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1.
The composition of fatty acids (FAs) of a green alga (Ulva intestinalis) inhabiting small rivers of the Elton Lake basin has been investigated. It has been established that long-chain FAs with 16 and 18 carbon atoms are essential. We have investigated the composition variability of FAs of lipids of U. intestinalis depending on environmental factors: the level of mineralization, temperature, oxygen saturation, and acidity. It has been revealed that FA nonsaturation increases with an increase in mineralization. We assume that ω-6 and ω-3 desaturases participate in the adaptation of U. intestinalis to this factor.  相似文献   

2.
Polysaccharide and lipid composition of the Pacific brown seaweed Laminaria gurjanovae is determined. Alginic acid is shown to be the main polysaccharide of its biomass (about 28%); it consists of mannuronic and guluronic acid residues at a ratio of 3: 1. The yield of water-soluble polymannuronic acid is low and does not exceed 1.1% of dry biomass. High laminaran content (about 22%) is found, whereas the yield of fucoidan is no more than 3.6%. Laminaran consists of two fractions, soluble and insoluble in cold water, their ratio is 2.5: 1. Insoluble laminaran is a practically linear 1,3-β-D-glucan, and the soluble fraction was shown to be 1,3;1,6-β-D-glucan. The oligosaccharide products of desulfation or partial acidic hydrolysis of fucoidan were studied by MALDI TOF MS; they were found to be fuco- and galactooligosaccharides. The fucoidan is suggested to be a highly sulfated partially acetylated galactofucan (Fuc/Gal is ~1: 1). The main lipid components of the dried L. gurjanovae are neutral lipids and glyceroglycolipids, whereas phospholipids are found in minor amounts. The main fatty acid components of lipids are 14:0, 16:0, 16:1 ω-7, 18:1 ω-7 and 18:2 ω-6 acids.  相似文献   

3.
The fatty acid distributions at the sn-1 and sn-2 positions in major chloroplast lipids of Chlorella kessleri 11h, monogalactosyl diacylglycerol (MGDG) and digalactosyl diacylglycerol (DGDG), were determined to show the coexistence of both C16 and C18 acids at the sn-2 position, i.e. of prokaryotic and eukaryotic types in these galactolipids. For investigation of the biosynthetic pathway for glycerolipids in C. kessleri 11h, cells were fed with [14C]acetate for 30 min, and then the distribution of the radioactivity among glycerolipids and their constituent fatty acids during the subsequent chase period was determined. MGDG and DGDG were labeled predominantly as the sn-1-C18-sn-2-C16 (C18/C16) species as early as by the start of the chase, which suggested the synthesis of these lipids within chloroplasts via a prokaryotic pathway. On the other hand, the sn-1-C18-sn-2-C18 (C18/C18) species of these galactolipids gradually gained radioactivity at later times, concomitant with a decrease in the radioactivity of the C18/C18 species of phosphatidylcholine (PC). The change at later times can be explained by the conversion of the C18/C18 species of PC into galactolipids through a eukaryotic pathway. The results showed that C. kessleri 11h, distinct from most of other green algal species that were postulated mainly to use a prokaryotic pathway for the synthesis of chloroplast lipids, is similar to a group of higher plants designated as 16:3 plants in terms of the cooperation of prokaryotic and eukaryotic pathways to synthesize chloroplast lipids. We propose that the physiological function of the eukaryotic pathway in C. kessleri 11h is to supply chloroplast membranes with 18:3/18:3-MGDG for their functioning, and that the acquisition of a eukaryotic pathway by green algae was favorable for evolution into land plants.  相似文献   

