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1.
Fatty acid composition of lipids isolated from spores of different fern groups show differences between the families whereas species variations within the families are smaller. As in seed fats, the spore lipids are mainly triglycerides, with the exception of Osmunda where free fatty acids accumulate. The spore lipids contain as major components oleic, linoleic, and palmitic acid although those of the sporophylls contain C-20 polyunsaturated acids.  相似文献   

2.
Fatty acid composition of bacterial membrane and wall lipids   总被引:9,自引:0,他引:9  
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3.
The changes in viability, susceptibility to peroxidation and fatty acid composition of total phospholipid were studied in boar spermatozoa during 5 day liquid storage in a standard or alpha-tocopherol (alphaT) enriched diluent. The sperm rich fraction of the ejaculates was collected from 6-month old boars. Sperm viability progressively decreased during storage and alphaT inclusion into the diluent significantly inhibited this trend. alphaT inclusion also decreased significantly peroxidation (TBARS production of spermatozoa). Spermatozoa stored in the treatment diluent became rapidly enriched in alphaT with a concomitant decrease of alphaT content in the medium. The proportion of polyunsaturates, mainly 22:6n-3, decreased with a complementary increase in the content of the saturates, mainly 18:0. The inclusion of alphaT into the diluent was effective in totally preventing the significant decrease of 22:6n-3 observed in sperm phospholipid in the control samples during the storage period. It is concluded that the alphaT inclusion in the boar semen diluent increased cell viability through its prevention of an oxidative reduction in the levels of the major polyunsaturated fatty acids, namely 22:6n-3.  相似文献   

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5.
Rapid warming of semen from 5 to 37 degrees C caused visible damage to the acrosomes of bull and rabbit spermatozoa. The degree and type of damage varied with the species, the bull being the more resistant. While vesiculation was observed in rabbit spermatozoa, neither warm nor cold shock resulted in this defect in the bull. Warm shock of bull spermatozoa caused acrosomal knobbing in an anterior region of the head. Spermatozoa with thread and/or droplet-like structures were frequently observed in bull semen after cold shock.  相似文献   

6.
Fatty acid composition of the lipids from plague microbe   总被引:1,自引:0,他引:1  
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8.
Fatty acid composition of lipids which copurify with band 3   总被引:1,自引:0,他引:1  
In a previous study (L. R. Maneri and P. S. Low (1988) J. Biol. Chem. 263, 16170-16178) we determined that the anion transport protein, band 3, was significantly stabilized by lipids containing saturated and/or long chain fatty acids. To determine whether this thermodynamic preference is reflected in the composition of lipids tightly associating with the anion transporter in vivo, we have analyzed the fatty acid content of phospholipids co-isolating with the purified integral domain of band 3. Our data demonstrate that although stearic acid comprises only 14% of the bulk lipid fatty acids of the red cell membrane, it constitutes -68% of the fatty acids of lipids co-isolating with band 3. Certain other long chain fatty acids were also enriched in the adherent lipids. These results suggest that the fatty acids which most effectively stabilize band 3 also have the highest affinity for the transport protein.  相似文献   

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10.
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   

11.
Activation of bovine chymotrypsinogen is catalyzed with increasing velocity by human, rabbit, boar, bull and ram acrosin. Antiboar-acrosin rabbit gamma-globulins cause a significant reduction in the proenzyme activation rate induced by boar and bull acrosin, but only a weak reduction or none if ram or rabbit acrosin is the activating agent. The antiboar-acrosin gamma-globulins from sheep strongly inhibit chymotrypsinogen activation by ram, bull and boar acrosin, and significantly inhibit the human acrosin-catalyzed reaction.  相似文献   

12.
Generally, both subjective and computer-assisted (HTM-2000 motility analyzer) assessment of sperm motility in fresh and in frozen-thawed semen of bulls, boars and bucks yields comparable results. However, the use of a motility analyzer renders consistently more accurate estimates, especially when that motility is vigorous as in fresh bull semen.  相似文献   

