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1.
The structure of liquid hydrocarbons and fatty acids produced by the green alga Botryococcus was identified. Two representatives of this alga, Botryococcus braunii Kütz, strain IPPAS H-252, introduced into culture earlier and an organism isolated for the first time from the Shira Lake, were used for this identification. Fatty acid composition of B. braunii, strain H-252, lipids was characterized by a high content of trienoic acids of C16–C18 series. The hydrocarbon composition of this strain was represented by straight-chain and branched-chain C14–C28 components; long-chain linear aliphatic C20–C27 hydrocarbons (54.4%) and 2,6,10,14-tetramethylhexadecane (20.5%) predominated among them. The strain H-252 differed in its fatty acid and hydrocarbon composition from the strains described earlier as Botryococcus braunii. The fatty acid composition of the Botryococcus isolate was represented mainly by C12–C32 saturated and monoenoic acids. The hydrocarbons formed by this isolate were represented by dienoic and trienoic components. C29 (48.9–56.3%) and C31 (11.1–16.3%) hydrocarbons predominated among the C23–C31 dienoic hydrocarbons, and C27, C29, and C31 trienoic hydrocarbons comprised 2.5–2.6% of total hydrocarbons. This type of hydrocarbons and the lipid fatty acid composition were characteristic for the race A of B. braunii.  相似文献   

2.
The fatty-acid composition of microbial cells in 17 pathogenic and saprophytic Leptospira strains, comprising 14 serovars and 10 serogroups, has been studied. The strains under investigation have proved to fall into 3 groups differing by this characteristic. The group of saprophytic strains is characterized by a comparatively high level of myristic acid and, consequently, by the ratio of saturated and unsaturated fatty acids with 14 carbon atoms approaching 1:1; besides, it is also characterized by a lower, in comparison with the pathogenic Leptospira strains belonging to the serogroups Icterohaemorrhagiae, Canicola, Ballum has a higher level of unsaturated fatty acids. The second group of pathogenic Leptospira strains including the serogroups Grippotyphosa, Hebdomadis, Pomona, Tarassovi, Pyrogenes, Australia has been found to occupy an intermediate position between the first group of pathogenic Leptospira strains and the group of saprophytic ones. As the difference in the content of myristic acid in pathogenic and saprophytic Leptospira strains is a stable characteristic, it can be used for the differentiation of these strains. The present investigation has revealed that the distribution of the main fatty acids in Leptospira phospholipids is similar to their distribution in Leptospira neutral lipids with the exception of unsaturated fatty acid with 14 carbon atoms, occurring mainly in phospholipids.  相似文献   

3.
Five Lactobacillus strains of intestinal and food origins were grown in MRS broth or milk containing various concentrations of linoleic acid or conjugated linoleic acid (CLA). The fatty acids had bacteriostatic, bacteriocidal, or no effect depending on bacterial strain, fatty acid concentration, fatty acid type, and growth medium. Both fatty acids displayed dose-dependent inhibition. All strains were inhibited to a greater extent by the fatty acids in broth than in milk. The CLA isomer mixture was less inhibitory than linoleic acid. Lactobacillus reuteri ATCC 55739, a strain capable of isomerizing linoleic acid to CLA, was the most inhibited strain by the presence of linoleic acid in broth or milk. In contrast, a member of the same species, L. reuteri ATCC 23272, was the least inhibited strain by linoleic acid and CLA. All strains increased membrane linoleic acid or CLA levels when grown with exogenous fatty acid. Lactobacillus reuteri ATCC 55739 had substantial CLA in the membrane when the growth medium was supplemented with linoleic acid. No association between level of fatty acid incorporation into the membrane and inhibition by that fatty acid was observed.  相似文献   

4.
Abstract The cellular long-chain fatty acids of 32 strains representing 10 species of the genus Kluyveromyces were extracted by saponification and analyzed as methyl esters by gas chromatography. The Kluyveromyces strains were characterized by the presence of palmitate, palmitoleate, oleate, and linoleic acid as the major fatty acids. These strains were divided into 3 groups on the basis of fatty acid content. The first group was characterized by a high percentage of linolenic acid, the second group of a lower percentage and the third group by the absence of linolenic acid.  相似文献   

