Rose A. Gelman

Characterization and metabolism of free fatty alcohols fromEscherichia coli

Free fatty acohols have been established as lipid components ofE. coli K-12. Using combined gas liquid chromatography-mass spectrometry, the major alcohols in aerobically grown cells were identified as 1-tetradecanol (18%), 1-hexadecanol (28%), 1-octadecanol (14%), and 2-pentadecanol (27%). Small amounts of 1-hexadecenol (3%), 2-tridecanol (8%), and 2-tetradecanol (1.5%) were also detected. Analysis of anaerobically grown cells has shown a selective decrease of the secondary alcohols. 2-Pentadecanol was present as only 7% of the total alcohol fraction, and only traces of 2-tridecanol and 2-tetradecanol were found. The major alcohols in anaerobic cells were 1-tetradecanol, 1-pentadecanol, 1-hexadecenol and 1-hexadecanol. The above observations strongly suggest two pathways for the synthesis of fatty alcohols inE. coli. One pathway synthesizes the primary alcohols and does not require molecular oxygen, and a separate pathway synthesizes the secondary alcohols and has a requirement for molecular oxygen.

Effects of different culture media and oxygen upon lipids ofEscherichia coli K-12

The effects of altering the chemical composition of the culture media and the oxygen content of the environment upon the lipid metabolism ofEscherichia coli K-12 were investigated. WhenE. coli cells were grown on the same culture medium but under aerobic and anaerobic conditions, an increase in the free fatty acids of anaerobically grown cells was observed with a disproportionate increase in the unsaturated fatty acids. When glucose was the sole carbon source, both fatty alcohols and hydrocarbons were detected as component lipids of these cells, whether growth occurred under aerobic or anaerobic conditions. Based upon this observation, acetate is considered the initial precursor for fatty alcohol and hydrocarbon biosynthesis. A possible metabolic pathway involving fatty alcohols in hydrocarbon synthesis has been postulated.

In vivo and in vitro biosynthesis of free fatty alcohols inEscherichia Coli K-12

In vivo studies have indicated that exogenous free fatty acids may serve as precursors of the free fatty alcohols ofEscherichia coli K-12. Following disruption of the cells, the enzymatic activity capable of catalyzing the reduction of long chain fatty aldehydes to fatty alcohols was localized in the 100,000 x g supernatant fraction. Nicotinamide adenine dinucleotide phosphate, reduced form, was the required cofactor. The product of the reaction was characterized rigorously as 1-hexadecanol when hexadecanal was the substrate. Three independent, but complementary, assay methods were developed to assay the aldehyde reductase activity. By employing these methods, an equivalence between nicotinamide adenine dinucleotide phosphate, reduced form, oxidation and 1-hexadecanol synthesis was established. Two protein fractions catalyzing the reduction of fatty aldehydes to fatty alcohols were detected in the 100,000 x g supernatant fraction following ammonium sulfate fractionation and diethylaminoethyl-cellulose chromatography. Enzymatic activity (70%) applied to the diethylamino-ethyl-cellulose column was eluted at a phosphate concentration of 0.115 M. The remaining 30% was eluted at a concentration of 0.23 M. Following sephadex chromatography, it was observed that the enzyme eluting at 0.115 M phosphate had an apparent mol wt of 250,000 Daltons while that eluting at 0.23 M had an apparent mol wt of 62,000 Daltons. The enzymes were similar with respect to substrate specificity, pH optima, ionic strength optima, and stability with respect to thiol inhibitors, suggesting different sized aggregates of similar subunits.

The quantitative and qualitative analysis of alkyl α-glycerol ethers as alkoxy acetaldehydes

Abstract A simple procedure is described for the qualitative and quantitative analysis of alkyl α-glycerol ethers as their corresponding alkoxy acetaldehydes. This method is advantageous in that the same derivative may be utilized for both quantitative and qualitative analysis. Moreover, the sensitivity of this procedure is greater than previously published spectrophotometric methods.

Permeability of the Blood-Brain Barrier to Long-Chain Alcohols from Plasma

Cis-9-octadecenyl alcohol was fed as a dietary supplement to adult male rats for 7 and 14 days. At the end of these feeding intervals, lipids were extracted from brain and liver. The neutral lipids were analyzed for free and esterified long-chain alcohols and alkyl and alk-1-enyl glycerols. Total lipid phosphorus, alkyl acyl and alk-1-enyl acyl phosphoglycerides were determined in the phospholipid fraction. A marked change was observed in these lipid types in the liver, but not in the brain. In liver the free and esterified long-chain alcohols increased threefold following feeding of the dietary supplement. Feeding cis-9-octadecenyl alcohol had no effect on the neutral alkoxy lipids of liver but resulted in an approximately three- to eightfold increase in the ionic alkoxy lipids.

Free fatty aldehydes in serum

Abstract Free fatty aldehydes have been demonstrated to occur as a component of the lipids of normal human serum varying in amount from 0.8 to 2.4 μM per liter.

Serum Long-Chain Alcohol Levels in Healthy Individuals and in Patients with Breast Cancer

Total long-chain alcohols were analyzed in blood sera from normal individuals and patients with diagnosed breast cancer. Tetra-, hexa- and octadecan-1-ol were the major long-chain alcohols detected in both groups. While the qualitative composition of the serum alcohols was similar in the two groups the average alcohol content of the serum of the breast cancer patients was approximately six times greater than that of the normal group. This difference in serum alcohol levels between the two groups was significant at p less than 0.01.

Inhibition of growth of Morris hepatomas 7777 and 7800 by corn oil.

Intraperitoneal injection of trace amounts of corn oil prior to and following the injection of 40-50 mg of tissue from hepatoma 7777 or 7800 into the thigh of adult male Buffalo rats resulted in a marked decrease in the growth rate of both tumors. Exhaustive extraction of the corn oil with water indicated that the active component was not water soluble. Similar injections of safflower oil or isotonic saline had no effect on tumor growth rate. Analysis of the tissue phospholipid fatty acids revealed that the injected corn oil caused no change in the esterified fatty acids in this lipid fraction.