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1.
Grace Y. Sun 《Lipids》1979,14(11):918-924
The phospholipid composition and their acyl group profiles from subcellular fractions of guinea pig adrenal gland and the
same fractions from the cortex and medulla of the bovine gland were compared. The phospholipids of guinea pig adrenal were
enriched in diacyl-glycerophosphocholines (GPC) which comprised over 50% of the total phospholipids, but the proportions of
ethanolamine and choline plasmalogens, sphingomyelin and diacyl-glycerophosphoserine (GPS) were lower in guinea pig adrenals
as compared to the bovine adrenals. In the bovine adrenal, sphingomyelin and diacyl-GPS were enriched in the medulla, whereas
diacyl-glycerophosphoinositol (GPI) were enriched in the cortex. Although lysolecithin was present (up to 4.5%) in the bovine
adrenal, only trace amounts of this lipid were detected in the guinea pig adrenal. Characteristic acyl group profiles were
found associated with each type of the phosphoglycerides in adrenal membranes. However, acyl group profiles of the phosphoglycerides
were not greatly different either between the bovine and guinea pig adrenal or with respect to the type of subcellular membranes
isolated. Diacyl-GPC were enriched in 16∶0 and 18∶1, but also contained considerable amounts of 18∶0, 18∶2 and 20∶4. Diacyl-GPE
were enriched in 18∶0, 18∶1 and 20∶4, while diacyl-GPI, diacyl-GPS, as well as alkenylacyl-GPE, were enriched in 20∶4. The
lysolecithin from bovine adrenal membranes contained mainly 16∶0, 18∶0 and 18∶1 with only trace amounts of the polyunsaturated
fatty acids. Other polyunsaturated fatty acids, such as 22∶4 and 22∶6, are apparently not prominent in the phosphoglycerides
from either the bovine or the guinea pig adrenal gland. 相似文献
2.
The distribution of phospholipids as well as their fatty acid compositions of rat mammary tissues were examined during pregnant,
lactating, and post-weaning periods. There was no apparent change in phospholipids and their acyl groups during the early
and late pregnant periods. However, tissue phospholipid composition was different during pregnant, early, and late lactating
periods. After parturition, there was a marked increase in the proportion of diacyl-glycerophosphorylcholine in the phospholipids
of mammary tissue, but this proportion decreased gradually during lactation. The decrease in diacyl-glycerophosphorylcholine
during lactation was marked by a corresponding increase in diacyl-glycerophosphorylethanolamine. Although the shorter chain
fatty acids of triglycerides were increased during lactation, only a small proportion of these fatty acids was found in the
phosphoglycerides. Marked changes in acyl group composition of individual phospholipids are found during these different physiological
stages. In general, there was a rapid decrease in 20∶4 and an increase in 18∶2 in the major phosphoglycerides during parturition.
The proportion of 20∶4 in the phosphoglycerides remained low throughout the entire lactating period, while that of 18∶2 continued
to increase 2–3 fold. Most of the changes in acyl group of the phosphoglycerides during lactation returned to normal ca. 10
days after weaning. A possible relationship of the variation of phospholipid and acyl group compositions in mammary tissue
to changes in hormonal pattern during different physiological stages is discussed. 相似文献
3.
Phospholipids of 27 species of insects representing 6 orders and 20 families were examined by DEAE cellulose column chromatography
to determine the choline/ethanolamine phosphoglyceride ratios, and by gas chromatography to determine the constituent fatty
acids.
The phosphorus in the ethanolamine phosphoglycerides accounted for approximately 50% of the total lipid phosphorus in aphids
(Homoptera) and in all but one family of Diptera (flies) examined while the phosphorus in the choline phosphoglycerides accounted
for only about 25%. Ethanolamine and choline phosphoglycerides were present in approximately equal proportions in one family
of Diptera and in the Coleoptera (beetles) examined. In the other insects examined choline phosphoglycerides predominated,
ethanolamine phosphoglycerides comprising only about 25–30% of total lipid phosphorus as they do in most mammalian tissues.
Diptera in which ethanolamine phosphoglycerides were the major phosphatides were also characterized by high proportions of
fatty acids less than 18 carbons long, particularly palmitoleic acid, in the neutral lipids. Aphids are characterized by a
preponderance of 14-carbon fatty acids. The evidence suggests that predominance of ethanolamine phosphoglycerides is associated
with a preponderance of shorter chain fatty acids in the neutral lipids.