5.
The cellular long-chain fatty acids of 36 strains representing 18 genera of the Saccharomycetaceae, Endomycetaceae, Metchnikowiaceae, Saccharomycodaceae, Schizosaccharomycetaceae and Dipodascaceae were extracted and analyzed as methyl esters by gas chromatography. On the basis of their fatty acid content the set of strains was divided into 6 groups, coinciding with the above families. The members of the Saccharomycetaceae (group I) had a high percentage of oleic acid while the strains classified under the Endomycetaceae (group II) and Metchnikowiaceae (group III) were characterized by oleic acid and linoleic acid as major fatty acids. The Saccharomycodaceae (group IV) had the highest percentage of palmitoleic acid. The Schizosaccharomycetaceae (group V) had the highest percentage of oleic acid, while the Dipodascaceae (group VI) were characterized by a high percentage of linoleic acid.  相似文献   

6.
Coryneform bacteria that were isolated from biofilters which are used for waste gas treatment of animal-rendering plant emissions were differentiated and partially identified by using chemotaxonomic methods. On the basis of the results of a numerical analysis of whole-cell fatty acid profiles, 79 isolates were divided into two major groups; the members of the first group contained saturated and monounsaturated fatty acids, whereas the members of the second group were characterized by iso- and anteiso-branched fatty acids. Division into subclusters was based mainly on quantitative differences in fatty acid composition and was confirmed by the results obtained for additional chemical markers (e.g., respiratory quinones, mycolic acids, polar lipids, cell wall amino acids, and whole-cell sugar patterns). By combining the results obtained for chemotaxonomic analyses that were performed for strains containing saturated and monounsaturated fatty acids, we were able to identify the genus Corynebacterium (two Corynebacterium species were differentiated on the basis of the occurrence of tuberculostearic acid), the genus Gordona, and the genus Mycobacterium. Among the strains that produced iso-anteiso fatty acid patterns, one subgroup was affiliated with the "nicotianae" group of the genus Arthrobacter; however, some strains contained a new combination of chemical markers. Peptidoglycan type A4 alpha, L-Lys-Gly-L-Glu was combined with menaquinones MK-7 and MK-8, whereas peptidoglycan type A4 alpha, L-Lys-L-Glu occurred together with MK-8 and MK-9. The second subgroup was characterized by a new type B peptidoglycan and MK-11, as well as small amounts of MK-12. Differentiation that was based first on chemotaxonomy and second on physiology gave reliable results. Thus, coryneform strains with new characteristics were isolated from biofilters.  相似文献   

7.
Summary The cellular long-chain fatty acids of 69 strains of yeasts, representing 29 species associated with the brewing industry, were extracted by saponification and analyzed asmethyl esters by gas chromatography. The strains were characterized by the presence of palmitic, palmitoleic, stearic, oleic, linoleic and linolenic acid as the major fatty acids. The strains were divided into six groups on the basis of their fatty acid content. With this method it was possible to differentiate between the yeasts on species and, in some instances, on strain level.  相似文献   

8.
The cellular long-chain fatty acids of 36 strains representing 18 genera of the Saccharomycetaceae, Endomycetaceae, Metchnikowiaceae, Saccharomycodaceae, Schizosaccharomycetaceae and Dipodascaceae were extracted and analyzed as methyl esters by gas chromatography. On the basis of their fatty acid content the set of strains was divided into 6 groups, coinciding with the above families. The members of the Saccharomycetaceae (group I) had a high percentage of oleic acid while the strains classified under the Endomycetaceae (group II) and Metchnikowiaceae (group III) were characterized by oleic acid and linoleic acid as major fatty acids. The Saccharomycodaceae (group IV) had the highest percentage of palmitoleic acid. The Schizosaccharomycetaceae (group V) had the highest percentage of oleic acid, while the Dipodascaceae (group VI) were characterized by a high percentage of linoleic acid.This article originally appeared in an incorrect form in Antonie van Leeuwenhoek, Vol. 52, No. 1.  相似文献   

