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1.
Katrina M. Nordström 《Archives of microbiology》1992,158(6):452-455
Two yellow and two red pigmented strains of Thermus were monitored for changes in fatty acid content and composition with reference to growth phase at the optimum temperature. Fatty acid content per mg of dry weight increased as the cultures aged. In addition the quantities of iso C 15:0, iso C 17:0 and iso C 16:0 increased in yellow pigmented strains, but in red pigmented strains, an increase was seen in iso C 15:0, but C 16:0 and iso C 16:0 levels decreased. Thus the fatty acid composition of these organisms varies with growth phase, and shows also strain specific variability. 相似文献
2.
The effect of copper supplementation on growth, methane monooxygenase activity and lipid composition of Methylococcus capsulatus (Bath) was studied. Copper increased biomass yield, methane monooxygenase activity and phospholipid content from 7.7 to 10.2% of dry weight. Cells from copper-deficient and copper supplemented cultures contained the same major fatty acids but in the presence of copper only the contents of C16:0 and the three C16:1 isomers were increased while the contents of C14:0 and cyclic C17:0 remained unchanged. Phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylglycerol and cardiolipin were analysed amongst the polar lipids. PE was the main component (about 60 mol-%) but the most notable copper-induced increment occurred in the proportion of PC, from about 10 to 16 mol-%. Concomitantly with this increment the fatty acids of PC were changed so that the mol-% of C16: 1 isomers were increased at the expense of other acids. Similar trends were seen also in the fatty acid compositions of other polar lipid fractions. It is therefore concluded that phosphatidylcholine would be one of the key factors when the role of membranous lipids in methane monooxygenase activity is to be considered. 相似文献
3.
Yaşar Durmaz Margarida Monteiro Narcisa Bandarra Şevket Gökpinar Oya Işik 《Journal of applied phycology》2007,19(3):223-227
Porphyridium cruentum was grown in 10 L batch culture at 18°C, pH 8.0 and 28‰ salinity. The cells were harvested in the stationary phase and the
fatty acid composition analysed by GC and tocopherol content by HPLC. A total of 14 fatty acids were identified including
saturated fatty acids (13:0, 14:0, 14:0 iso, 15:0, 16:0, 16:0iso) and monounsaturated fatty acids (MUFAs; 16:1(n-7), 18:1(n-7),
18:1(n-9). Polyunsaturated fatty acids (PUFAs) were the predominant fatty acids detected, reaching 43.7% of total fatty acids
in the stationary phase of culture. Among the PUFAs, eicosapentaenoic acid (EPA, 20:5(n-3)) was dominant (25.4%), followed
by 12.8% arachidonic acid (AA, 20:4(n-6)). α-Tocopherol and γ-tocopherol contents were 55.2 μg g−1 dry weight and 51.3 μg g−1 dry weight respectively. 相似文献
4.
D. E. Brown M. Hasan M. Lepe-Casillas A. J. Thornton 《Applied microbiology and biotechnology》1990,34(3):335-339
Summary The fungal micro-organism Trichoderma reesei was grown in batch culture with excess glucose at pH values between 2.7 and 4.5 and temperatures between 25°C and 35°C. A maximum lipid concentration of 16.9% of the cell dry weight was achieved at pH 3.2 and a temperature of 27°C. Lipid concentration was shown to be correlated with a calculated maximum specific growth rate (µ
mc
) and the maximum lipid value occurred at µ
mc
= 0.10 h–1. Fatty acid analysis was carried out and found to change with changing pH and temperature. Palmitic (16:0) acid and unusually high proportions of stearic acid (18:0) were commonly present. A conversion of fatty acids to palmitoleic acid (16:1) occurred following an unidentified nutrient limitation other than nitrogen depletion after 70 h of culture.
Offprint requests to: D. E. Brown 相似文献
5.
