Desaturation of linoleic acid from exogenous lipids by isolated chloroplasts.
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ABSTRACT:
SUBMITTER: Jones AV
PROVIDER: S-EPMC1162169 | biostudies-other | 1980 Sep
REPOSITORIES: biostudies-other
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Project description:Analysis of Lactobacilli evolved in a mouse and in vivo in the presence of 18:2
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Project description:Microsomes isolated from liver and brain tissue were assayed to examine transitions in metabolic capability to synthesize chain elongation-desaturation products of C18:2(9,12) during the perinatal development of the pig. Microsomal synthesis of trienes, tetraenes and pentaenes was compared for fetal, neonatal and postnatal piglets. Rates of synthesis of tetraenes and pentaenes by chain elongation-desaturation of C18:2(9,12) were greatest in liver. During the later half of gestation, the capability to synthesize tetraenes increased 2-3-fold on a per mg of microsomal protein basis. Increase in the capacity to synthesize tetraenes suggests a significant transition in the activity of delta 5 desaturase during the last half of gestation. For brain, synthesis of C22:5(4,7,10,13,16) from C18:2(9,12) was greatest at term. These observations indicate that in liver and brain the capability to chain elongate-desaturate C18:2(9,12) to longer chain homologues increases significantly during early development. It is suggested that during gestation the activity of the delta 5 desaturase limits synthesis of C20 and C22 homologues of C18:2(9,12). The metabolic conversion of C20 and C22 fatty acids by chain elongation of C20:4(5,8,11,14) does not appear to limit the synthesis of very long chain homologues of linoleic acid in fetal liver or brain.
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Project description:Ether lipids are ubiquitous constituents of cellular membranes with no discrete cell biological function assigned yet. Using fluorescent polyene-ether lipids we analyzed their intracellular distribution in living cells by microscopy. Mitochondria and the endoplasmic reticulum accumulated high amounts of ether-phosphatidylcholine and ether-phosphatidylethanolamine. Both lipids were specifically labeled using the corresponding lyso-ether lipids, which we established as supreme precursors for lipid tagging. Polyfosine, a fluorescent analogue of the anti-neoplastic ether lipid edelfosine, accumulated to mitochondria and induced morphological changes and cellular apoptosis. These data indicate that edelfosine could exert its pro-apoptotic power by targeting and damaging mitochondria and thereby inducing cellular apoptosis. In general, this study implies an important role of mitochondria in ether lipid metabolism and intracellular ether lipid trafficking.
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Project description:OBJECTIVE:The present investigation was aimed to explore the potential of lactobacilli for conjugated linoleic acid (CLA) production, isolated from rumen fluid samples of lactating goats. METHODS:A total of 64 isolates of lactobacilli were obtained using deMan-Rogosa-Sharpe (MRS) agar from rumen fluid of goats and further subjected to morphological and biochemical characterizations. Isolates found as gram-positive, catalase negative rods were presumptively identified as Lactobacillus species and further confirmed by genus specific polymerase chain reaction (PCR). The phylogenetic tree was constructed from the nucleotide sequences using MEGA6. RESULTS:Out of the 64 isolates, 23 isolates were observed positive for CLA production by linoleate isomerase gene-based amplification and quantitatively by UV-spectrophotometric assay for the conversion of linoleic acid to CLA as well as gas chromatography-based assay. In all Lactobacillus species cis9, trans11 isomer was observed as the most predominant CLA isomer. These positive isolates were identified by 16S rRNA gene-based PCR sequencing and identified to be different species of L. ingluviei (2), L.salivarius (2), L. curvatus (15), and L. sakei (4). CONCLUSION:The findings of the present study concluded that lactic acid bacteria isolated from ruminal fluid samples of goat have the potential to produce bioactive CLA and may be applied as a direct fed microbial to enhance the nutraceutical value of animal food products.
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Project description:1. Chloroplasts prepared by the non-aqueous technique will, after fragmentation by ultrasonic treatment, incorporate [2-(14)C]mevalonic acid into phytoene, the first C(40) compound formed in the biosynthetic sequence to coloured carotenoids. 2. With suspensions containing 3.5mg. of chlorophyll, the optimum amounts of cofactor required were ATP (10mumoles), magnesium chloride (20mumoles) and glutathione (20mumoles); neither NAD(+) nor NADP(+) was required. 3. Very small amounts of squalene are also formed and synthesis is stimulated by addition of NADH or NADPH. Phytoene synthesis was not affected by the presence of these cofactors and no lycopersene (the C(40) homologue of squalene) was detected. 4. The phytol side chain of chlorophyll is also labelled under these conditions. 5. Preparations of developing chloroplasts are more active than preparations of mature chloroplasts.
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