4.
Two Gram-stain-negative, facultative anaerobic, motile, rod-shaped strains, S-B4-1UT and JOB-63a, forming small whitish transparent colonies on marine agar, were isolated from a sponge of the genus Haliclona. The strains shared 99.7% 16S rRNA gene sequence identity and a DNA-DNA hybridization value of 100%, but were differentiated by genomic fingerprinting using rep-PCRs. 16S rRNA gene sequence phylogeny placed the strains as a sister branch to the monophyletic genus Endozoicomonas (Oceanospirillales; Gammaproteobacteria) with 92.3–94.3% 16S rRNA gene sequence similarity to Endozoicomonas spp., 91.9 and 92.1% to Candidatus Endonucleobacter bathymodiolin, and 91.9 to 92.1% to the type strains of Kistimonas spp. Core genome based phylogeny of strain S-B4-1UT confirmed the phylogenetic placement. Major fatty acids were summed feature 3 (C16:1 ω7c/C16:1 ω6c) and 8 (C18:1 ω7c/C18:1 ω6c) followed by C10:0 3-OH, C16:0, and C18:0. The G + C content was 50.1–51.4 mol%. The peptidoglycan diamino acid of strain S-B4-1UT was meso-diaminopimelic acid, the predominant polyamine spermidine, the major respiratory quinone ubiquinone Q-9; phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine were major polar lipids. Based on the clear phylogenetic distinction, the genus Parendozoicomonas gen. nov. is proposed, with Parendozoicomonas haliclonae sp. nov. as type species and strain S-B4-1UT (= CCM 8713T = DSM 103671T = LMG 29769T) as type strain and JOB-63a as a second strain of the species. Based on the 16S rRNA gene sequence phylogeny of the Oceanospirillales within the Gammaproteobacteria, the Endozoicomonaceae fam. nov. is proposed including the genera Endozoicomonas, Parendozoicomonas, and Kistimonas as well as the Candidatus genus Endonucleobacter.  相似文献   

5.
The monomeric composition of the suberins from 16 species of higher plants was determined by chromatographic methods following depolymerization of the isolated extractive-free cork layers with sodium methoxide-methanol. 1-Alkanols (mainly C18C28), alkanoic (mainly C16C30), α,ω-alkanedioic (mainly C16C24), ω-hydroxyalkanoic (mainly C16C21), dihydroxyhexadecanoic (mainly 10,16-dihydroxy- and 16-dihydroxyhexadecanoic), monohydroxyepoxyalkanoic (9,10-epoxy-18-hydroxyoctadecanoic), trihydroxyalkanoic (9,10, 18-trihydroxyoctadecanoic), epoxyalkanedioic (9,10-epoxyoctadecane-1,18-dioic) and dihydroxyalkanedioic (9,10-dihydroxyoctadecane-1 18-dioic) acids were detected in all species. The suberins differed from one another mainly in the relative proportions of these monomer classes and in the homologue content of their 1-alkanol, alkanoic, α,ω-alkanedioic and ω-hydroxyalkanoic acid fractions. C18 epoxy and vic-diol monomers were major components (32–59%) of half of the suberins examined (Quercus robur, Q. ilex, Q. suber, Fagus sylvatica, Castanea sativa, Betula pendula, Acer griseum, Fraxinus excelsior) where as ω-hydroxyalkanoic and α,ω-alkanedioic acids predominated in those that contained smaller quantities of such polar C18 monomers (Acer pseudoplatanus, Ribes nigrum, Euonymus alatus, Populus tremula, Solanum tuberosum, Sambucus nigra, Laburnum anagyroides, Cupressus leylandii). All species, however, contained substantial amounts (14–55 %) of ω-hydroxyalkanoic acids, the most common homologues being 18:1 (9) and 22: 0. The dominant α,ω-alkanedioic acid homologues were 16: 0 and 18: 1 (9) whereas 22: 0, 24: 0 and 26: 0, and 20: 0, 22: 0 and 24: 0 were usually the principal homologues in the 1-alkanol and alkanoic acid fractions, respectively. The most diagnostic feature of the suberins examined was the presence of monomers greater than C18 in chain length; most of the C16 and C18 monomers identified in the suberins also occur in plant cutins emphasizing the close chemical similarity between the two anatomical groups of lipid biopolymer.  相似文献   

6.
The component hydrocarbons, sterols, alcohols, monocarboxylic, α, ω-dicarboxylic and ω-hydroxy acids of the seagrasses Posidonia australis and Heterozostera tasmanica and a sample of P. australis detritus are reported. The fresh leaves of P. australis and P. australis detritus are characterized by a distinctive distribution of solvent-extractable long-chain monocarboxylic, α, ω-dicarboxylic and ω-hydroxy acids. This distinctive pattern should enable these lipid components along with other distinctive components to be used as chemical markers of the seagrass P. australis. H. tasmanica is characterized by (1) higher relative concentrations of 16:2ω6 and 16:3ω3 than P. australis, (2) the absence of the distinctive distribution pattern of long-chain monocarboxylic and ω-hydroxy acids observed for P. australis, (3) the absence of α, ω-diacids and (4) a lower absolute concentration of ω-hydroxy acids than P. australis.  相似文献   