The lamellar membrane stacks of Ectothiorhodospira mobilis were isolated and purified by a combination of lysozyme and osmotic shock treatment, followed by differential and density gradient centrifugation. Preparations of lamellar membranes were enriched at least 2.4-fold in the ratio of bacteriochlorophyll a to protein.Thin-sectioning, negative staining, platinumcarbon shadowing and freeze-etching were used to study the architecture of the membrane units. Both platinum-carbon shadowing and freeze-etching showed the outer surfaces of the isolated lamellar membrane stacks to be relatively smooth. Particles averaging 7 nm in diameter were seen on several faces following freeze-ctching.Non-polar amino acids amounted to 60% of the total amino acid composition. Lipids constituted 32% of the membrane dry weight. Phosphatidyl ethanolamine and diphosphatidyl glycerol were the major phospholipids. Fatty acids of 10–15 carbons represented a small fraction of both membrane and whole cell fatty acids. Monoenes constituted 36% of the total membrane fatty acids and 38.4% of the total whole cell fatty acids. The major fatty acids of both whole cells and purified membranes were C16:0, C18:1 and cyclopropane C19:0. 相似文献
6.
Fatty acid elongation defective mutant was isolated from the ethyl methanesulfonate treated Hansenula polymorpha based on the growth ability. Using biochemical and genetic approaches, the mutant was characterized. When compared with the fatty acid phenotype of the parental strain, the differences in profile and content of fatty acids in V1 mutant were found. In this V1 mutant, polyunsaturated fatty acids, linoleic and alpha-linolenic acids, could not be detected with a corresponding increase in the content of mono-unsaturated fatty acids. The ratio of C16/C18 fatty acids revealed that the accumulation of C16 fatty acids was increased significantly. The experiments on fatty acid supplementation indicated that the mutant required C18:0 for the proper growth. The results of genetic complementation with the elongase genes of Saccharomyces cerevisiae confirmed that the lesion was occurred at least in the extension of C16:0 to C18:0 of V1. The H. polymorpha mutant obtained in this work will be used as a useful tool for unraveling the pathway of fatty acid synthesis and the role of fatty acids on biological processes. 相似文献
7.
Kenneth T. Hoppe Neil F. Hadley Richard N. Trelease 《Journal of insect physiology》1975,21(8):1427-1430
The dry weight of Spodoptera exigua eggs decreased by 15·9 μg/egg or 64% of initial weight during embryogenesis and development of pharate first instar larvae. Lipid depletion accounts for 36% of this total dry weight loss and this occurs at an essentially constant rate throughout development. This marks S. exigua as an exception since most insects utilize lipids more rapidly during later developmental stages. Lipid depletion is due primarily to triglyceride catabolism, although phospholipids also decrease significantly.Fatty acid composition remains stable during development. In triglycerides, 18:1 is most common followed by 16:0 and 18:2; in the phospholipids, the order of abundance is 18:1, 18:2, and 16:0. Egg fatty acids differ from dietary fatty acids: 16:1 comprises 7% of triglyceride fatty acids although it is not present in the larval media; 18:1 predominates in the egg whereas 18:2 is most abundant in the diet. 相似文献
8.