13.
14.
The models "population--Nocardia-like spontaneous mutants" for 14 cultures of Streptomycetes and Streptoverticillium were used to assess the fatty acid composition of lipids as a criterion for generic differentiation of Streptomyces and Nocardia cultures. The composition of fatty acids in the Nocardia-like mutant Str. kanamyceticus RIA-771 was found to be identical with that of Nocardia asteroides RIA-43 and Nocardia brasiliensis RIA-440, i. e. generic chemotaxonomic traits "overlapped" in the process of spontaneous intraspecial variability. In different strains of one and the same species as well as in five different species, the quantitative composition of fatty acids either hardly changed in the process of intraspecial variability or the ratio between fatty acids changed, so that Nocardia-like mutants resembled typical cultures of the Nocardia genus in this characteristics. The results suggest that the quantitative composition of fatty acids of lipids cannot be regarded as a sufficiently reliable criterion for generic differentiation of Steptomyces and Nocardia cultures. This trait should be used only for additional characterization of cultures.  相似文献   

15.
1. The fatty acid compositions of the plasma lipids of newborn unsuckled lambs, kids, calves and piglets have been determined and compared with those of maternal plasma lipids at parturition. 2. The predominating plasma fatty acids in the newborn of all species are palmitic acid, C(16:1) acid, stearic acid and C(18:1) acid. This finding is consistent with the synthesis of the major proportion of fatty acids from non-lipid sources within the foetus. 3. Very small amounts of C(18:2) acid and C(18:3) acid are present in the plasma lipids of newborn ruminants, although considerable amounts of these fatty acids are contained in maternal plasma. The plasma fatty acids of the newborn piglet contained 5.5% of C(18:2) acid, those of the calf 2.0%, and those of the lamb and kid less than 1.0%. This finding is discussed in relation to the higher content of C(18:2) acid in the plasma non-esterified fatty acid fraction of the sow (15%) compared with that of the ruminant (less than 4%). 4. In the lamb and kid, but not in the calf or piglet, a C(20:3) acid was detected in plasma lipids that was very similar to, if not identical with, the C(20:3) acid that accumulates in the plasma of animals given diets low in essential fatty acids. The possible significance of this finding is discussed. 5. The cholesteryl esters of cow plasma were found to contain a higher percentage (43%) of C(18:3) acid than those of goat and sheep plasma (5-10%). The possible reasons for this difference are discussed.  相似文献   

16.
The composition of membrane fatty lipid acids and the content of polyunsaturation of fatty acids have been shown not to be the leading factors in the formation of radioresistance cells.  相似文献   

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Ejaculated spermatozoa of boars, bulls, rabbits, and rams were fixed with glutaraldehyde and embedded in glycolmethacrylate. Thin sections were treated with phosphotungstic acid at low pH in order to localize cellular glycoproteins stained by the PAS technique at the light microscope level. At the ultrastructural level the glycoproteins were segregated in the anterior segment of mature spermatozoa. The distribution of these glycoproteins in the anterior segment was not homogeneous; it appeared species-specific in detail, but as a rule, the maximum concentration was observed in a superficial layer, especially in the marginal thickening. The localization of other acrosomal components (eg, crystalline and basic proteins) is also reviewed. The origin and significance of the segregation of proteins and glycoproteins in the acrosome are discussed in relation to the fact that the acrosomal enzymes analyzed so far are glycoproteins.  相似文献   

20.
The purpose of this work was to see whether hyperlipaemia observed in genetically obese Zucker rats (fa/fa) was associated with differences in fatty-acid composition of plasma triacylglycerols, plasma phospholipids and of platelet phospholipids, in comparison with the control lean rats (Fa/-). Results showed that plasma triacylglycerols and phospholipids were increased in obese rats. In triacylglycerols, the amount of saturated and monounsaturated fatty acids was highly increased whereas the amount of the n-6 and n-3 polyunsaturated fatty acids was little modified. In plasma phospholipids, saturated and monounsaturated fatty acids were also increased, as were the n-3 fatty acids (except C 18:3 n-3); the n-6 fatty acids were little increased except C 20:3 n-6 which was markedly increased. These results concerning the amounts of fatty acids have their counterpart in their relative proportions of fatty acids. Data thus obtained suggest that conversion of linoleic acid (C 18:2 n-6) into arachidonic acid (C 20:4 n-6) was decreased in obese rats, particularly the delta 5 desaturation step. On the contrary, conversion of linolenic acid (C 18:3 n-3) into higher polyenes seemed increased. Thrombocytosis was not modified in the obese rat, but the volume of the platelets was increased. Platelet phospholipids exhibited the same modifications as plasma phospholipids but with different magnitude. Saturated and monounsaturated fatty acids were little augmented, n-3 fatty acids were more augmented (except C 18:3 n-3 acid which was unchanged); n-6 fatty acids were not modified except C 20:3 n-6 acid which was highly increased.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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