Sporulation of Streptomyces antibioticus ETHZ 7451 in submerged culture

1992 ◽  
Vol 38 (8) ◽  
pp. 769-773 ◽  
Author(s):  
Isabel S. Novella ◽  
Covadonga Barbés ◽  
Jesús Sánchez
Keyword(s):  
Growth Rates ◽  
Submerged Culture ◽  
Carbon Sources ◽  
High Growth ◽  
Nitrogen Sources ◽  
Lower Growth ◽  
Streptomyces Antibioticus ◽  
Sporulation Efficiency ◽  
Repressive Effect ◽  
Casamino Acids

Streptomyces antibioticus ETHZ 7451 formed spores in cultures grown in a liquid medium from either a spore or a mycelium inoculum. The spores formed were similar to those formed on surface-grown cultures, except for reduced heat resistance. Both types of spores were sensitive to lysozyme, which is unusual for Streptomyces spores. Glucose and other carbon sources, which promoted different growth rates, did not affect sporulation efficiency. Nitrogen sources, such as casamino acids, that allowed high growth rates suppressed the sporulation. A remarkable repression was also observed in media with some nitrogen sources that promoted noticeably lower growth rates. In permissive media, with nitrogen sources that permitted relatively high growth rates, sporulation was conditioned to the consumption of ammonium in the medium, but not to that of other nitrogen sources, such as asparagine. Phosphate did not show a repressive effect on sporulation in the assayed conditions. Key words: Streptomyces antibioticus, sporulation.

Biomass Reduction and Mineralization Increase Due to the Ciliate Tetrahymena pyriformis Grazing on the Bacterium Pseudomonas fluorescens

1994 ◽  
Vol 29 (7) ◽  
pp. 119-128 ◽  
Author(s):  
C. H. Ratsak ◽  
B. W. Kooi ◽  
H. W. van Verseveld
Keyword(s):  
Growth Rates ◽  
Growth Parameters ◽  
Waste Water Treatment ◽  
High Growth ◽  
Tetrahymena Pyriformis ◽  
Lower Growth ◽  
Purification Efficiency ◽  
High Purification ◽  
Biomass Reduction ◽  
Sludge Production

The currently high sludge production and increasing processing costs call for waste-water treatment plants with high purification efficiency and low biomass production. We studied the latter issue through two-stage chemostat cascades to assess the overall biomass reduction due to ciliate grazing. The bacteria were cultured in the first chemostat whereas the ciliates, grazing on the bacteria from the first chemostat, were cultured in the second chemostat. Mathematical modelling was used to describe the bacteria/ciliate dynamics and some of the growth parameters were fitted. In the second chemostat 22-44% of the carbon originating from the first chemostat was mineralized to CO2. An extra biomass reduction of 12-43% was possible due to grazing by the ciliates. At lower growth rates of the ciliates the extra biomass reduction was higher than at high growth rates. This finding is auspicious, suggesting that predator organisms indeed can reduce sludge production.

scholarly journals Characterization of a rare species of Neurospora isolated from a river water sample in China

2015 ◽  
Vol 67 (2) ◽  
pp. 685-693 ◽  
Author(s):  
Xia Yang ◽  
Siliang Huang ◽  
Yubian Zhang ◽  
Xiaoqiang Zhang
Keyword(s):  
Water Sample ◽  
River Water ◽  
Growth Rates ◽  
Rare Species ◽  
Vegetative Growth ◽  
Carbon Sources ◽  
Morphological Characteristics ◽  
Nitrogen Sources ◽  
Fungal Species ◽  
River Water Sample

A fungal isolate (ZZS4408) was obtained from a river water sample in Henan, China, and identified as a member of Neurospora brevispora, a rare species of Neurospora based on its morphological characteristics and ribosomal DNA internal transcribed spacer (rDNA-ITS) sequence. The temperatures suitable for growth of the isolate were 28-37?C with 31?C as the optimum. The growth rates of hyphal tips were 19.1-42.5 (av. 31.9) ?m min-1 at 32?C. The pH suitable for vegetative growth ranged from 5 to 7, with pH 5.5 as the optimum. The heterodisaccharides (sucrose and lactose) and D-alanine were found to be most favorable for vegetative growth of the isolate, as carbon and nitrogen sources, respectively. The vegetative growth of the isolate was more significantly influenced by nitrogen sources compared to carbon sources. N. brevispora could be considered a desirable fungal species for morphodifferentiation studies due to its rapid growth rates under favorable conditions.

