Lipid and Fatty Acid composition of chloroplast envelope membranes from species with differing net photosynthesis

Lipid and fatty acid compositions were determined for chloroplast envelope membranes isolated from spinach (Spinacia oleracea L.), sunflower (Helianthus annuus L.), and maize (Zea mays L.) leaves. The lipid composition was similar in sunflower, spinach, and undifferentiated maize chloroplast envelope membranes and different in maize mesophyll chloroplast envelope membranes. The predominant lipid constituents in all envelope membranes were monogalactosyldiglyceride (27 to 46%), digalactosyldiglyceride (18 to 33%), and phosphatidylcholine (7 to 30%). The fatty acid composition was also similar in sunflower and spinach chloroplast envelope membranes in comparison to those from maize. The major acyl fatty acids of the chloroplast envelope membrane were palmitic (C_16:0, 41 and 36%) and linolenic (C_18:3, 29 and 40%) acids for spinach and sunflower; palmitic (77%) and stearic (C_18:0, 12%) acids for young maize; and palmitic (61%), stearic (14%), and linolenic (13%) acids for mature maize. The differences in lipid and acyl fatty acid compositions among these plants which vary in their rates of net photosynthesis were largely quantitative rather than qualitative.     

Leishmania species: fatty acid composition of promastigotes

The fatty acid composition of the total lipid fractions of five different Leishmania organisms grown on Eagle's medium was determined by gas chromatography. The major fatty acids identified in the total lipid fractions of L. donovani, L. tropica major, L. tropica minor, L. tropica (England strain), and L. enriettii were C_12:0, C_13:0, C_14:0, C_15:0, C_16:0, C_17:0, C_18:0, C_18:1, C_18:2, and C_18:3. The statistical differences among the fatty acid methyl esters of different Leishmania organisms are discussed.Gas chromatographic analysis of the fatty acid methyl esters of the total lipid fractions of the original Eagle's medium and the media after harvesting of various Leishmania species revealed the presence of C_18:3 fatty acid in the total lipid fraction of the medium of L. donovani and the complete absence of 18-carbon unsaturated fatty acids in the total lipid fraction of the medium of L. enriettii. The use of such differences in the differentiation of various Leishmania species is discussed.     

Effects of sodium chloride concentration on phospholipid fatty acid composition of yeasts differing in osmotolerance

The effect of growth medium NaCl concentration on the fatty acid composition of phospholipids of 3 strains of Saccharomyces cerevisiae and 6 osmotolerant yeast strains was examined. The S. cerevisiae strains were characterized by a high content of palmitoleic (C_16:1) acid and by having no polyunsaturated C₁₈ acids, whereas the osmotolerant strains had a low content of C_16:1 and a high proportion of polyenoic C₁₈ acids. An increase of the NaCl concentration from 0% to 8% resulted in a decrease of the cellular phospholipid content on a dry-weight basis, for all strains but one of the osmotolerant strains. For the S. cerevisiae strains increased salinity produced a slight decrease of the proportion of C₁₆ fatty acids with a concomitant increase of C₁₈ acids, whereas the osmotolerant strains showed an increase of the relative content of oleic acid (C_18:1) at the expense of the proportion of polyenoic C₁₈ acids.     

Complex lipids of Rhodomicrobium vannielii

Eight components, seven of which contained phosphorus, were found in the phospholipid fraction of Rhodomicrobium vannielii. The major components were lipoamino acid (o-ornithine ester of phosphatidyl glycerol, 46.5%) and phosphatidyl choline (26.5%). The other six components were phosphatidyl glycerol (9.7%), bisphosphatidic acid (6.7%), phosphatidyl ethanolamine (4.5%), phosphatidic acid (1.8%), lysophosphatidyl glycerol-o-ornithine ester (3.2%), and N,N-ornithine amide of unidentified fatty acid (0.95%). Total phospholipid accounted for 4.2% of cell dry weight. The major fatty acid was vaccenic acid, C_18:1, which accounted for approximately 90% of the total fatty acids of the complex lipid fraction. The other four fatty acids were C_16:0 (6.25%), C_18:0 (3.8%), C_14:0 (0.7%), and C_16:1 (0.35%). The sulfolipid content was 0.01% of the cell dry weight or 0.14 μmoles per g of dried cells, assuming that its fatty acid component is vaccenic acid. No steroids were detected.     