9.
The cultural characteristics and cellular fatty acid composition of 40 strains representing 7 species of Propionibacterium and of 9 cultures of anaerobic corynebacteria were studied. The cultures were characterized by means of 23 separate cultural and biochemical tests. Cultures of the two genera differed consistently in only two reactions; the propionibacteria did not produce indole or liquefy gelatin, whereas the anaerobic corynebacteria were consistently positive with these tests. The fatty acids were extracted from whole cells and examined as methyl esters by gas-liquid chromatography. The most abundant acid in the seven Propionibacterium species was a C(15)-saturated branched-chain acid which was present in both the iso-and anteiso-form. Based on a comparison of the relative abundance of these isomers (i-C(15) and a-C(15)), the species were separated into two groups. P. freudenreichii and P. shermanii (group one) were similar and contained the a-C(15) isomer as the predominant acid. The i-C(15) isomer was the most abundant acid in the second group (P. arabinosum, P. jensenii, P. pentosaceum, P. thoenii, and P. zeae). The fatty acid profiles of the anaerobic corynebacteria were somewhat similar to those of the second group of propionibacteria, but were distinct from the profiles of P. freudenreichii and P. shermanii. The addition of branched-chain amino acids (l-leucine and l-isoleucine) to the growth medium increased the synthesis of the specific fatty acid(s) structurally related to the added amino acid.  相似文献   

10.
11.
The effect of ambient temperature on the composition of intracellular fatty acids and the release of free fatty acids (FFA) into a medium by cyanobacterium Spirulina platensis and eukaryotic microalgae, Chlorella vulgaris and Botryococcus braunii, was studied using their batch cultures. It was found that all the species studied, regardless of their taxonomic status, responded to the temperature regime by similar changes in their intracellular fatty acid composition: the relative content of more unsaturated fatty acids decreased with the elevation of temperature. At the same time, in the prokaryote, this temperature shift blocked, first of all, the elongation of 16:0 to 18:0 and then their further desaturation. In eukaryotes, the change in the desaturation of dienoic to trienoic fatty acids was the most pronounced process. The ratio of dienoic to trienoic fatty acids remained almost unchanged in S. platensis. The relative content of extracellular unsaturated FFA increased in the prokaryotic organism S. platensis at a higher temperature. But no significant changes in the composition of extracellular unsaturated FFA were detected in eukaryotic algae upon temperature elevation.  相似文献   

12.
Twenty-eight axenio planktonic cyanobacterial strains (10 Microcystis, three Oscillatoria, one Spirulina, one Aphanizomenon, 13 Anabaena) were investigated for their fatty acid composition by measurement of non-polar and hydroxy fatty acids. No 2-hydroxy fatty acids were detected in any strain, but 3-hydroxy fatty acids were detected in minor quantities in 24 strains. The highest portion of total fatty acids were non-polar fatty acids. Qualitative and quantitative analyses of 3-hydroxy fatty acids showed no taxonomic value in these strains, while the type of non-polar fatty acid composition was shown to be consistent within Microcystis and Anabaena strains, distinguishing them as type 4, characterized by the presence of 18:4, and type 2, characterized by 18:3 (α) of the Kenyon-Murata system. Two Oscillatoria agardhii Gomont strains were also included in the type 2 group due to the presence of 18: 3 (α), but the difference in characteristics of 16:2 and 16:3 between O. agardhii and Anabaena further divided type 2 into two subgroups: type 2A for Anabaena and type 2B for O. agardhii. A simplified unweighted pair group method with arithmetic averages (UPGMA) dendrogram demonstrated that the classification of 28 strains (Microcystis spp., Anabaena spp., Aphanizomenon flos-aquae (Lemmermann) Ralfs f. gracile (Lemmermann) Elenkin, O. agardhii and Spirullnasubsalsa Oersted ex Gomont based on numerical analysis of non-polar fatty acids corresponded to morphological species criteria, suggesting that non-polar fatty acid composition is a valuable chemical marker in the taxonomy of planktonic cyanobacteria. However, the fatty acid composition in Oscillatoria raciborskii is similar to that of Microcystis and very different from that of O. agardhii, suggesting its special position in Oscillatoria and the chemical diversity in the genus Oscillatoria.  相似文献   

13.
The fatty acid composition of lipopolysaccharides of the strains of Y. enterocolitica, Y. intermedia, Y. frederiksenii and Y. ruckeri studied during cultivation on meat-peptone agar is characterized by the predominance of 3-hydroxytetradecanoic and dodecanoic acids. Closely related to the mentioned bacteria is the strain of Y. kristensenii which is distinguished only by its higher level of hexadecanoic acid. The strains of Y. pseudotuberculosis and the vaccine strain of Y. pestis have a uniform fatty acid composition of lipopolysaccharides with predominance of 3-hydroxytetradecanoic acid. Their relatively low level of dodecanoic acid conditions the characteristic fatty acid spectrum of lipopolysaccharides which differs from that of the above mentioned group of Yersinia. The peculiarities of the fatty acid composition of lipopolysaccharides of both groups of Yersinia are preserved during growth on meat-peptone broth, but the increase in the level of hexadecanoic acid balances the differences between Y. kristensenii, the other Y. enterocolitica-like bacteria and Y. ruckeri. The obtained results confirm close relationship of Y. pseudotuberculosis and Y. pestis, and also of Y. enterocolitica and Y. enterocolitica-like bacteria, showing propinquity of Y. ruckeri to the latter.  相似文献   