BIOCHEMICAL COMPOSITION AND FATTY ACID CONTENT OF FILAMENTOUS NITROGEN-FIXING CYANOBACTERIA 总被引:1,自引:0,他引:1
M. A. Vargas H. Rodríguez J. Moreno H. Olivares J. A. Del Campo J. Rivas M. G. Guerrero 《Journal of phycology》1998,34(5):812-817
The biochemical composition and fatty acid content of twelve strains of filamentous, heterocystous, nitrogen-fixing cyanobacteria have been determined. When grown under diazotrophic conditions, protein, carbohydrate, lipid, and nucleic acids comprised 37–52%, 16–38%, 8–13%, and 8–11% of the dry weight, respectively. The presence of a combined nitrogen source resulted in an increase in the protein content of the cells and a decrease in the levels of lipids and carbohydrates, although biomass productivity was not affected significantly. Biochemical composition also changed during culture growth, with the highest levels of proteins and lipids occurring as the culture entered stationary phase, whereas the highest levels of carbohydrate and nucleic acids were found during the exponential phase. Total fatty acid levels in the strains assayed ranged between 3 and 5.7% of the dry weight. With regard to fatty acid composition, all strains showed high levels of polyunsaturated fatty acids (PUFAs) and saturated fatty acids (SAFAs), with values of 24–45% and 31–52% of total fatty acids, respectively, whereas the levels of monounsaturated fatty acids (MUFAs) were in general lower (11– 32%). Palmitic acid (16:0) was the most prevalent SAFA, whereas palmitoleic (16:1n- 7) and oleic acid (18:1n-9) were the most abundant MUFAs in all the strains. Among PUFAs, γ-linolenic acid (GLA, 18:3n-6) was present at high levels (18% of total fatty acids) in Nostoc sp. (Chile) and at lower levels (3.6% of total fatty acids) in Anabaenopsis sp. The presence of GLA has not been previously reported in these genera of cyanobacteria. The rest of the strains exhibited high levels (12–35% of total fatty acids) of α-linolenic acid (ALA, 18:3n-3). Linoleic acid (18:2n-6) was also present at a substantial level in most of the strains. Eicosapentaenoic acid (EPA, 20:5n-3) was also detected in Nostoc sp. (Albufera). Some filamentous nitrogen-fixing cyanobacteria therefore represent potential sources of commercially interesting fatty acids. 相似文献
9.
Kirsi-Marja Oksman-Caldentey Nina Sevón Leena Vanhala Raimo Hiltunen 《Plant Cell, Tissue and Organ Culture》1994,38(2-3):263-272
Abatract The effect of carbon and nitrogen sources on two well-established hairy root clones, LBA1S and C58A, of Hyoscyamus muticus strain Cairo, were investigated. Both clones exhibited completely different patterns with regards to their growth rate, hyoscyamine accumulation, and fatty acid contents. Clone C58A grew faster and yielded more biomass (17.4 g l-1, in 21 days), but produced less hyoscyamine. The maximum hyoscyamine content (120 mg l-1) in clone LBA1S was reached in 28 days. Neither of the clones could use lactose or fructose as the sole carbon source, nor ammonium as the sole nitrogen source. The growth in the medium containing glucose was significantly reduced compared to that containing sucrose. Clone LBA1S was sensitive to the changes in sucrose concentration and an increase in ammonium in the culture medium, whereas C58A tolerated these changes better but was more sensitive to the increase in total nitrogen. Lipid synthesis was active in the exponential growth phase, and the total fatty acid content varied from 5 to 34 mg g-1 of dry root material. The major fatty acids were linoleic, palmitic and linolenic. There were considerable differences in the total amount of lipids and in their relative ratios when different nutrients were applied.Abbreviations DW
dry weight
- FA
fatty acids
- FFA
free fatty acids
- FW
fresh weight 相似文献
10.
Effects of temperature and nutritional changes on the fatty acids of agmenellum quadruplicatum. 总被引:2,自引:1,他引:1
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The fatty acid composition of the blue-green bacterium Agmenellum quadruplicatum was examined under a wide variety of growth conditions. The fatty acid composition was found to undergo significant changes with variations in temperature, media composition, and growth phase (log versus stationary). With increasing growth temperature (20 to 43 C) log-phase cells exhibited an increase in saturated fatty acids (38.4% at 20 C to 63.6% at 43 C). Striking changes were seen with some of the individual fatty acids such as 18.3, which made up 16.0% of the total fatty acid at 20 C but was not neasurable at 43 C. Fatty acid 12:0 was not measurable at 20 C but made up 16.3% of the total fatty acids at 43 C. Cell lipids were separated into neutral lipid, glycolipid, and very polar liquid fractions. The neutral lipid fraction was composed almost entirely of 12 carbon fatty acids (12:0, 12:1). Glycolipid and very polar lipids were more similar in their fatty acid composition when compared to the total cellular fatty acids, although they did lack 12 carbon fatty acids. The total of 12 carbon fatty acids in the cell can be used as an indicator of the amount of neutral lipid present. 相似文献
11.