Effect of Growth Temperature on Fatty Acid Composition of Ten Thermus Strains

The fatty acid composition of Thermus spp., including T. aquaticus ATCC 25104, T. thermophilus DSM 579, T. flavus DSM 674, and seven wild strains was examined. Organisms were tested at a minimum of either 35, 40, or 45°C and at an optimum of 60 or 70°C. Total fatty acid content per dry weight of cells varied between 1.2 and 3.7%, and the quantity of fatty acids was higher at the high temperature range in the majority of strains. At the optimum temperature, strains could be assigned to three chemotaxonomic groups with reference to the ratio of iso C_15:0/iso C_17:0. In six of the strains the ratio of iso C_15:0/iso C_17:0 remained unchanged at the minimum temperature, whereas in four strains the ratio was reversed. The proportion of the C_15:0 and C_17:0 isobranched acids was decreased and the proportion of anteisobranched fatty acids, namely anteiso C_15:0, anteiso C_17:0, and anteiso C_17:1, was increased at the lower temperature range. Some changes were seen in the levels of the n-C_16:0 and iso C_16:0 acids, but these were strain specific.     

Substrate specificity of acyl-lipid Δ9-desaturase from <Emphasis Type="Italic">Prochlorothrix hollandica</Emphasis> cyanobacterium producing myristoleic acid

Chlorophyll b-containing cyanobacterium Prochlorothrix hollandica is characterized by a high content of esterified fatty acids (FA) with 14 and 16 carbon atoms in the membrane lipids. Depending on the conditions of cultivation, the relative amount of myristic (C_14:0) and myristoleic (C_14:1) acids can reach 35%, and palmitic (С_16:0) and palmitoleic (С_16:1) acids can reach 60% of the sum of all fatty acids in cells. Monounsaturated FAs are represented by C_14:1, and C_16:1 with an olefinic bond presumably located in the Δ⁹ position. We cloned the gene of acyl-lipid Δ9-desaturase, desC1, from Prochlorothrix hollandica and characterized its specificity to the length of the substrate using the heterologous expression in Escherichia coli cells adding C_14:0 or stearic (C_18:0) acids as exogenous substrates. The results show that DesC1 Δ⁹ desaturase generates olefinic bonds in the FAs with a length of 14 to 18 carbon atoms with an approximately equal efficiency. This indicates that the length of the FA chain in P. hollandica is determined by the activity of the FA synthase, and the chain is desaturated at the Δ⁹ position nonspecifically relatively to its length.     

Studies on monoacylglycerols from Gordona lentifragmenta,Gordona bronchialis and Gordona rubropertincta

Monoacylglycerols containing α-branched-β-hydroxylated fatty acids (mycolic acids) ranging from C₄₂ to C₅₀ and from C₆₀ to C₆₆, were isolated from Gordona lentifragmenta and from G. bronchialis, respectively. On the other hand, G. rubropertincta showed only a monoacylglycerol fraction which released non-hydroxylated fatty acids; they were identified as C_16:0-, C_16:1,- C_18:1- and branched C_19:0-fatty acids. This last component was identified as 10-methyl octadecanoic acid (tuberculostearic acid).     

Effect of Temperature on Fatty Acid Composition of a White Thermus Strain

A white Thermus sp. strain, NCIMB 11245, showed high levels of anteiso C_17:0, anteiso C_17:1, normal C_16:1, and iso C_16:0 with low levels of iso C_15:0 + iso C_17:0 in comparison to yellow-pigmented strains. The fatty acid composition may be associated with precursor metabolism or the absence of carotene pigmentation.     

Structure and composition of hydrocarbons and fatty acids from a marine blue-green alga,Synechococcus sp.

The major hydrocarbons of Synechococcus sp., a marine blue-green alga isolated from the Gulf of Mexico, were identified as 1-nonadecene and 1,14-nonadecadiene. The content of 1-nonadecene increased with culture age from about 0.5 mg/g dry weight in young cells to about 2.3 mg/g dry weight in old cells, while the content of 1,14-nonadecadiene remained constant with culture age at about 1 mg/g dry weight. Both [1-¹⁴C]acetate and [2-¹⁴C]acetate were incorporated to equal extents into the hydrocarbons. [1-¹⁴C]Stearate was incorporated into the hydrocarbons, but [³H]arachidate was not. The fatty acids of Synechococcus sp. were typical of blue-green algae, consisting of C_16:0, C_16:1, C_16:1, C_16:0, C_18:0, C_18:1, C_18:2 and C_18:3 fatty acids were detected. The hexadecenoic acid was shown to be 9-C_16:1 while the octadecenoic acid was a mixture of 93% 11-C_18:1 and 7% 9-C_18:1. The fatty acid content increased during the first 4 days of growth and then decreased slightly.     