Differences also exist between Diptera and other insects in the fatty acid compositions of different phosphatides, particularly
with respect to the distribution of 18-carbon acids. The compositions observed in insects that contained large amounts of
the choline phosphoglycerides are similar to those found in vertebrates. Similarities in fatty acid composition of the choline
phosphoglycerides in such widely divergent organisms suggest that the fatty acids may play a greater role in phospholipid
function than has heretofore been demonstrated.
Contribution Number I.P.R.I. 74. 相似文献
4.
Phospholipid classes were separated from mouse brain lipid extracts by preparative thin-layer chromatography (TLC). Methyl
esters were prepared from the intact phospholipids by direct transesterification at room temperature in the presence of silica
gel by using 0.5m NaOH-methanol in order to prevent interference by aldehydes or derivatives. Dimethyl acetal derivatives of phosphoglyceride
alkenyl ethers (alkenyl moiety with a double bond in 1,2-position relative to oxygen linkage) were prepared, using 5% concentrated
HCl in methanol, followed by preparative TLC for isolation.
The major phospholipids present were ethanolamine phosphoglycerides (EPG) 39.8%, choline phosphoglycerides (CPG) 39.7%, serine
phosphoglycerides (SPG) 15.0%, and sphingomyelin (Sph) 5.4%. One-fifth of the total phospholipids (PL) were in the form of
plasmalogens, mainly EPG. Choline and serine plasmalogens were present in trace quantities. The major aldehyde components
of the plasmalogens were 16∶0, 18∶0, and 18∶1.
The EPG were rich in long-chain poly-unsaturated fatty acids, including 28.8% of 22∶6 and 17.0% of 20∶4, but contained only
7.2% of 16∶0. In contrast, the CPG contained 39.6% of 16∶0, and 31.0% of 18∶1 with a small content of polyunsaturated fatty
acids. The SPG exhibited a still different pattern containing 38.2% of 18∶0, 23.2% of 18∶1, 24.3% of 22∶6, 2.9% of 16∶0, and
3.8% of 20∶4.
Presented in part at the AOCS Meeting, New Orleans, May 1967. 相似文献
5.
Separation of sterol esters from wax esters in the lipids of vernix caseosa and adult human skin surface was accomplished
by column chromatography on MgO. The fatty acids of the sterol esters and wax esters of both samples were separated into saturates
and monoenes, and examined in detail by gas liquid chromatography (GLC). The saturated fatty acids of the wax esters of vernix
caseosa and of adult human skin surface were remarkably similar. They ranged in chain length from at least C11 to C30, six skeletal types being present: straight even, straight odd, iso, anteiso, other monomethyl branched and dimethyl branched.
A large number of patterns of monoenes were observed, each pattern consisting of desaturation of a specific chain at Δ6 or
Δ9 plus its extension or degradation products. The mole per cent of the total Δ6 and Δ9 patterns of wax ester fatty acid monoenes
of vernix caseosa were 87% and 12%, respectively, and 98% and 1%, respectively, for adult human skin surface lipid. The sterol
ester fatty acids of vernix caseosa were much different from those of adult human skin surface: vernix caseosa saturates were
largely branched and of lengths greater than C18, whereas the saturates of adult human surface lipid resembled the wax ester fatty acids. Of the vernix caseosa monoene patterns,
the mole per cent was 30% Δ6 and 70% Δ9, whereas of the adult human skin surface sterol ester fatty acids 89% were Δ6 and
11% Δ9. Chain extension was particularly pronounced in the sterol ester fatty acid monoenes of vernix caseosa amounting to
7–8 C2 units in some cases. The fatty acids of the sterol esters of both vernix caseosa and adult human skin surface appear to be
derived from the sebaceous gland and from the keratinizing epidermis, but those of the wax esters are from the sebaceous glands
only. 相似文献
6.
(n−3) and (n−6) polyunsaturated fatty acids in the phosphoglycerides of salt-secreting epithelia from two marine fish species 总被引:3,自引:0,他引:3
Fatty acid analyses were carried out on phosphoglycerides isolated from microsomal fractions of the rectal gland of the dogfish,Scyliorthinus canicula, and gills of the cod,Gadus morhua. Ratios of (n−3)/(n−6) polyunsaturated fatty acids were ca. 10 for phosphatidylcholine, (PC), phosphatidylethanolamine (PE)
and phosphatidylserine (PS) from cod gills, reflecting high concentrations of 20∶5 (n−3) and 22∶6(n−3). The ratio for phosphatidylinositol
(PI) from cod gills was 1.3, reflecting high concentrations of 20∶4(n−6) as well as (n−3) polyunsaturates. PC, PE and PS from
rectal glands all had much lower (n−3)/(n−6) ratios than in cod gills, reflecting higher concentrations of 20∶4(n−6), but
the lowest ratio was again present in PI. The latter phospholipid had high concentrations of 18∶0 in both tissues. The relative
constancy of the fatty acid composition of PI in the two salt-secreting tissues and its similarity to mammalian phospholipids
is considered to reflect its specialized role in biomembranes. 相似文献
7.