浮游植物所含的不饱和脂肪酸是测定其作为食物质量的指标,并在浮游植物向浮游动物及其它动物能量转化过程中起着关键的作用,必需不饱和脂肪酸的缺乏有利于水华的形成。球形棕囊藻(Phaeocystis globosa)和铜绿微囊藻(Microcystis aeruginosa)分别是常见的海洋和淡水水华藻类,该文分析了它们在不同生长期的脂肪酸组成,探讨了这两种藻类的脂肪酸组成特征。球形棕囊藻和铜绿微囊藻的脂肪酸碳链长为14~20个碳原子,脂肪酸种类组成都比较简单,以饱和脂肪酸为主,未检测到二十碳五烯酸(Eicosapentaenoic acid,EPA)和二十二碳六烯酸 (Docosahexaenoic acid,DHA)等动物的必需脂肪酸。球形棕囊藻的总脂肪酸含量在247.294~735.44 μg·g-1干重之间,在对数期和延滞期含量最高的脂肪酸分别是C14:0和C16:0;而两株铜绿微囊藻的总脂肪酸在1 405.095~6 087.617μg·g-1干重之间,以C16:0含量最高。两株铜绿微囊藻的脂肪酸含量在对数期和延滞期差异明显(p<0.05),但球形棕囊藻的脂肪酸含量在不同生长期差别不大。由于缺乏必需脂肪酸EPA和DHA,球形棕囊藻和铜绿微囊藻不能为高营养级的生物提供必需的不饱和脂肪酸,不是浮游动物等生物的良好食物。因此球形棕囊藻和铜绿微囊藻作为浮游动物的食物质量较低,浮游动物对它们的捕食压力也较小,可能是这两种藻容易暴发水华的重要原因。 相似文献
12.
E. Eguchi Y. Ogawa K. Okamoto K. Mochizuki 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1994,164(2):94-102
Fatty acid compositions of the compound eyes of insects (soldier-bug, Hemiptera, and silk moth, Lepidoptera), crustaceans
(crayfish and grapsid crab, Decapoda) and inner and outer segments of visual cells of a squid (Cephalopoda, Mollusca) were
analyzed by gaschromatography for interspecific comparison. Fatty acid compositions showed great variation among species.
In insect compound eyes, 16:0 and 18:0 were the main saturated fatty acids, and 18:1 was the dominant unsaturated fatty acid.
Silk moth eyes contained, in addition, considerable amounts of 18:2 and 20:5. In crustacean compound eyes, the main saturated
fatty acids were 16:0 and 18:0, and 14:0 (5.0%) was only detected in grapsid crabs; the main unsaturated fatty acids were
20:4, 20:5 and 22:6. Both whole eyes and rhabdom fraction of crayfish showed similar profiles of fatty acid compositions.
Both inner and outer segments of squid retinae were characterized by high amounts of unsaturated fatty acids, especially 22:6.
Compound eyes of grapsid crabs were used for the experiments on seasonal changes of fatty acid compositions. UFA/SFA ratios
(weight in % of unsaturated fatty acids saturated fatty acids) were lowest (1.0) in July and highest (2.5) in March, and unsaturation
indexes (average number of double bonds per molecule) were lowest (1.5) in July and highest (2.3) in March. Fatty acids 18:0
and 20:1 showed a significant correlation with the changes of seasonal temperature. Fatty acid analysis of the developing
compound eyes of silk moths during the pupal stage revealed that eicosapentanoic acid (20:5) increased remarkably in parallel
with the development of photoreceptive membranes, the rhabdoms. This suggests that eicosapentaenoic acid may play an important
role in formation and function of rhabdoms. 相似文献
13.