Effects of insect cuticular fatty acids on in vitro growth and pathogenicity of the entomopathogenic fungus Conidiobolus coronatus

Eighteen fatty acids identified in the cuticle of three insect species representing differing susceptibilities to C. coronatus infection, were tested for effects on the in vitro growth and pathogenicity of the parasitic fungus. At all applied concentrations (0.1-0.0001% w/v) growth was inhibited by C_16:0, C_16:1, C_18:0, C_18:1, C_18:2, C_18:3, C_20:0 and C_20:1. At high concentrations spore germination was inhibited by C_7:0, C_8:0, C_9:0, C_10:0, C_12:0, C_18:2 and C_18:3 and hyphal growth was merely retarded by C_5:0, C_6:0, C_6:2, C_14:0, C_16:0, C_16:1, C_18:0, C_18:1, C_20:0 and C_20:1. The presence of C_15:0 at the 0.1% concentration stimulated growth of C. coronatus. Sporulation was inhibited by all concentrations of C_16:0 and C_18-20 fatty acids. Low concentrations of C_5:0, C_6:0, C_6:2 and C_7:0 enhanced sporulation. Fatty acids C_5-12 as well as C_18:3, C_20:0 and C_20:1 decreased the ability of fungal colonies to infect G. mellonella while C_16:1 elevated it thus suggesting that C_16:1 may stimulate production of enzymes involved in the host invasion. Toxicity of metabolites released into incubation medium decreased with varying degrees in the presence of C_6:0, C_6:2, C_7:0, C_9:0, C_12:0, C_16:1, C_18:2, C_18:3, C_20:0 and C_20:1; other fatty acids had no effect. Further work is needed to analyse the effects of exogenous fatty acids on the C. coronatus enzymes implicated in fungal pathogenicity as well as on the production of insecticidal metabolites.     

Some variations in the composition of suberin from the cork layers of higher plants

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.     

Fat Metabolism in Higher Plants XXXVI: Long Chain Fatty Acid Synthesis in Germinating Peas

A low lipid, high starch containing tissue, namely cotyledons of germinating pea seedlings was examined for its capacity to synthesize fatty acid. Intact tissue slices readily incorporate acetate-¹⁴C into fatty acids from C₁₆ to C₂₄. Although crude homogenates synthesize primarily 16:0 and 18:0 from malonyl CoA, subsequent fractionation into a 10,000g pellet, a 10⁵g pellet and supernatant (soluble synthetase) revealed that the 10⁵g pellet readily synthesizes C₁₆ to C₂₈ fatty acids whereas the 10,000g and the supernatant synthesize primarily C₁₆ and C₁₈. All systems require acyl carrier protein (ACP), TPNH, DPNH if malonyl CoA is the substrate and ACP, Mg²⁺, CO₂, ATP, TPNH, and DPNH if acetyl CoA is the substrate. The cotyledons of germinating pea seedlings appear to have a soluble synthetase and 10,000g particles for the synthesis of C₁₆ and C₁₈ fatty acid, and 10⁵g particles which specifically synthesize the very long chain fatty acid from malonyl CoA, presumably via malonyl ACP.     

Phospholipid fatty acid ester composition ofPasteurella multocida andActinobacillus lignieresii

Cell surface hydrophobicity properties vary dramatically, whereas cell envelope phospholipid composition is essentially identical among strains ofPasteurella multocida andActinobacillus lignieresii. Fatty acid ester composition of the major phospholipid fractions from cell surface hydrophobicity variants was examined to determine whether hydrophobic properties are influenced by cell envelope fatty acid content. Individual phospholipids were resolved by preparative thin-layer chromatography, and methanolysis was performed with boron trifluoride-methanol. Gas-liquid chromatographic analysis revealed the organisms to be similar qualitatively, whereas hydrophobic variants exhibited consistently, greater and more disparate C_16:0+C_16:1/C_14:0 ratios in all fractions. Fatty acid composition of phospholipids may be related to surface hydrophobicity properties ofP. multocida variants. However, comparative data obtained forA. lignieresii revealed a degree of similarity withP. multocida that precludes use of this parameter as a means for differentiation of thesePasteurellaceae type species, thereby supporting their taxonomic relatedness.     