7.
8.
9.
In this study we analysed three bacterial strains coded L10.10T, A4R1.5 and A4R1.12, isolated in the course of a study of quorum-quenching bacteria occurring in Antarctic soil. The 16S rRNA gene sequence was identical in the three strains and showed 99.7% pairwise similarity with respect to the closest related species Pseudomonas weihenstephanensis WS4993T. Therefore, the three strains were classified within the genus Pseudomonas. Analysis of housekeeping genes (rpoB, rpoD and gyrB) sequences showed similarities of 84-95% with respect to the closest related species of Pseudomonas, confirming its phylogenetic affiliation. The ANI values were less than 86% to the closest related species type strains. The respiratory quinone is Q9. The major fatty acids are C16:0, C16:1 ω7c/ C16:1 ω6c in summed feature 3 and C18:1 ω7c / C18:1 ω6c in summed feature 8. The strains are oxidase- and catalase-positive. Growth occurs at 4–30 °C, and at pH 4.0–10. The DNA G+C content is 58.2–58.3 mol %. The combined genotypic, phenotypic and chemotaxonomic data support the classification of strains L10.10T, A4R1.5 and A4R1.12 into a novel species of Pseudomonas, for which the name P. versuta sp. nov. is proposed. The type strain is L10.10T (LMG 29628T, DSM 101070T).  相似文献   

10.
Vibrio species are well known as motile, mostly oxidase-positive, facultative anaerobic Gram-negative bacteria. They are abundant in aquatic environments and are a common cause of human infections including diarrhea, soft tissue diseases, and bacteremia. Here, two Gram-negative bacteria, designated M12-1144T and M12-1181, were isolated from human clinical specimens and identified using a polyphasic taxonomic approach. Phylogenetic study based on 16S rRNA gene sequence analysis revealed that the isolates belong to the genus Vibrio, and are closely related to Vibrio metschnikovii KCTC 32284T (98.3%) and Vibrio cincinnatiensis KCTC 2733T (97.8%). The major fatty acids were summed feature 3 (C16:1 ω7c/C16:1 ω6c, 38.0%), C16:0 (23.0%), and summed feature 8 (C18:1 ω7c or C18:1 ω6c, 19.3%) and major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The G + C content of the genomic DNA was determined to be 44.1 mol%. DNA–DNA relatedness between the two newly isolated strains and V. metschnikovii KCTC 32284T and V. cincinnatiensis KCTC 2733T was between 42.6 to 47.5%. The similarities of genome-to-genome distance between M12-1144T and related species ranged from 18.4-54.8%. Based on these results, a new species of the genus Vibrio, Vibrio injenensis is proposed. The type strain is M12-1144 T(=KCTC 32233T =JCM 30011T).  相似文献   

11.
Umbilical veins (UV) and arteries (UA) of preeclamptic women in Curaçao harbor lower long-chain polyunsaturated fatty acids (LCP). The present aim was to test these findings in Mwanza (Tanzania), whose inhabitants have high LCPω3 and LCPω6 intakes from Lake Victoria fish. Women with preeclampsia (n=28) in Mwanza had lower PUFA and higher 20:0 in UV and UA, compared with normotensive/non-proteinuric controls (n=31). Their UV 22:6ω3, 22:4ω6, LCPω6, ω6, and LCPω3+ω6 were lower, while saturated FA, potentially de novo synthesized FA (Σde novo) and (Σde novo)/(LCPω3+ω6) ratio were higher. Their UA had higher 16:1ω7, ω7, 18:0, and 16:1ω7/16:0. Umbilical vessels in Mwanza had higher 22:6ω3, LCPω3, ω3, and 16:0, and lower 22:5ω6, 20:2ω6, 18:1ω9, and ω9, compared to those in Curaçao. Preeclampsia in both Mwanza and Curaçao is characterized by lower LCP and higher Σde novo. An explanation of this might be placental dysfunction, while the similarity of umbilical vessel FA-abnormalities in preeclamptic and diabetic pregnancies suggests insulin resistance as a common denominator.  相似文献   