The acyl composition of ethanolamine and choline phosphoglycerides from a series of human brain tumors was determined and
compared to that of normal human gray matter. Six glioblastomas, one astrocytoma, one oligodendroglioma, and one meningioma
were analyzed. The total fatty acid composition of ethanolamine phosphoglycerides generally had a higher percentage of 18∶1,
18∶2ω6, and 22∶5ω3 and a lower percentage of 22∶6ω3 than that of normal gray matter. Choline phosphoglycerides from the tumors
also contained a higher than normal percentage of 18∶2ω6. Separate analysis of the acyl groups at the 2 position of the diacyl
and ether-linked components of the phosphoglycerides revealed that the diacyl component of ethanolamine phosphoglyceride from
the tumors had lower than normal amount of 22∶6ω3 and a higher than normal amount of 18∶1 and 18∶2ω6. The acyl composition
of ether-linked ethanolamine phosphoglycerides genearally contained a higher percentage of 20∶4ω6 and a lower percentage of
18∶1 compared to the corresponding fraction from normal gray matter. The astrocytoma analyzed had fatty acid profiles similar
to those of the control with the exception of a greater 18∶2ω6 content. These data demonstrate that the composition of the
acyl moiety at the 2 position of diacyl and ether-linked phosphoglycerides of brain tumors differs from the corresponding
component from normal gray matter and that the ether-linked ethanolamine phosphoglycerides provide an important pool of polyunsaturated
fatty acids from brain tumor phospholipids. 相似文献
8.
The lipid composition of Yoshida ascites hepatoma cells was analyzed together with that of ascitic plasma and of livers and
blood plasma from host and normal rats. In comparison to normal livers, host livers showed no significant differences in the
content of the various lipid classes, but contained a higher percentage of palmitic acid and a lower proportion of arachidonic
acid in the major phospholipid classes. In addition, tumor growth induced a marked hypertriglyceridemia in host animals; changes
in the concentration of other plasma lipid classes were not statistically significant. The ascitic plasma contained small
amounts of lipids mainly constituted by cholesteryl esters and phospholipids. Yoshida hepatoma cells contained less phospholipids
in comparison to both host and normal liver, while the increased level of triglycerides and the decrease of free fatty acids
were not statistically significant. Hepatoma cells showed appreciable amounts of ether-linked lipids associated in part to
neutral lipids (as glyceryl ether diesters) and, in part, to ethanolamine and choline phosphoglycerides. The alkyl groups
in GEDE as well as in ethanolamine and choline phosphoglycerides were mainly constituted by C16∶0 and C18∶0 followed by C18∶1. The alk-1-enyl groups in ethanolamine and choline phosphoglycerides were C16∶0 and C18∶0 with only a minor proportion of C18∶1. In comparison to both host and normal liver, Yoshida hepatoma cells showed significant changes in the fatty acid composition
of neutral lipids and phospholipids. Some of the major changes consisted of an increase of monoenoic acids associated with
a decrease of arachidonic and docosahexaenoic acids in phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol. 相似文献
9.
