Split Defect of Swiss Cheese

1975 ◽  
Vol 38 (1) ◽  
pp. 31-35 ◽  
Author(s):  
D. H. HETTINGA ◽  
G. W. REINBOLD
Keyword(s):  
Low Temperature ◽  
Malate Dehydrogenase ◽  
Low Temperatures ◽  
Specific Activity ◽  
Preceding Paper ◽  
Co2 Production ◽  
Swiss Cheese ◽  
Temperature Growth ◽  
Metabolic Characteristics ◽  
Specific Activities

In a preceding paper we reported that certain strains of Propionibacterium which grow at low temperatures are able to split Swiss cheese. The metabolic characteristics of these strains differ from those of strains unable to grow and produce CO2 at low temperatures. The optimal pH for malate dehydrogenase activity of cell-free extracts of the low-temperature growing strains was 7.5, whereas it was 8.5 for strains lacking the ability to grow at low temperatures. Arrhenius plots of enzymic specific activity for lactate and malate dehydrogenases of cell-free extracts obtained from low-temperature growing strains showed greatest activities at temperatures below 10 C. At 15 C or greater, cell-free extracts of strains without low-temperature growth ability showed equal or greater lactate or malate dehydrogenase specific activities. Thus, enzymes of low-temperature growing strains showed greater capacities for activity at both lower temperatures and lower pH. These data support the hypothesis that such strains at low temperature are capable of CO2 production which creates a predisposition for Swiss cheese to split when stored at temperatures of 10 C or lower.

SPLIT DEFECT OF SWISS CHEESE

1974 ◽  
Vol 37 (6) ◽  
pp. 322-328 ◽  
Author(s):  
D. H. Hettinga ◽  
G. W. Reinbold ◽  
E. R. Vedamuthu
Keyword(s):  
Low Temperatures ◽  
Gas Permeability ◽  
Sugar Content ◽  
Carbon Dioxide Production ◽  
Co2 Production ◽  
Swiss Cheese ◽  
Temperature Growth ◽  
Cold Room ◽  
High Incidence ◽  
Growth Ability

When strains of propionibacteria able to grow at 3.8 C were used in Swiss cheese manufacture, resulting 3- and 6-month-old cheeses had a high incidence of splits (6 of 13 and 10 of 13 lots, respectively). With strains lacking this low-temperature growth ability, only 1 of 10 and 2 of 10 lots of cheese split after comparable curing periods. Degree of cheese proteolysis, moisture, and sugar content could not be related to Propionibacterium strain used nor to split incidence. Carbon dioxide production in the warm (21 C) room by strains able to grow at low temperatures was essentially twice that of strains lacking this ability. This CO2 production difference between strains was maintained during subsequent cold-room curing. Type of cheese-wrapping film also affected split incidence. Commercially manufactured cheeses wrapped in four films of differing gas permeability showed a distinct tendency toward splitting in the films impermeable to oxygen.

scholarly journals Psychrobacter arcticus 273-4 Uses Resource Efficiency and Molecular Motion Adaptations for Subzero Temperature Growth

2009 ◽  
Vol 191 (7) ◽  
pp. 2340-2352 ◽  
Author(s):  
Peter W. Bergholz ◽  
Corien Bakermans ◽  
James M. Tiedje
Keyword(s):  
Gene Expression ◽  
Energy Metabolism ◽  
Low Temperature ◽  
Low Temperatures ◽  
Extreme Environments ◽  
Resource Efficiency ◽  
Subzero Temperature ◽  
Rna Helicases ◽  
Temperature Growth ◽  
Peptidyl Prolyl Isomerases

ABSTRACT Permafrost soils are extreme environments that exert low-temperature, desiccation, and starvation stress on bacteria over thousands to millions of years. To understand how Psychrobacter arcticus 273-4 survived for >20,000 years in permafrost, transcriptome analysis was performed during growth at 22°C, 17°C, 0°C, and −6°C using a mixed-effects analysis of variance model. Genes for transcription, translation, energy production, and most biosynthetic pathways were downregulated at low temperatures. Evidence of isozyme exchange was detected over temperature for d-alanyl-d-alanine carboxypeptidases (dac1 and dac2), DEAD-box RNA helicases (csdA and Psyc_0943), and energy-efficient substrate incorporation pathways for ammonium and acetate. Specific functions were compensated by upregulation of genes at low temperature, including genes for the biosynthesis of proline, tryptophan, and methionine. RNases and peptidases were generally upregulated at low temperatures. Changes in energy metabolism, amino acid metabolism, and RNase gene expression were consistent with induction of a resource efficiency response. In contrast to results observed for other psychrophiles and mesophiles, only clpB and hsp33 were upregulated at low temperature, and there was no upregulation of other chaperones and peptidyl-prolyl isomerases. relA, csdA, and dac2 knockout mutants grew more slowly at low temperature, but a dac1 mutant grew more slowly at 17°C. The combined data suggest that the basal biological machinery, including translation, transcription, and energy metabolism, is well adapted to function across the growth range of P. arcticus from −6°C to 22°C, and temperature compensation by gene expression was employed to address specific challenges to low-temperature growth.