12.
We have assessed that nuclear lipids from rat kidney cells are not only membrane components, but they are also found within the nucleus. The most abundant nuclear and endonuclear lipids have a high proportion of unsaturated fatty acids (n-6 series: arachidonic > linoleic), mainly esterified to PtdCho. Nuclear most abundant molecular species are 16:0–20:4, 16:0–18:2, 18:0–20:4, 18:0–18:2, and 16:0–18:1. Arachidonic acid is esterified at the sn-2 position of PtdCho: 16:0–20:4(25%), 18:0–20:4(15%), 18:2–20:4(3%), 18:1–20:4(2%). Exogenous [1-14C]20:4n-6-CoA is esterified in vitro in GP (glycerophospholipids) > > TAG and DAG. Five PtdCho molecular species were labeled: 16:0–20:4, 18:0–20:4, 18:1–20:4, 18:2–20:4, and 20:4–20:4. In conclusion, these results demonstrated that: (1) there is an important lipid pool within kidney cell nuclei; (2) main nuclear and endonuclear lipid pools were PtdCho molecular species which contained a high proportion of unsaturated fatty acids (20:4n-6 and 18:2n-6) esterified at sn-2 position and 16:0 esterified at sn-1 position; (3) kidney cell nuclei also contained the necessary enzymes to esterify exogenous 20:4n-6-CoA to glycerolipids and to GP; (4) exogenous 20:4n-6-CoA was esterified in five PtdCho molecular species with 20:4n-6 at the sn-2 position, although the most actively synthesized PtdCho contained 20:4n-6 at both the sn-1 and sn-2 positions of the molecule; (5) we can infer that by a remodeling process, the unsaturated fatty acids at the sn-1 position of PtdCho molecular species could be replaced by 16:0 and 18:0, and thus PtdCho would achieve the physiological profile characteristic of the organ.  相似文献   

13.
A novel Gram-negative, orange-pigmented bacterial strain JLT2008T was isolated from the surface seawater of the Western Pacific and subjected to a polyphasic taxonomic study. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain JLT2008T belonged to the genus Erythrobacter, sharing the highest similarity (96.6 %) with Erythrobacter gangjinensis K7-2T and the lowest similarity (94.9 %) with Erythrobacter litoralis DSM 8509T. Strain JLT2008T did not contain bacteriochlorophyll a, and the predominant respiratory lipoquinone was ubiquinone-10. The major fatty acids were C18:1 ω7c, C16:0, C16:1 ω7c/C16:1 ω6c. The prominent polar lipids were sphingoglycolipid, phosphatidylethanolamine, and phosphatidylglycerol. The genomic G + C content was 60.1 mol %. Based on the polyphasic taxonomic data, a novel species within the genus Erythrobacter, and with the name Erythrobacter westpacificensis sp. nov., is proposed. The type strain is JLT2008T (=CGMCC 1.10993T = JCM 18014T).  相似文献   

14.
This report deals with data on the cell ultrastructure of Candida tropicals strain D-2 mutants resistant to the polyene antibiotic, nystatin, and with an analysis of the fractional composition of neutral lipids and their fatty acids. The ultrastructural organization of the mutant cells is characterized by thickening of the cell wall and formation of invaginations into the cytoplasm, the appearance of new formations, large vacuoles, and reduction of the system of mitochondrial cristae. Lipids of nysr mutants differ from those of the nyss variant in having a decreased content of steroids and some fractions of neutral lipids. Certain nysr mutants manifest difference in the relative amounts of saturated and unsaturated fatty acids (C16:0, C16:1, C18:0, C18:1).  相似文献   

15.
The variety and distribution of phospholipids in the cell membranes of cultured cells and their fatty acid composition were analysed. Membranes of suspension cultured cells of Rauwolfia serpentina var. Bentham, Nicotiana tabacum var. Samsun, Atropa belladonna and Bouvardia ternifolia had almost the same composition of phosphatidylcholine, PC (ca 50%); phosphatidylethanolamine, PE (ca 25%); phosphatidylinositol, PI (ca 10%); phosphatidylglycerol, PG (several %); and phosphatidic acid, PA (several %). We determined the distribution of the molecular species of the three major phospholipid fractions (PC, PE and PI) in R.serpentina and N.tabacum. Membranes of both cell-types contained basically similar molecular species, 1–16:0/2–18:2 the main type, particularly in the PC- and PE- fractions; 1–18:2/2–18:2 and 1–18:0/2–18:2 for R. serpentina; and 1–16:0/2–18:3, 1-18:0/2-18:3 and 1-18:2/2-18:2 for N.tabacum. The influence of membrane fluidity on protoplast fusion as effected by the phase transition of the phospholipids, is discussed.  相似文献   