Phosphatidylcholines and phosphatidylethanolamines were isolated from hepatoma 7288CTC, normal liver, and host liver of rats
fed one of the following diets: fat-free diet; fat-free diet supplemented with safflower oil, safflower oil fatty acids, or
partially hydrogenated safflower oil fatty acids; and commercial chow. Thecis andtrans octadecenoate fatty acids were isolated from the 1- and 2-positions of both phosphoglycerides and analyzed quantitatively
for chain positional isomers. Octadecenoates from hepatoma and liver phosphoglycerides of animals fed fat-free or natural
fatsupplemented diets contained almost exclusively twocis isomers: oleic and vaccenic acids. Oleic acid predominated in the 2-position octadecenoates of both phosphoglycerides from
hepatoma and liver. In contrast, vaccenic acid predominated in the 1-position of normal liver phosphatidylcholine and, to
a lesser extent, phosphatidylethanolamine. Host liver and hepatoma exhibited a shift to a higher percentage of oleic acid
at the 1-position. Dietarytrans fatty acids were incorporated predominately in the 1-position of both phosphoglycerides of hepatoma and liver. Except for
thecis Δ10 octadecenoate isomer, all of the unnatural dietarycis isomers between Δ8 and Δ14 were incorporated into the 1-position of the phospholipids, while the unnaturalcis octadecenoates at the 2-position consisted primarily of the Δ12 isomer. Hepatoma phosphoglycerides contained higher percentages
of thetrans Δ10 isomer that was nearly excluded from the 1-position of the two liver phosphoglycerides. All the othertrans octadecenoate isomers were incorporated into the 1-position of both phosphoglycerides, but the small amount oftrans fatty acids incorporated into the 2-position of liver and hepatoma phosphatidylcholine consisted of four isomers, Δ9 to Δ12,
including the Δ10 isomer. Phosphatidylethanolamine exhibited a similar distribution, except for the presence of the Δ13 and
Δ14 isomers at the 2-position. A combination of evidence suggests that the 1-position fatty acids in phosphatidylcholine and
phosphatidylethanolamine are of similar origin. The octadecenoates at the 2-position of these two phosphoglycerides appear
to be of the same origin in hepatoma but not in liver. It was also revealed that the 2-position of hepatoma phosphatidylcholine
contained much higher percentages of palmitate than liver. 相似文献
10.
Boars fed diets containing rapeseed oil for 8 weeks showed significantly higher levels of neutral lipids and similar levels
of phospholipids, compared to those fed corn oil. Erucic and eicosenoic acids were found to be high in ethanolamine phosphoglycerides,
and in particular alkenyl acyl-ethanolamine phosphoglyceride. Furthermore, both long chain monoenes were incorporated preferentially
in position 2 of the choline and ethanolamine phosphoglycerides. The alkenyl group composition of the cardiac lipids of pigs
was influenced by dietary fatty acids. When rapeseed oil was fed, small amounts of 20∶1 and 22∶1 alkenyl constituents were
detected.
Contribution No. 641 Animal Research Institute 相似文献
11.
Lipid metabolism of brain tissue in culture 总被引:2,自引:0,他引:2
John H. Menkes 《Lipids》1972,7(2):135-141
Tissue explants from frontal lobes of rat brain were used for the study of cerebral fatty acid metabolism. After tissues had
been maintained in serum-supplemented medium, a lipid free medium was substituted and metabolic studies were carried out.
Under these conditions explants continued to take up lipid precursors for at least 48 hr. Stearic acid 1-C14, palmitic acid 1-C14 and lignoceric acid 1-C14 were bound to cells as the free fatty acids or incorporafed into neutral lipids (particularly triglycerides), glycolipids
and phospholipids. In the galactolipid fraction, cerebrosides were the principal radioactive lipids. Choline phosphoglycerides,
ethanolamine phosphoglycerides, inositol phosphoglycerides and serine phosphoglycerides were the principal radioactive phospholipids.
Fatty acids were incorporated into cellular lipids either unchanged or after desaturation, chain elongation, or both. In a
patient with a demyelinating disease, precursor uptake was reduced and chain elongation and desaturation of the fatty acid
was diminished. In a patient with generalized GM2 gangliosidosis, glycolipids other than cerebrosides were labeled to a greater extent than normal. These studies exemplify
the usefulness of tissue explants for prolonged metabolic studies in normal and pathological specimens of brain.
One of 13 papers presented at the symposium “Lipid Metabolism in Cells in Culture,” AOCS Meeting, Houston, May, 1971. 相似文献
12.
Gilles Barnathan Joseph Mirallès Emile M. Gaydou Nicole Boury-Esnault Jean-Michel Kornprobst 《Lipids》1992,27(10):779-784
The fatty acid composition of phospholipids from the Senegalese spongeCinachyrella alloclada was examined. Two new fatty acids not hitherto found in nature, namely 10,13-octadecadienoic acid and 16-tricosenoic acid,
were identified. 8-Hexadecenoic, 13-nonadecenoic and 5,9,13-trimethyltretradecanoic fatty acids were also found for the first
time in sponges. The latter compound (1.4% of the total fatty acid mixture), an isoprenoid fatty acid, accompanies the major
fatty acid 4,8,12-trimethyltridecanoic acid (19.7%). The monomethyl branched fatty acids (22%) identified include 23-methylpentacosanoic
acid (anteiso-26∶0), not previously observed in sponged. The major long-chain fatty acids encountered were the known 17-tetracosenoic
19-heptacosadienoic and 5,9,23-tricontatrienoic acid. Some sixty fatty acids were identified as methyl esters andN-acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. 相似文献
13.