Photobacterium marinum sp. nov., a marine bacterium isolated from a sediment sample from Palk Bay,India

The novel, cream colored, Gram-staining-negative, rod-shaped, motile bacteria, designated strains AK15^T and AK18, were isolated from sediment samples collected from Palk Bay, India. Both strains were positive for arginine dihydrolase, lysine decarboxylase, oxidase, nitrate reduction and methyl red test. The major fatty acids were C_16:0, C_{18:1 ω7c}, C_{16:1 ω7c} and/or C_{16:1 ω6c} and/or iso-C_15:0 2-OH (summed feature 3). Polar lipids content of strains AK15^T and AK18 were found to bephosphatidylethanolamine (PE), two unidentified phospholipids (PL1 and PL2) and three unidentified lipids (L1-L3). The 16S rRNA gene sequence analysis indicated strains AK15^T and AK18 as the members of the genus Photobacterium and closely related to the type strain Photobacterium jeanii with pair-wise sequence similarity of 96.7%. DNA–DNA hybridization between strain AK15^T and AK18 showed a relatedness of 87%. Based on data from the current polyphasic study, strains AK15^T and AK18 are proposed as novel species of the genus Photobacterium, for which the name Photobacterium marinum sp. nov. is proposed. The type strain of Photobacterium marinum is AK15^T (=MTCC 11066^T = DSM 25368^T).     

Characterization of two novel pentose-fermenting and GABA-producing species: Levilactobacillus tujiorum sp. nov. and Secundilactobacillus angelensis sp. nov. Isolated from a solid-state fermented zha-chili

Lactobacilli are dominant in zha-chili. This study provides a taxonomic characterization of five bacterial strains isolated from zha-chili in China. The cells were Gram-positive, facultative anaerobic, non-spore-forming, flagella-free, catalase-negative, heterofermentative, pentose-fermenting, and gamma-aminobutyric acid (GABA)-producing rods. For HBUAS51241^T, HBUAS51329, and HBUAS51416, C_16:0, C_18:1 ω9c and C_19:0 iso were the predominant cellular fatty acids; diphosphatidylglycerol (DPG), phosphatidylglycerol (DP), glycolipids (GL), and glycolipids (AL) were the major phospholipids. While for HBUAS51383^T and HBUAS58055, C_16:0, C_18:1 ω9c, C_19:0 cyclo ω8c were the predominant cellular fatty acids; DPG, DP, GL, and AL were the major phospholipids. Strains HBUAS51241^T, HBUAS51329, and HBUAS51416 showed 98.1–99.1% 16S rRNA gene sequence similarity, 80.2–81.4% ANI, 87.7–90.0% AAI, and 23.8–32.8% digital DDH to their closest related type strains Levilactobacillus hammesii DSM 16381^T, Levilactobacillus parabrevis ATCC 53295^T, and Levilactobacillus fuyuanensis 244-4^T. Strains HBUAS51383^T and HBUAS58055 showed 98.7–99.5% 16S rRNA gene sequence similarity, 75.4–81.4% ANI, 75.5–89.1% AAI, and 19.7–24.0% digital DDH to their closest related type strains Secundilactobacillus silagincola IWT5^T, Secundilactobacillus silagei JCM 19001^T, Secundilactobacillus pentosiphilus IWT25^T, Secundilactobacillus mixtipabuli IWT30^T, Secundilactobacillus odoratitofui DSM 19909^T, and Secundilactobacillus similis DSM 23365^T. The central carbon metabolism pathways for the five strains were summarizeded. Based on the phenotypic, chemotaxonomic, and genomic data, we propose two novel species Levilactobacillus tujiorum sp. nov. whose type strain is HBUAS51241^T (=GDMCC 1.3022^T = JCM 35241^T), and Secundilactobacillus angelensis sp. nov. whose type strain is HBUAS51383^T (=GDMCC 1.3021^T = JCM 35209^T).     