16.
This study was conducted to create a nutritional database on brown seaweeds and to popularize their consumption and utilization in Iran. The fatty acid contents, amino acids profiles, and certain mineral elements composition of some brown seaweeds, Padina pavonica (L.) Thivy, Dictyota dichotoma (Huds.) J. V. Lamour., and Colpomenia sinuosa (Mert. ex Roth) Derbés et Solier were determined. Total lipid content ranged from 1.46 ± 0.38 to 2.94 ± 0.94 g · 100 g?1dry weight (dwt), and the most abundant fatty acids were C16:0, C18:1, C20:4 ω6, and C20:5 ω3. The unsaturated fatty acids predominated in all species and had balanced sources of ω3 and ω6 acids. Highest total polyunsaturated fatty acid (PUFA) levels occurred in C. sinuosa. The protein content of D. dichotoma was 17.73 ± 0.29 g · 100 g?1dwt, significantly higher than the other seaweeds examined. Among amino acids essential to human nutrition, methionine (Met; in D. dichotoma and P. pavonica) and lysine (Lys; in C. sinuosa) were present in high concentrations. The crude fiber content varied by 9.5 ± 11.6 g · 100 g?1dwt in all species. Chemical analysis indicated that ash content was between 27.02 ± 0.6 and 39.28 ± 0.7 g · 100 g?1dwt, and that these seaweeds contained higher amounts of both macrominerals (7,308–9,160 mg · 100 g?1dwt; Na, K, Ca) and trace elements (263–1,594 mg · 100 g?1dwt; Fe, Ni, Mn, Cu, Co) than have been reported for edible land plants. C. sinuosa had the highest amount of Ca, Fe, and a considerable content of Na was measured in P. pavonica.  相似文献   

17.
18.
Four species of red marine algae (Rhodophyceae), five species of brown marine algae (Pheophyceae) and two species of green marine algae (Chlorophyceae) were examined for the fatty acid composition of the three lipid groups separated by silica gel column chromatography (neutral lipids, glycolipids, phospholipids). The four red algae had high contents of 16:0 and C20-polyunsaturated fatty acids (PUFA), 20:5n-3 ranging from 18 to 49% of the total fatty acid content and 20:4n-6 from 1.4 to 22.5%, these fatty acids were evenly distributed in all lipid groups. The five brown algae had high contents of 18:1n-9, 18:2n-6 and 18:3n-3 but low content of 20:5n-3. No precise trend was detected for the distribution of these fatty acids in the three lipid groups. The two green algae had high contents of 16:0, 18:1n-7 and 18:3n-3 and a very low content of PUFA. They contained also large amounts of 16:4n-3 together with 16:2n-6 and 16:3n-3. While 16:2n-6 was mainly found in phospholipids, 16:4n-3 was mainly distributed in neutral lipids and glycolipids.Porphyra umbilicalis represents the richest source of 20:5n-3 whileUndaria pinnatifida can be selected when a balanced mixture of (n-6) and (n-3) PUFA is required.Author for correspondence  相似文献   

19.
Plasmenyl phospholipids (1-alk-1′-enyl-2-acyl-3-glycerophospholipids, plasmalogens) are a structurally unique class of lipids that contain an α-unsaturated ether substituent at the sn-1 position of the glycerol backbone. Several studies have supported the hypothesis that plasmalogens may be antioxidant molecules that protect cells from oxidative stress. Because the molecular mechanisms responsible for the antioxidant properties of plasmenyl phospholipids are not fully understood, the oxidation of plasmalogens in natural mixtures of phospholipids was studied using electrospray tandem mass spectrometry. Glycerophosphoethanolamine (GPE) lipids from bovine brain were found to contain six major molecular species (16:0p/18:1-, 18:1p/18:1-, 18:0p/20:4-, 16:0p/20:4, 18:0a/20:4-, and 18:0a/22:6-GPE). Oxidation of GPE yielded lyso phospholipid products derived from plasmalogen species containing only monounsaturated sn-2 substituents and diacyl-GPE with oxidized polyunsaturated fatty acyl substituents at sn-2. The only plasmalogen species remaining intact following oxidation contained monounsaturated fatty acyl groups esterified at sn-2. The mechanism responsible for the rapid and specific destruction of plasmalogen GPE may likely involve unique reactivity imparted by a polyunsaturated fatty acyl group esterified at sn-2. This structural feature may play a central role determining the antioxidant properties ascribed to this class of phospholipids.  相似文献   

20.
Our previously published prostaglandin (PG) synthesis route, in which the ω-chain is added in the penultimate step, provides facile access to a wide variety of ω-chain variant PG analogs. Each series requires only the synthesis of the appropriate methylated acylphosphonate for the Emmons' condensation. The syntheses of analogs bearing the following methylation pattern are detailed: 15-Me; 17, 17-(Me)2; 17, 17, 20-(Me)3; 18, 18, 20-(Me)3; 15, 18, 18, 20-(Me)4; and 15-Ome-18, 18, 20-(Me)3. The well-known 16, 16-dimethyl prostaglandins have also been prepared by this sequence. The synthesis of 16, 16-tetramethylene-PG analogs is also described.  相似文献   

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