Nutritional and environmental factors affecting growth and sporulation of Sporidesmium sclerotivorum

1981 ◽  
Vol 27 (7) ◽  
pp. 685-691 ◽  
Author(s):  
E. A. Barnett ◽  
W. A. Ayers
Keyword(s):  
Nitrogen Source ◽  
Agar Medium ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
Mineral Salts ◽  
Factors Affecting ◽  
Carbon And Nitrogen ◽  
Naoh Solution ◽  
Casamino Acids ◽  
Nutritional Studies

Three of five isolates of Sporidesmium sclerotivorum, a mycoparasite of Sclerotinia spp., grew well on an agar medium containing mineral salts, glucose, thiamine, and glutamine or Casamino acids as the nitrogen source. The nitrogen requirement for two of the isolates was satisfied by NH4Cl, Casamino acids, or glutamine. Glutamine was the best single nitrogen source. Only one isolate, CS-1, was used in further nutritional studies. The optimum concentration of glutamine for growth was 5 g/L. Glucose, mannose, mannitol, and cellobiose were excellent carbon sources. A glucose concentration of 20 g/L was optimum. Mannitol supported greater growth than glucose with Casamino acids as the nitrogen source but glucose was the superior carbon source with glutamine as the nitrogen source. Greatest growth was achieved with a combination of these carbon and nitrogen sources. Sporidesmium sclerotivorum, isolate CS-1, required thiamine for growth and sporulation. Biotin stimulated growth. The fungus developed maximally within the range of pH 5.0–5.5 and growth was greatly reduced at a pH below 4.0 or above 6.0. Control of acidity by the periodic addition of NaOH solution permitted substantially increased growth. The optimum temperature for growth was 22.5–25.0 °C but production of macroconidia was greatest at 15–20 °C.

scholarly journals No selection for greater size in an introduced grass invading semiarid grassland

Botany ◽  
2016 ◽  
Vol 94 (10) ◽  
pp. 957-966 ◽  
Author(s):  
Malin J. Hansen ◽  
Scott D. Wilson
Keyword(s):  
Great Plains ◽  
Artificial Selection ◽  
Growth Rates ◽  
Native Species ◽  
High Growth ◽  
Tiller Number ◽  
Lower Growth ◽  
Semiarid Grassland ◽  
Growing Seasons ◽  
Common Gardens

Exotic species are often planted for restoration or to enhance production. Populations that expand from plantings may undergo selection in directions that differ from those produced by artificial selection prior to planting. Here, we test whether a highly productive grass, Agropyron cristatum (L.) Gaertn., introduced to the semiarid Great Plains of North America, evolves during invasion from seeded fields into native grassland. We grew individuals of A. cristatum from six seeded populations and 12 invading populations in 12 common gardens separated by 0.5–12 km for two growing seasons. Contrary to expectations, individuals from invading populations did not have significantly greater tiller number or growth (increase in tiller number) than did individuals from seeded populations, suggesting that they have not undergone evolution towards increased invasion ability through increased size or growth. Instead, there was a general trend for individuals from invading populations to have lower growth rates and fewer tillers when grown without neighbours. Large size or high growth rates arising from artificial selection prior to introduction may be disadvantageous to populations invading semiarid grassland on dry, nutrient-poor soils. In this case, evolution may have resulted in convergence between the relatively large planted species and the smaller native species.

Sporulation of Gibberella zeae. III. Carbon and nitrogen nutrition on growth and macroconidium production

1970 ◽  
Vol 48 (7) ◽  
pp. 1335-1337 ◽  
Author(s):  
W. G. Bonn ◽  
R. A. Cappellini
Keyword(s):  
Organic Acid ◽  
Aspartic Acid ◽  
Growth Rates ◽  
Nitrogen Nutrition ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
Gibberella Zeae ◽  
Good Growth ◽  
Carbon And Nitrogen ◽  
The Media

Differences in growth rates and macroconidium production occurred between shake and standing cultures of a non-sporulating strain of Gibberella zeae (Schw.) Petch. Good growth occurred on all carbon sources except lactose, acetate, citrate, and α-ketoglutarate, and on all nitrogen sources except NaNO2. The pH of the media changed during growth, dropping to about 3 with the sugar and rising to about 9 with the organic acid and nitrogen sources. Little or no sporulation was observed in standing cultures. Sugars appeared to inhibit, and tricarboxylic cycle acids, aspartic acid, and phenylalanine stimulated sporulation.

scholarly journals Growth Rate-Dependent Control in Enterococcus faecalis: Effects on the Transcriptome and Proteome, and Strong Regulation of Lactate Dehydrogenase

2011 ◽  
Vol 78 (1) ◽  
pp. 170-176 ◽  
Author(s):  
Ibrahim Mehmeti ◽  
Ellen M. Faergestad ◽  
Martijn Bekker ◽  
Lars Snipen ◽  
Ingolf F. Nes ◽  
...  
Keyword(s):  
Growth Rate ◽  
Lactate Dehydrogenase ◽  
Enterococcus Faecalis ◽  
Growth Rates ◽  
Posttranscriptional Regulation ◽  
High Growth ◽  
Regulation Of Expression ◽  
Lower Growth ◽  
Content Type ◽  
Rate Dependent

