Effect of carbon source on growth rate and phospholipid composition of Escherichia coli 15T− and an unsaturated fatty acid auxotroph

1981 ◽  
Vol 27 (12) ◽  
pp. 1283-1289 ◽  
Author(s):  
James E. Urban ◽  
W. E. Klopfenstein ◽  
K. Ahmad ◽  
J. D. Baines
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Fatty Acid Composition ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Carbon Source ◽  
Acid Composition ◽  
Doubling Time ◽  
Phospholipid Composition ◽  
Acid Supplementation

Escherichia coli 15T− was grown with glucose, succinic acid, aspartic acid, oleic acid, and oleic plus aspartic acids as carbon sources, and a fatty acid auxotroph derived from 15T− was grown on oleic acid and oleic plus aspartic acids. The doubling time, phospholipid composition, phosphorus content, and the fatty acid composition of the phospholipids of cells in each of the media were determined. In all cases, phosphatidylethanolamine was the major phospholipid present; but with 15T− its concentration was inversely proportional to the doubling time in unsupplemented media. With the auxotroph the phosphatidylethanolamine concentration was essentially unchanged with growth. Total lipid phosphorus was inversely proportional to doubling time, an effect particularly evident with the auxotroph. Without oleic acid supplementation, the major effects of carbon source on fatty acid composition are decreases in the content of palmitoleic acid and increases in the content of cis-9,10-methylene hexadecanoic acid as growth rate decreases. Oleic acid supplementation elevated 18:1 fatty acid content in both 15T− and the auxotroph.

Temperature-induced differences in growth rate and fatty acid composition in two strains of Escherichia coli 15T−

1978 ◽  
Vol 24 (10) ◽  
pp. 1277-1280
Author(s):  
John L. Crowe ◽  
James E. Urban
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Unsaturated Fatty Acid ◽  
Growth Temperature ◽  
Doubling Time ◽  
Fatty Acid Ratio ◽  
Acid Ratio

The saturated/unsaturated fatty acid ratio of Escherichia coli 15T− decreases almost threefold as growth temperature decreases from 43 to 27 °C, whereas the ratio of a fast-growing mutant derived from 15T− changes only half as much. Strain 15T− experiences a 2.4-fold change in doubling time across this temperature range, but doubling time in the mutant changes 3.3-fold.

scholarly journals Ethanol-Mediated Variations in Cellular Fatty Acid Composition and Protein Profiles of Two Genotypically Different Strains of Escherichia coli O157:H7

2004 ◽  
Vol 70 (4) ◽  
pp. 2204-2210 ◽  
Author(s):  
R. Y.-Y. Chiou ◽  
R. D. Phillips ◽  
P. Zhao ◽  
M. P. Doyle ◽  
L. R. Beuchat
Keyword(s):  
Escherichia Coli ◽  
Fatty Acid Composition ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Acid Composition ◽  
Cellular Fatty Acid ◽  
Ethanol Stress ◽  
Protein Profiles ◽  
Cellular Fatty Acid Composition ◽  
Stressed Cells

ABSTRACT Two strains of Escherichia coli O157:H7 were grown in tryptic soy broth (TSB, pH 7.1) supplemented with 0, 2.5, 5.0, 7.5, and 10% ethanol at 30°C for up to 54 h. Growth rates in TSB supplemented with 0, 2.5, and 5.0% ethanol decreased with an increase in ethanol concentration. Growth was not observed in TSB supplemented with 7.5 or 10% ethanol. The pH of TSB containing 5.0% ethanol decreased to 5.8 within 12 h and then increased to 7.0 at 54 h. The ethanol content in TSB supplemented with 2.5 or 5.0% ethanol did not change substantially during the first 36 h of incubation but decreased slightly thereafter, indicating utilization or degradation of ethanol by both strains. Glucose was depleted in TSB supplemented with 0, 2.5, or 5.0% ethanol within 12 h. Cells grown under ethanol stress contained a higher amount of fatty acids. With the exceptions of cis-oleic acid and nonadecanoic acid, larger amounts of fatty acid were present in stationary-phase cells of the two strains grown in TSB supplemented with 5.0% ethanol for 30 h than in cells grown in TSB without ethanol for 22 h. The trans-oleic acid content was 10-fold higher in the cells grown in TSB with 5.0% ethanol than those grown in TSB without ethanol. In contrast, cis-oleic acid was not detected in ethanol-stressed cells but was present at concentrations of 0.32 and 0.36 mg/g of cells of the two strains grown in TSB without ethanol. Protein content was higher in ethanol-stressed cells than in nonstressed cells. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein profiles varied qualitatively as affected by the strain and the presence of ethanol in TSB. An ethanol-mediated protein (28 kDa) was observed in the ethanol-stressed cells but not in control cells. It is concluded that the two test strains of E. coli O157:H7 underwent phenotypic modifications in cellular fatty acid composition and protein profiles in response to ethanol stress. The potential for cross protection against subsequent stresses applied in food preservation technologies as a result of these changes is under investigation.

Docosahexaenoic acid supplementation in pregnancy alters placental fatty acid composition

Placenta ◽  
2014 ◽  
Vol 35 (9) ◽  
pp. A70 ◽  
Author(s):  
Theresa L. Powell ◽  
Christiane Meireles ◽  
Vanessa I. Ramirez ◽  
Evelyn Miller ◽  
Kevin W. Hakala ◽  
...  
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Docosahexaenoic Acid ◽  
Acid Composition ◽  
Acid Supplementation ◽  
In Pregnancy

Variability of Seed Fatty Acid Composition to Growing Degree-Days in High Oleic Acid Sunflower Genotypes

Helia ◽  
2015 ◽  
Vol 38 (62) ◽  
Author(s):  
Claudio Ferfuia ◽  
Maurizio Turi ◽  
Gian Paolo Vannozzi
Keyword(s):  
Fatty Acid Composition ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Acid Composition ◽  
Inbred Line ◽  
Acid Content ◽  
Growing Degree Days ◽  
Environment Interaction ◽  
Oleic Acid Content ◽  
Degree Days

AbstractHigh temperature enhances the oleic acid content in the oil of normal cultivars but conflicting results are reported on temperature effects on oleic acid content in HO cultivars: either no effect or an increase in oleic acid content with temperature. To investigate the effects of temperature on HO genotypes under natural field conditions, a three-year field trial was conducted using two sowing dates and three HO genotypes (two inbred lines and one hybrid). To compare our results with previous works, growing degree-days (GDD) were computed (base temperature=6°C). GDD accumulated during the “flowering – 25 days after flowering” period influenced fatty acid composition of seed. Oleic and linoleic acid contents were affected by accumulated GDD in two HO genotypes (one inbred line and the hybrid). There was an increase of about 3% in oleic acid content as response to more high GDD accumulated. Their content was not modified by GDD in the other inbred line. There was a genotype×environment interaction that we suppose depending on modifier genes. These genetic factors affected oleic acid content. This indicated the importance of breeding targeted to select hybrids with a stable oleic acid content and higher than 90%. Saturated fatty acids (palmitic and stearic) were also influenced by temperature, and there was genetic variability among genotypes.

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