scholarly journals The effects of grass and concentrate diets on the specific activities of some enzymes of hepatic carbohydrate metabolism in sheep

1976 ◽  
Vol 35 (3) ◽  
pp. 407-411 ◽  
Author(s):  
J. Pearce ◽  
E. F. Unsworth
Keyword(s):  
Carbohydrate Metabolism ◽  
Malate Dehydrogenase ◽  
Specific Activity ◽  
Glycolytic Enzymes ◽  
Phosphogluconate Dehydrogenase ◽  
Specific Activities ◽  
Glucose 6 Phosphate Dehydrogenase

1. Feeding sheep a concentrate diet compared with grass diets increased the hepatic specific activities of the three glycolytic enzymes studied, and that of glucose-6-phosphate dehydrogenase (EC 1.1.1.49), and reduced the specific activity of D-fructose-1,6-diphosphate 1-phosphohydrolase (EC 3.1.3.11). The specific activities of phosphogluconate dehydrogenase (EC 1.1.1.43) and malate dehydrogenase (decarboxylating) (NADP) (EC 1.1.1.40) were unaffected by diet.

LOW-TEMPERATURE GROWTH RESPONSES OF THE TOMATO

1968 ◽  
Vol 48 (3) ◽  
pp. 281-286 ◽  
Author(s):  
G. A. Kemp
Keyword(s):  
Growth Rate ◽  
Seed Germination ◽  
Low Temperature ◽  
Seedling Growth ◽  
Low Temperatures ◽  
Fruit Set ◽  
Growth Responses ◽  
Growth Phases ◽  
Night Temperature ◽  
Temperature Growth

The effects of low temperatures on several growth phases of the tomato were studied. The tests, each conducted over a 2-week period, included seed germination at 8.5 °C, rate of seedling growth at a night temperature of 10 °C, root and top growth of plants in soil at 15 °C, and fruit set at a night temperature of 4.5 °C.Varietal response to growth rate at low temperatures differed in all phases studied, and varieties that performed well in some phases did not always perform well in others. Of the varieties studied, six grew well under most of the low-temperature conditions. These were: Earlinorth, Bonita, Azerbidzivisky, P.I. 205040, P.I. 280597, and Cold Set.

Effect of the carbon source and cyclic AMP on isocitrate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase in Klebsiella pneumoniae C3

1982 ◽  
Vol 28 (10) ◽  
pp. 1101-1106 ◽  
Author(s):  
A. Juarez ◽  
R. Parés ◽  
J. Vives-Rego
Keyword(s):  
Klebsiella Pneumoniae ◽  
Stationary Phase ◽  
Succinate Dehydrogenase ◽  
Malate Dehydrogenase ◽  
Isocitrate Dehydrogenase ◽  
Specific Activity ◽  
Exponential Growth Phase ◽  
Specific Activities ◽  
In The Beginning ◽  
Excess Glucose

When strain C3 of Klebsiella pneumoniae is grown on a minimal medium with excess glucose, isocitrate dehydrogenase, malate dehydrogenase, and succinate dehydrogenase specific activities increase in the last period of the exponential growth phase and in the beginning of the stationary phase. Glucose exhaustion does not alter the development of malate dehydrogenase and succinate dehydrogenase, but specific activities are higher than those obtained with excess glucose. In contrast, glucose exhaustion can be correlated with a decrease of isocitrate dehydrogenase specific activity in the stationary phase. Induction of strain C3 isocitrate dehydrogenase by glucose in complex medium and repression by cAMP in mineral medium were observed. Glucose induction and the NADP/NADPH ratio are suggested as regulatory mechanisms controlling isocitrate dehydrogenase synthesis in the Enterobacteriaceae, but the former appears to be restricted to some Klebsiella strains.

Low-Temperature Growth of Thin Films of A12O3 with Trimethylaluminum and Hydrogen Peroxide

1991 ◽  
Vol 222 ◽  
Author(s):  
J. F. Fan ◽  
K. Sugioka ◽  
K. Toyoda
Keyword(s):  
Thin Films ◽  
Hydrogen Peroxide ◽  
Low Temperature ◽  
Chemical Reaction ◽  
Low Temperatures ◽  
Arbitrary Shape ◽  
Room Temperature ◽  
Surface Chemical ◽  
Surface Chemical Reaction ◽  
Temperature Growth

ABSTRACTThin films of A12O3 were prepared by sequential surface chemical reaction of trimethylaluminum and hydrogen peroxide at low temperatures. It has been found that hydrogen peroxide reacts very easily with trimethylaluminum, resulting in growth of A12O3 at the temperature as low as the room temperature. Another favorable feature of the technique is that the growth of excellent A12O3 occurs identically wherever the reactants reach, making it possible to completely coat the surface of the sample with arbitrary shape.