Lipid and Fatty Acid Composition in the Flesh of an Edible Marine Fish: Amadi (Coilia reynaldi)

Amadi is a small sized edible marine fish species (Coilia reynaldi) under the order-Clupeiformes. It is important for principal lipids and in particular for highly unsaturated fatty acids which have potential biomedical benefits. Among the lipid classes, phospholipids were found to be the most predominant constituents than the glycolipid and neutral lipid in Amadi. Twenty six fatty acids were quantified by open tube gas–liquid chromatography. Dominant fatty acids in this fish are Palmitic acid (C_16:0), Stearic acid (C_18:0), Oleic acid (C_18:1n?9), Myristic acid (C_14:0), Palmitoleic acid (C_16:1), Docosahexanoic acid (C_22:6n?3), Pentadecanoic acid (C_15:0), and Eicosatetraenoic acid (C_20:4n?3). Fatty acid deficiency in fish species is indicated by the presence of C_20:3n?9 acid. It is absent in this fish.The content of DHA and EPA are maximum in amount in neutral lipid than other lipid classes.     

Adaptation of anaerobically grown Thauera aromatica,Geobacter sulfurreducens and Desulfococcus multivorans to organic solvents on the level of membrane fatty acid composition

The effect of different solvents and pollutants on the cellular fatty acid composition of three bacterial strains: Thauera aromatica, Geobacter sulfurreducens and Desulfococcus multivorans, representatives of diverse predominant anaerobic metabolisms was investigated. As the prevailing adaptive mechanism in cells of T. aromatica and G. sulfurreducens whose cellular fatty acids patterns were dominated by palmitic acid (C16:0) and palmitoleic acid (C16:1cis), the cells reacted by an increase in the degree of saturation of their membrane fatty acids when grown in the presence of sublethal concentrations of the chemicals. Next to palmitic acid C16:0, the fatty acid pattern of D. multivorans was dominated by anteiso-branched fatty acids which are characteristic for several sulfate-reducing bacteria. The cells responded to the solvents with an increase in the ratio of straight-chain saturated (C14:0, C16:0, C18:0) to anteiso-branched fatty acids (C15:0anteiso, C17:0anteiso, C17:1anteisoΔ9cis). The results show that anaerobic bacteria react with similar mechanisms like aerobic bacteria in order to adapt their membrane to toxic organic solvents. The observed adaptive modifications on the level of membrane fatty acid composition can only be carried out with de novo synthesis of the fatty acids which is strictly related to cell growth. As the growth rates of anaerobic bacteria are generally much lower than in the so far investigated aerobic bacteria, this adaptive response needs more time in anaerobic bacteria. This might be one explanation for the previously observed higher sensitivity of anaerobic bacteria when compared with aerobic ones.     

Changes in Cellular Fatty Acid Composition of Cephalosporium acremonium during Cephalosporin C Production

Cephalosporium acremonium was cultivated in fermentation medium containing sucrose or methyl oleate as a carbon source for cephalosporin C production. The level of antibiotic production was 48 g of cephalosporin C per liter under optimum conditions when methyl oleate was used. The C_18:1 (oleic acid) methyl ester appeared to be utilized faster than the C_18:2 (linoleic acid) methyl ester in fermentation broth. Physiological characteristics of C. acremonium were investigated by determining the fatty acid composition of the total cellular free lipid. Significant changes in cellular fatty acid composition occurred during inoculum cultivation and fermentation. The percentage of C_18:1 increased from 19.1 to 38.5%, but the percentage of C_18:2 decreased from 56.7 to 36.1%, and there was an increase in pH during inoculum cultivation. The cellular fatty acid composition of C. acremonium grown in fermentation medium containing methyl oleate (methyl oleate medium) was significantly different from that in fermentation medium containing sucrose (sucrose medium). The major fatty acids detected were C_16:0 (palmitic acid), C_18:1, and C_18:2. In methyl oleate medium, the ratio of C_18:1 to C_18:2 increased from 0.34 to 1.37, while the cell morphology changed from hyphae to arthrospores and conidia. In contrast, in sucrose medium, the ratio of C_18:1 to C_18:2 decreased from 0.70 to 0.43, and most of the cells remained hyphal at the end of fermentation. We observed that hyphae contained a higher proportion of C_18:2 but arthrospores and conidia contained a higher proportion of C_18:1.