The algal class Chlorarachniophyceae is comprised of a small group of unicellular eukaryotic algae that are often characterized by an unusual amoeboid morphology. This morphology is hypothesized to be the result of a secondary endosymbiosis in which a green alga was engulfed as prey by a nonphotosynthetic amoeba or amoebaflagellate. Whereas much is known about the phylogenetic relationships of individual chlorarachniophytes to one another, and to possible ancestral host organisms in the genera Cercomonas and Heteromita, little is known about their physiology, particularly that of their lipids. In an initial effort to characterize the lipids of this algal class, seven organisms were examined for their fatty acid and sterol composition. These included Bigelowiella natans, Chlorarachnion globusum, Chlorarachnion reptans, Gymnochlora stellata, Lotharella amoeboformis, Lotharella globosa, and Lotharella sp. Fatty acids associated with chloroplast‐associated glycolipids, cytoplasmic membrane‐associated phospholipids, and storage triglycerides were characterized. Glycolipid fatty acids were found to be of limited composition, containing principally eicosapentaenoic acid [20:5(n‐3)] and hexadecanoic acid (16:0), which ranged in relative percentage from 67–90% and 10–29%, respectively, in these seven organisms. Triglyceride‐associated fatty acids were found to be similar. Phospholipid fatty acid composition was more variable. The principal phospholipid fatty acids, 16:0 (25–32%) and a compound tentatively identified as docosapentaenoic acid [22:5(n‐3)] (26–35%), were found along with a number of C18 and C20 fatty acids. All organisms contained two sterols as free sterols. These were tentatively identified as 24‐ethylcholesta‐5,22E‐dien‐3b‐ol (stigmasterol; 70–95%) and 24‐methylcholesta‐5,22E‐dien‐3b‐ol (brassicasterol; 5–30%). 相似文献
14.
R. Blasig W. -H. Schunck W. Jockisch P. Franke H. -G. Müller 《Applied microbiology and biotechnology》1984,19(4):241-246
Summary Cells of the yeast Lodderomyces elongisporus, precultured on glycerol, were incubated with long-chain n-alkanes. The results whow that monoterminal alkane oxidation is the main pathway of alkane degradation in the investigated yeast. The amount of diterminal activity is negligible, while subterminal degradation did not occur at all.Fatty acids were the first detectable intermediates. Using different n-alkanes, in every case the fatty acids with substrate chain length predominated in the cells. The formation of radioactive fatty acids from (1-14C)-hexadecane was time-dependent and indicated that desaturation elongation and -oxidation occurred.Extracellularly, the fatty acid pattern was similar, except for the additional presence of fatty acid methyl esters and the prevalence of octadecenoic acid after growth of cells on n-hexadecane. 相似文献
15.
Differences between clones of the diatom Cylindrotheca fusiformi were studied with respect to growth rate, total lipid content and fatty acid composition. Sixty clones were isolated and cultivated under batch conditions. All clones were grown under identical conditions (temperature 22±1°C, light intensity 100 μmol photon m−2 s−1, salinity 28, F/2 medium) and were harvested in the late exponential growth phase for lipid and fatty acid analysis. The results show a wide variation in growth, total lipid content and fatty acid profiles among clones (p<0.05). The major fatty acids in the 60 clones were 14:0 (4.6–9.1%), 16:0 (18.2–32.0%), 16:1n-7 (21.6–33.1%), 20:4n-6 (4.1–13.5%) and 20:5n-3 (6.2–17.2%), with the highest proportion of 20:4n-6 in clone CF13 (13.5%), and the highest proportion of 20:5n-3 in clone CF5 (17.2%). The results support the view that some microalgal fatty acid variation is not restricted to interspecific variation and external factors, but also varies from clone to clone within the same species. 相似文献
16.