Low Temperature Growth of GaAs and AlGaAs by Mombe

1991 ◽  
Vol 240 ◽  
Author(s):  
C. R. Abernathy ◽  
D. A. Bohling ◽  
A. C. Jones
Keyword(s):  
Low Temperature ◽  
Low Temperatures ◽  
Molecular Beam ◽  
Hydrogen Plasma ◽  
Growth Efficiency ◽  
Carbon Uptake ◽  
High Carbon ◽  
Temperature Growth ◽  
Metal Organic ◽  
Amine Compounds

ABSTRACTWe have examined various methods of overcoming the problems of low growth efficiency and high carbon uptake which occur when GaAs is grown at low temperatures by Metal Organic Molecular Beam Epitaxy (MOMBE). We have found that removal of the carbon through conventional means such as precracking or interaction with hydrogen is not effective in enhancing the carbon removal process. In fact, the use of a hydrogen plasma during growth actually increases the carbon background due to a reduction in the surface V/III ratio. Greater success is obtained when alternative precursors are used as replacements for AsH3 and triethylgallium (TEG). Tris-dimethylaminoarsenic (DMAAs) offers reduced carbon uptake through formation of amine compounds while tri-isobutylgallium (TTBG) shows better efficiency and less carbon than TEG at low growth temperature.

Relatively Low Temperature Growth of Carbon Nanotubes by Thermal Chemical Vapor Deposition using Novel Catalysts

2006 ◽  
Vol 922 ◽  
Author(s):  
Han-Chung Tai ◽  
Kao-Chao Lin ◽  
Tsung-Ying Chuang ◽  
Yao-Ren Chang ◽  
Rui-Ling Lai ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Low Temperature ◽  
Vapor Deposition ◽  
Low Temperatures ◽  
Chemical Vapor ◽  
Large Area ◽  
Field Emission Display ◽  
Temperature Growth ◽  
Thermal Chemical Vapor Deposition ◽  
Turn On

AbstractWe found out the promising catalyst materials(NiPd). The NiPd not only has the low melting point but also has the Pd enhancing the surface diffusion at low temperatures(<500'c ). With the Pd film thickness increasing, we could control the CNT density and synthesize more aligned and uniform CNTs. We also obtained the better electrical properties including lower turn-on field (3.4 V/um) and higher current density (34.3 mA/cm2) for NiPd as catalyst. For the advantages described above, we believe that the difficulty of low temperature on FED can be overcome. Further, the large area field emission display might be fabricated in the future.

EFFECT OF pH ON LOW TEMPERATURE GROWTH OF SALMONELLA1

1972 ◽  
Vol 35 (1) ◽  
pp. 49-52 ◽  
Author(s):  
J. R. Matches ◽  
J. Liston
Keyword(s):  
Low Temperature ◽  
Growth Temperature ◽  
Low Temperatures ◽  
Food Poisoning ◽  
Combined Effects ◽  
Temperature Growth ◽  
Ph Values ◽  
Effects Of Ph ◽  
Salmonella Serotypes ◽  
Ph Range

The combined effects of pH and temperature on growth of three serotypes of salmonellae are reported. Salmonela heidelberg grew on the surface of agar over the pH range of 5.0 to 9.0. Minimum growth temperatures of 5.3, 5.2, and 5.3 C were obtained at pH values of 6.0, 7.0, and 8.0, respectively. In broth, S. heidelberg increased in number over the pH range of 6.0 to 8.0, with the lowest growth temperature of 6.0 C obtained at pH 7.0. Salmonella typhimurium increased in number in broth at pH values of 6.0 to 9.0. A time-temperature effect was shown by this organism after 16 days. Salmonella derby grew over the pH range of 6.0 to 8.0 in broth, with the lowest growth temperature of 9.0 C obtained at pH 6.0 and pH 7.0. The results indicate that food-poisoning Salmonella serotypes grow only over a narrow pH range at low temperatures.

Magnetic Cooperative Phenomenon with Unpaired sp-Electrons System by MBE Low-Temperature Growth

2019 ◽  
Vol 290 ◽  
pp. 336-341
Author(s):  
Mohd Ambri Mohamed ◽  
Burhanuddin Yeop Majlis
Keyword(s):  
Low Temperature ◽  
Low Temperatures ◽  
Molecular Beam ◽  
Electronic Devices ◽  
High Concentration ◽  
Temperature Growth ◽  
Cooperative Phenomenon ◽  
High Concentrations ◽  
Cooperative Transition ◽  
Synthesis Of Materials

We present a new possibility of crystal growth as synthesis of materials containing high concentrations of unpaired sp electrons by growth of Be doped Gallium Arsenides at low temperatures of 200-3000C using Molecular Beam Epitaxy (MBE) and investigate a possibility of applications of magnetotransport properties based on these unpaired sp-electrons to spintronics devices.The present study using high concentration of unpaired sp-electrons by the growth of Beryllium-doped GaAs layers at low temperatures resulted in a cooperative transition of localized spins at low temperature and also affected the mechasnism of tranport properties of the sample from hopping conduction to valence band conduction.This attempts will give rise to a possibility of adding new functions to existing electronic devices.

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