The lipids of representative varieties of 2-row spring, 6-row spring, and 6-row winter-type barleys were studied. Total barley
lipids were classified by silicic acid gel column chromatography and separated by thin layer chromatography, and the fatty
acid composition was determined by gas liquid chromatography. Total lipid content of the 6 barley varieties ranged from 3.12%–3.56%
(dry wt basis). The average values for neutral lipids, glycolipids, and phospholipids were 71, 9, and 20%, respectively. The
fatty acid composition of barley was rather typical of plant tissue. The neutral lipids and glycolipids from all the varieties
contained a higher percent of linoleic and linolenic (C 18∶2 and C 18∶3) acids than the phospholipid fraction.
South Dakota Experiment Station Paper 1248. 相似文献
14.
The steryl ester and phospholipid fractions of the marine spongeAgelas conifera were isolated and analyzed. The fatty acyl components of the steryl ester and phospholipid fractions as determined by gas
chromatography and gas chromatography/mass spectrometry were very similar and consisted of 56.8 and 62.7% of C14−C20 acids (normal; branched, especiallyiso andanteiso; and monounsaturated, particularly Δ9 and Δ11 acids) and of 43.1 and 35.5% of C24−C26 acids (Δ5,9 diunsaturated acids), respectively. The major constituent fatty acids detected were 13-methyltetradecanoic,n-hexadecanoic, 10-methylhexadecanoic, 11-octadecenoic, 12-methyloctadecanoic, 5,9-pentacosadienoic and 5,9-hexacosadienoic
acids. The phospholipids isolated were identified as phosphatidylcholine (37%), phosphatidylserine (34%), phosphatidylethanolamine
(16%) and phosphatidylinositol (11%). The distribution of fatty acids within the phospholipid classes was also determined. 相似文献
15.
Gilles Barnathan Pierre Doumenq Jean-Michel Njinkoué Joseph Mirallès Cécile Debitus Claude Lévi Jean-Michel Komprobst 《Lipids》1994,29(4):297-303
The fatty acid composition of phospholipids from the New Caledonian spongeCinachyrella aff.schulzei Keller was studied. More than 60 fatty acids were identified as methyl esters andN-acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. Two isoprenoid fatty acids also were shown
to be present, namely 4,8,12-trimethyltridecanoic and 5,9,13-trimethyltetradecanoic acids. The unusual 6-tetradecenoic, 6-pentadecenoic,
12-nonadecenoic and 26-methylheptacosanoic (iso-28∶0) acids were found for the first time in sponge phospholipids. A series of six n−7 monoenoic long-chain fatty acids (C23 to C28) were identified, including the rare 16-tricosenoic, 18-pentacosenoic and 21-octacosenoic acids. Fifteen fatty acids possessing
the typical 5,9 dienoic moiety accounted for 30% of the total fatty acid mixture. Two new fatty acids were identified, namely
5(Z)-octacosenoic and 27-methyl-5(Z),9(Z)-octacosadienoic (iso-5,9-29∶2). Based on gas chromatography/Fourier transform infrared experiments, the double bonds were assigned the (Z) configuration.
For part 2 of this series, see Reference 1. 相似文献
16.
Edward N. Lambremont 《Lipids》1972,7(8):528-533
When14C-labeled acetate, fatty acids or fatty alcohols were injected into or fed to the tobacco budworm, acyl, alkyl and alk-1-enyl
moieties of the phospholipids incorporated radioactivity. Fatty acids were the principal precursor in acyl bond formation
and fatty alcohols in the synthesis of alkyl and alk-1-enyl glyceryl ethers. Detailed analysis of the etherlinked phosphoglycerides
revealed that most of the radioactivity was in the ethanolamine phosphoglycerides, and very little14C was found in the choline phosphoglycerides. In experiments of a short duration, the alkyl glyceryl ethers incorporated more
radioactivity than the alk-1-enyl glyceryl ethers. The reverse was found with long term experiments, when the alk-1-enyl ethers
had higher radioactivity. In addition to demonstrating the synthesis of ether-linked ethanolamine phosphoglycerides, the data
suggested that fatty alcohols and acids were interconverted by insects and that the alk-1-enyl ethers were derived from the
alkyl ethers.
Presented at the AOCS Meeting, Houston, May 1971.