14.
The fatty acids oleic, linoleic, and linolenic, each of which has a cis double bond at the delta 9 position, are known to lengthen the circadian period of conidiation (spore formation) of strains of Neurospora crassa carrying the cel mutation. cel confers a partial fatty acid requirement on the organism and has been used to promote incorporation of exogenous fatty acids. To test whether a physical effect imparted by the cis double bonds, such as increased membrane fluidity, is critical for the perturbation of the rhythm, various isomers of these fatty acids were supplemented to the bd csp cel strain. Positional isomers of oleic acid, such as petroselinic (delta 6) and vaccenic (delta 11) acids, and longer-chain isomers, such as eicosenoic (delta 11) and erucic (delta 13) acids, did not lengthen the rhythm. The shorter-chain palmitoleic (delta 9) acid did not give a consistent lengthening of the rhythm; it may be elongated to vaccenic acid. In contrast, gamma-linolenic acid (delta 6,9,12) dramatically lengthened the period. Linoelaidic acid (the trans,trans isomer of linoleic acid) lengthened the period at 22 degrees C, but elaidic acid (the trans isomer of oleic acid) did not. Elaidic acid was shown to exert a lengthening effect, but only at lower temperatures. The data do not support a direct physical action as the source of the fatty acids' "chronobiotic" ability.  相似文献   

15.
A comparison of cellular fatty acid profiles of Desulfovibrio desulfuricans DSM 642 and 14 wild strains of this species, isolated from two completely different environments, soil and the human intestine, was carried out. All the D. desulfuricans strains grown on lactate and sulfate indicated the presence of considerable amounts of i-C15:0, i-C17:1 and C16:0. Although differences in the quantities of individual fatty acids present in each strain were clear in the group of soil strains (similarity, 67.6%), in contrast to almost identical fatty acid patterns (similarity, near 100%) in the intestinal strains, the results were variable within the limits acceptable for species demonstration. The higher similarity of the fatty acid profiles of intestinal strains may be a result of the similarity of biocenoses in the human digestive tract. The coefficients of variability of i-C17:1 and i-C15:0 (the major branched-chain fatty acids), as well as clustering of the investigated strains compared with strains described in the literature after plotting percentages of i-C17:1 fatty acid against i-C15:0 fatty acid, confirmed a certain heterogeneity of cellular fatty acid profiles within the group of soil strains, in contrast to almost ideal homogeneity within the group of intestinal isolates. Intestinal strains contained a higher ratio of saturated to unsaturated fatty acids (2.2 +/- 0.14) than did soil strains (1.6 +/- 0.2; in one case, 2.7). We propose that intestinal D. desulfovibrio bacteria should be assumed to be a highly homogeneous group and should be represented by the strain D. desulfuricans subsp. intestinus in collections of microbial cultures.  相似文献   

16.
Shukla E  Singh SS  Singh P  Mishra AK 《Protoplasma》2012,249(3):651-661
The fatty acid methyl ester (FAME) analysis of the 12 heterocystous cyanobacterial strains showed different fatty acid profiling based on the presence/absence and the percentage of 13 different types of fatty acids. The major fatty acids viz. palmitic acid (16:0), hexadecadienoic acid (16:2), stearic acid (18:0), oleic acid (18:1), linoleic (18:2), and linolenic acid (18:3) were present among all the strains except Cylindrospermum musicola where oleic acid (18:1) was absent. All the strains showed high levels of polyunsaturated fatty acid (PUFAs; 41-68.35%) followed by saturated fatty acid (SAFAs; 1.82-40.66%) and monounsaturated fatty acid (0.85-24.98%). Highest percentage of PUFAs and essential fatty acid (linolenic acid; 18:3) was reported in Scytonema bohnerii which can be used as fatty acid supplement in medical and biotechnological purpose. The cluster analysis based on FAME profiling suggests the presence of two distinct clusters with Euclidean distance ranging from 0 to 25. S. bohnerii of cluster I was distantly related to the other strains of cluster II. The genotypes of cluster II were further divided into two subclusters, i.e., IIa with C. musicola showing great divergence with the other genotypes of IIb which was further subdivided into two groups. Subsubcluster IIb(1) was represented by a genotype, Anabaena sp. whereas subsubcluster IIb(2) was distinguished by two groups, i.e., one group having significant similarity among their three genotypes showed distant relation with the other group having closely related six genotypes. To test the validity of the fatty acid profiles as a marker, cluster analysis has also been generated on the basis of morphological attributes. Our results suggest that FAME profiling might be used as species markers in the study of polyphasic approach based taxonomy and phylogenetic relationship.  相似文献   

