5% oxygen. These findings emphasize the importance of using physiologically meaningful starting conditions for cell-culture experiments with resveratrol and indeed any manipulation affecting ROS metabolism and mitochondria.

Sign in / Sign up

Export Citation Format

Share Document