The following abbreviations and terminology will be used: PE, PC, PI and PS for the generic terms ethanolamine, choline, inositol
and serine phosphoglycerides, respectfully. Alkyl glyceryl ether for 1-alkyl-2-acyl-sn-glycerol-3-phosphoryl-, and alk-1-enyl glyceryl ether for 1-alk-1′-enyl-2-acyl-sn-glycerol-3-phosphoryl-(commonly called plasmalogen). These are adapted from the tentative rules published inJ. Lipid Res. 8:522–528 (1967). 相似文献
17.
Lipids were extracted from the roots and shoots of four species of theCapsicum (pepper) genus and separated into three fractions: triglycerides; free fatty acids, mono- and diglycerides; and phospholipids.
The component fatty acids were determined by subjecting the methyl esters to gasliquid chromatography. The predominate fatty
acids obtained were palmitic (16∶0) and linoleic (18∶2), with lesser amounts of linolenic (18∶3), stearic (18∶1), and oleic
(18∶0). Differences existed in the neutral lipid fractions which might be of value from taxonomic interests; however, the
phospholipids from each of the species and plant parts did not differ so greatly. A comparison of the amount of unsaturated
fatty acids in the phospholipid fractions indicates that differences exist which might be of value in determining the relative
sensitivity of the several species to chilling temperatures. 相似文献
18.
The composition and positional distribution of fatty acids in phospholipids isolated from four locations of a hog carcass
is presented. Variations in fatty acid composition of phospholipids were found depending upon the location in the carcass.
The total unsaturated fatty acid content averaged 34.3 mole % for lecithin, 52.5 mole % for phosphatidylethanolamine, 40.3
mole % for phosphatidylserine and 41.3 mole % in sphingomyelin. The cephalins had a much higher percentage of polyunsaturated
fatty acids than lecithin. The chief saturated fatty acid in lecithin and sphingomyelin was palmitic and in cephalins it was
stearic. A snake venom enzyme preparation(Crotalus adamanteus) hydrolyzed primarily unsaturated fatty acids in phosphoglycerides and the higher the percentage of unsaturation within the
fatty acid the higher percentage of hydrolysis occurred. The unsaturated fatty acids were found chiefly at the theβ-position and the saturated fatty acids at thea-position in the phosphoglycerides.
Michigan State Agricultural Experiment Station Publication No. 3389.
Supported by the U.S. Public Health Service Research Grant No. GM 08801-03. 相似文献
19.
Uptake and metabolism of saturated (16∶0, 18∶0) and unsaturated [18∶1(n−9), 18∶2(n−6), 18∶3(n−3)] fatty acids by cultured
epimastigotes ofTrypanosoma cruzi were studied. Between 17.5 and 33.5% of the total radioactivity of [1-14C]labeled fatty acids initially added to the culture medium was incorporated into the lipids ofT. cruzi and mostly choline and ethanolamine phospholipids. As demonstrated by argentation thin layer chromatography, gas liquid chromatography
and ozonolysis of the fatty acids synthesized, exogenous palmitic acid was elongated to stearic acid, and the latter was desaturated
to oleic acid and 18∶2 fatty acid. The 18∶2 fatty acid was tentatively identified as linoleic acid with the first bond in
the Δ9 position and the second bond toward the terminal methyl end. Exogenous stearic acid was also desaturated to oleic and
18∶2 fatty acid, while oleic acid was only converted into 18∶2. All of the saturated and unsaturated fatty acids investigated
were also converted to a small extent (2–4%) into polyunsaturated fatty acids. No radioactive aldehyde methyl ester fragments
of less than nine carbon atoms were detected after ozonolysis of any of the fatty acids studied. These results demonstrate
the existence of Δ9 and either Δ12 or Δ15 desaturases, or both, inT. cruzi and suggest that Δ6 desaturase or other desaturases of the animal type are likely absent in cultured forms of this organism. 相似文献
20.
Striking differences were found in the compartmentalization of fatty acids into liver lipid fractions. The saturated fatty
acids—lauric, myristic, palmitic and stearic—were incorporated into phosphoglycerides at faster rates with increasing chain
lengths, while triglyceride incorporation was almost uniform. The degree of incorporation of the unsaturated fatty acids into
phosphoglycerides (structural) compared to triglyceride (storage and energy) was the converse of their oxidation rates. The
incorporation of oleic, linoleic and α-linolenic acids was mainly into triglyceride, whereas dihomo-γ-linolenic acid and arachidonic
acid were preferentially incorporated into phosphoglycerides. The data suggest that distribution of each fatty acid is different
depending on its destination for structural or energy function. 相似文献