ABSTRACTEnterococcus faecalisV583 was grown in a glucose-limited chemostat at three different growth rates (0.05, 0.15, and 0.4 h−1). The fermentation pattern changed with growth rate, from a mostly homolactic profile at a high growth rate to a fermentation dominated by formate, acetate, and ethanol production at a low growth rate. A number of amino acids were consumed at the lower growth rates but not by fast-growing cells. The change in metabolic profile was caused mainly by decreased flux through lactate dehydrogenase. The transcription ofldh-1, encoding the principal lactate dehydrogenase, showed very strong growth rate dependence and differed by three orders of magnitude between the highest and the lowest growth rates. Despite the increase inldh-1 transcript, the content of the Ldh-1 protein was the same under all conditions. Using microarrays and quantitative PCR, the levels of 227 gene transcripts were found to be affected by the growth rate, and 56 differentially expressed proteins were found by proteomic analyses. Few genes or proteins showed a growth rate-dependent increase or decrease in expression across the whole range of conditions, and many showed a maximum or minimum at the middle growth rate (i.e., 0.15 h−1). For many gene products, a discrepancy between transcriptomic and proteomic data were seen, indicating posttranscriptional regulation of expression.

The Influence of Hydrogen Dilution and Substrate Temperature in Hot-Wire Deposition of Amorphous and Microcrystalline Silicon With Filament Temperatures Between 1900 And 2500 °C

1996 ◽  
Vol 420 ◽  
Author(s):  
J. P. Conde ◽  
P. Brogueira ◽  
R. Castanha ◽  
V. Chu
Keyword(s):  
Substrate Temperature ◽  
Growth Rates ◽  
Chemical Vapor ◽  
High Growth ◽  
Hot Wire ◽  
Microcrystalline Silicon ◽  
Crystalline Fraction ◽  
Lower Growth ◽  
Filament Temperature ◽  
Hydrogen Dilution

AbstractThe effect of hydrogen dilution and substrate temperature on the optoelectronic and structural properties of thin films deposited by hot-wire chemical vapor deposition with filament temperatures between 1900 and 2500 °C from silane and hydrogen are studied. Amorphous silicon films are obtained at high deposition rates for hydrogen dilutions below 90%. The deposition rate scales approximately linearly with the filament temperature in this regime. Microcrystalline films are obtained for hydrogen dilution above 90%, independently of the filament temperature and substrate temperature, with much lower growth rates. The Raman spectrum of these films shows high crystalline fraction and small grain size. High conductivity films, typical of microcrystalline silicon, with high growth rates were achieved by either increasing the substrate temperature at low hydrogen dilution, or by using a hydrogen dilution just at the amorphous to microcrystalline transition point.

The Importance of Comparative Growth Rates in Determining the Canopy Composition of Tasmanian Rainforest

1995 ◽  
Vol 43 (3) ◽  
pp. 243 ◽  
Author(s):  
J Read
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
High Growth ◽  
Forest Stands ◽  
Lower Growth ◽  
Naturally Occurring ◽  
Significant Difference ◽  
Pot Trials ◽  
Canopy Composition ◽  
Study Sites

Growth rates of the rainforest canopy species Atherosperma moschatum Labill., Eucryphia lucida (Labill.) Baill., Nothofagus cunninghamii (Hook.) Oerst., Athrotaxis selaginoides D.Don and Phyllocladus aspleniifolius (Labill.) Hook.f. were measured in naturally-occurring seedlings and in seedlings grown in glasshouse pot trials. The highest field growth rates were recorded in N. cunninghamii on lowland sites on fertile, well-drained soils. On poorer soils, growth rates of N. cunninghamii were lower and there was little difference in growth rates between species. On the most acidic and probably infertile soil, the growth rate of P. aspleniifolius was 1.4 times higher than that of N. cunninghamii, although not significantly different at the 95% level. Similar trends in growth rates were recorded in pot trials. High growth rates were recorded in N. cunninghamii and E. lucida on fertile, well-drained soils, with generally lower growth rates in A. moschatum, P. aspleniifolius and A. selaginoides. No significant difference in growth rate was recorded among N. cunninghamii, E. lucida, A. moschatum and P. aspleniifolius when grown in poor soils or in low nutrient treatments. The trends in comparative growth rates correlate with the measured canopy composition of the study sites. Nothofagus cunninghamii dominates forest stands on sites where it has a clearly superior growth rate compared with co-occurring light-demanding species. Mixed canopies occur on sites where there is little or no difference between species' growth rates. However, not all patterns of canopy dominance can be explained by comparative growth rates alone. For example, P. aspleniifolius commonly dominates forest stands at low to mid-altitude where growth rates of all species are very low, but without necessarily a higher growth rate in P. aspleniifolius than in co-occurring species. The results of the growth rate studies are integrated with some other aspects of the biology of these species in a discussion of the mechanisms determining canopy composition of Tasmanian rainforests.