17.
Vijayan P  Browse J 《Plant physiology》2002,129(2):876-885
Thylakoid lipid composition in higher plants is characterized by a high level of fatty acid unsaturation. We have screened four mutants of Arabidopsis that have reduced levels of fatty acid unsaturation. Three of the mutant lines tested, fad5, fad6, and the fad3-2 fad7-2 fad8 triple mutant, were more susceptible to photoinhibition than wild-type Arabidopsis, whereas one mutant, fab1, was indistinguishable from wild type. The fad3-2 fad7-2 fad8 triple mutant, which contains no trienoic fatty acids in its thylakoid membranes, was most susceptible to photoinhibition. Detailed investigation of photoinhibition in the triple mutant revealed that the rate of photoinactivation of PSII was the same in wild-type and mutant plants. However, the recovery of photoinactivated PSII was slower in fad3-2 fad7-2 fad8, relative to wild type, at all temperatures below 27 degrees C. These results indicate that trienoic fatty acids of thylakoid membrane lipids are required for low-temperature recovery from photoinhibition in Arabidopsis.  相似文献   

18.
Trienoic fatty acids, namely -linolenic acid and hexadecatrienoic acid, present in leaf lipids are produced by -3 fatty acid desaturases located in the endoplasmic reticulum and plastid membranes. The changes in the level of trienoic fatty acids during leaf maturation were investigated in wild-type plants of Arabidopsis thaliana (L.) Heynh. and in the fad7 mutant deficient in the activity of a plastid -3 desaturase. The levels of trienoic fatty acids increased in 26 °C- and 15 °C-grown wild-type plants with maturation of leaves. The increase in trienoic fatty acids was mainly due to galactolipids enriched in plastid membranes. In addition, the relative levels of trienoic fatty acids in major glycerolipids, including phospholipids enriched in the endoplasmic reticulum membranes, also increased with leaf maturation. By contrast, when the fad7 mutant was grown at 26 °C, the relative levels of trienoic fatty acids in individual lipids decreased with leaf maturation. The decreases in the levels of trienoic fatty acids, however, were alleviated when the fad7 mutant was grown at 15 °C. These results suggest that the plastid -3 desaturase plays a major role in increasing the levels of trienoic fatty acids with leaf maturation.Abbreviations 163 hexadecatrienoic acid - 183 -linolenic acid - DGD digalactosyldiacylglycerol - MGD monogalactosyldiacylglycerol - PC phosphatidylcholine - PE phosphatidylethanolamine - TA trienoic fatty acid - WT wild type - -3 refers to the position of the double bond from the methyl end of a fatty acid This research was supported in part by Grants-in-Aid for Scientific research (#07251214 and #06804050 to K.I.) from the Ministry of Education, Science and Culture, Japan, and by the research grant from Shorai Foundation.  相似文献   

19.
The effect of the carbon to nitrogen (C/N) ratio of the medium and the aeration rate on the lipid content and fatty acid composition ofChlorella sorokiniana was investigated using heterotrophic, batch culture. Both parameters had a significant effect. A C/N ratio of approximately 20, was found to indicate a change from carbon to nitrogen limitation forC. sorokiniana. Cell lipid content was at a minimum at this value and increased at both higher and lower C/N values. Low C/N ratios favoured a high proportion of trienoic fatty acids at the expense of monoenoic acids. Aeration enhanced cell growth, fatty acid yield and the synthesis of unsaturated dienoic and trienoic fatty acids, but reduced cell lipid content. The results demonstrate that the fatty acid composition and lipid content of heterotrophically-grown microalgae can be favourably manipulated by varying culture conditions.  相似文献   

20.
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