Ilka Duldhardt Julia Gaebel Lukasz Chrzanowski Ivonne Nijenhuis Claus Härtig Frieder Schauer Hermann J. Heipieper 《Microbial biotechnology》2010,3(2):201-209
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. 相似文献
17.
Presence of methyl branched fatty acids and saturated hydrocarbons in botryococcene producing strain of Botryococcus braunii 总被引:1,自引:0,他引:1
C. Dayananda R. Sarada P. Srinivas T. R. Shamala G. A. Ravishankar 《Acta Physiologiae Plantarum》2006,28(3):251-256
Botryococcus braunii (N-836) produced 60 – 73% hydrocarbons on dry weight basis, of which C34 botryococcene was found to be the major hydrocarbon, constituting about 50 – 76 % of total content throughout the experimental
studies. Major fatty acids present in this organism were C18:1 and C16:0. Saturated hydrocarbons like docosane, hexacosane
and heptacosane were also found to be produced by the organism. Methyl branched fatty acids, were identified as 16-methyl
heptadecanoic and 5, 9, 13 - trimethyl tetradecanoic acids by GC-MS. Maximum hydrocarbon accumulation was observed during
third week of its growth. 相似文献
18.
Minna K. Virtala Katrina M. Nordström Matti T. Karp Simo V. Laakso 《Archives of microbiology》1993,160(1):12-17
Elimination of plasmids from Thermus flavus, T. thermophilus and three wild Thermus strains caused alterations in growth temperature range, pigmentation and membrane fatty acids without affecting viability. Following plasmid elimination all Thermus strains lost their ability to grow above 70°C. In addition, the minimum growth temperature was lowered by 5–10°C. Fatty acids were reduced by an average of approximately 35%. In addition, the contribution of iso- and anteisobranched fatty acids were altered in four of the five strains. The iso C15:0/iso C17:0 ratio approached 1.0 in all strains, whereas the anteiso C15:0/anteiso C17:0 was reduced to 0.2. The iso C16:0/normal-C16:0 ratio increased in all strains due to an increase in iso C16:0 in four strains and a reduction in normal-C16:0 relative to iso C16:0 in one strain. However, it was evident that the plasmid-free strains were able to compensate for these alterations in membrane fluidity to a certain extent by reducing the average chain length of isobranched acids. Altered fatty acid metabolism at the level of precursors may have influenced membrane composition and consequently growth temperature range. 相似文献
19.
海、淡水驯化对5种微藻脂肪酸组成的影响 总被引:4,自引:1,他引:4
对5种微藻进行了脂肪酸分析及海淡水驯化影响其脂肪酸组成的研究,结果表明:谈水小球藻和海水小球藻的特征脂肪酸均为16:0、16:2、18:0、18:2和18:3;淡水斜生栅藻的特征脂肪酸为16:0、18:1和18:3;海水三角褐指藻的特征脂肪酸为14:0、16:0、16:1和EPA。淡水藻海水驯化和海水藻淡水驯化后,特征脂肪酸的种类不发生变化,但各种脂肪酸的含量有明显变化,驯化后,几种特征脂肪酸及总脂肪酸占细胞干重的比例在蛋白核小球藻、小球藻-1和三角褐指藻SS02品系中均有不同程度的提高,而在斜生栅藻、小球藻-2和三角褐指藻ZS08、XSO3品系中均有不同程度的下降。 相似文献
20.
《Biochimica et Biophysica Acta (BBA)/Lipids and Lipid Metabolism》1982,710(3):485-492
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 C16:0, C16:1, C16:1, C16:0, C18:0, C18:1, C18:2 and C18:3 fatty acids were detected. The hexadecenoic acid was shown to be 9-C16:1 while the octadecenoic acid was a mixture of 93% 11-C18:1 and 7% 9-C18:1. The fatty acid content increased during the first 4 days of growth and then decreased slightly. 相似文献