scholarly journals Ammonia-Hyperproducing Bacteria from New Zealand Ruminants

1998 ◽  
Vol 64 (5) ◽  
pp. 1796-1804 ◽  
Author(s):  
Graeme T. Attwood ◽  
Athol V. Klieve ◽  
Diane Ouwerkerk ◽  
Bharat K. C. Patel
Keyword(s):  
New Zealand ◽  
Dairy Cows ◽  
Dna Sequences ◽  
Phylogenetic Analyses ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Biochemical Tests ◽  
Casamino Acids

ABSTRACT Pasture-grazed dairy cows, deer, and sheep were tested for the presence of ammonia-hyperproducing (HAP) bacteria in roll tubes containing a medium in which tryptone and Casamino Acids were the sole nitrogen and energy sources. Colonies able to grow on this medium represented 5.2, 1.3, and 11.6% of the total bacterial counts of dairy cows, deer, and sheep, respectively. A total of 14 morphologically distinct colonies were purified and studied further. Restriction fragment length polymorphisms of 16S rRNA genes indicated that all isolates differed from the previously described HAP bacteria,Clostridium aminophilum, Clostridium sticklandii, and Peptostreptococcus anaerobius. Carbon source utilization experiments showed that five isolates (C2, D1, D4, D5, and S1) were unable to use any, or very few, of the carbon sources tested. Biochemical tests and phylogenetic analyses of 16S ribosomal DNA sequences indicated that all isolates were monensin sensitive; that D1 and S1 belonged to the genusPeptostreptococcus, that D4 and D5 belonged to the familyBacteroidaceae, where D4 was similar to Fusobacterium necrophorum; and that C2 was most similar to an unidentified species from the genus Eubacterium. Growth on liquid medium containing tryptone and Casamino Acids as the sole nitrogen and energy source showed that D1, D4, and S1 grew rapidly (specific growth rates of 0.40, 0.35, and 0.29 h−1, respectively), while C2 and D5 were slow growers (0.25 and 0.10 h−1, respectively). Ammonia production rates were highest in D1 and D4, which produced 945.5 and 748.3 nmol/min per mg of protein, respectively. Tests of individual nitrogen sources indicated that D1 and D4 grew best on tryptone, S1 grew equally well on Casamino Acids or tryptone, and C2 and D5 grew poorly on all nitrogen sources. The intact proteins casein and gelatin did not support significant growth of any of the isolates. These isolates extend the diversity of known HAP rumen bacteria and indicate the presence of significant HAP bacterial populations in pasture-grazed New Zealand ruminants.

GROWTH OF PIKE-PERCH SANDER LUCIOPERCA (L., 1758) (PERCIDAE) IN RESERVOIRS OF K. SATPAYEV’S CHANNEL

2018 ◽  
pp. 59-68
Author(s):  
Saule Zhangirovna Asylbekova ◽  
Kuanysh Baibulatovich Isbekov ◽  
Vladimir Nickolaevich Krainyuk
Keyword(s):  
Growth Rates ◽  
Growth Dynamics ◽  
High Growth ◽  
Water Bodies ◽  
Volga River ◽  
Trophic Resources ◽  
Pike Perch ◽  
The Amur River ◽  
Back Calculation ◽  
Abiotic And Biotic Factors

Pike-perch is an invader for the water basins of Central Kazakhstan. These species have stable self-reproductive populations in the regional waters. Back calculation method was used to investigate pike-perch growth rates in reservoirs of K. Satpayev’s channel. For comparison, the data from the other water bodies (Vyacheslavsky and Sherubay-Nurinsky water reservoirs) were used, as well as literature data. Pike-perch species from the investigated waters don’t show high growth rates. The populations from the reservoirs of K. Satpayev’s channel have quite similar growth rates with populations from the Amur river, from a number of reservoirs in the Volga river basin and from the reservoir in Spain. Sexual differences in growth have not been observed. Evaluating possible influence of various abiotic and biotic factors on the growth rate of pike-perch in the reservoirs of K. Satpayev’s channel was carried out. It has been stated that the availability of trophic resources cannot play a key role in growth dynamics because of their high abundance. Morphology of water bodies also does not play a role, as well as chromaticity, turbidity and other optical water indicators. It can be supposed that the main factor influencing growth of pike perch is the habitat’s temperature. This factor hardly ever approaches optimal values for the species in reservoirs of K. Satpaev’s channel. The possible influence of fishing selectivity on pike-perch growth rates was also evaluated. Currently, there has been imposed a moratorium on pike-perch catch. However, pike-perch is found in by-catches and in catches of amateur fishermen. It should be said that such seizures have an insignificant role in the dynamics of growth rates.

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