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The composition of the phospholipid-bound fatty acids in the spermatozoa of the turkey, Meleagris gallopavo, and fowl, Gallus domesticus, was studied. The types of fatty acids were similar in the two birds. The ratio of polyunsaturated : saturated fatty acids was generally low but slightly higher in the turkey than in the fowl. The significance of the findings in relation to the origin of the semen collected in these gallinaceous birds and the greater difficulty of freezing turkey spermatozoa was discussed.  相似文献   

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We examined the free amino acid composition of hemolymph from representatives of five spider families with an interest in knowing if the amino acid profile in the hemolymph of orb-web-building spiders reflects the high demands for small organic compounds in the sticky droplets of their webs. In nearly all analyses, on both orb and non-orb builders, glutamine was the most abundant free amino acid. Glycine, taurine, proline, histidine, and alanine also tended to be well-represented in orb and non-orb builders. While indications of taxon-specific differences in amino acid composition were observed, it was not apparent that two presumptive precursors (glutamine, taurine) of orb web sticky droplet compounds were uniquely enriched in araneids (orb builders). However, total amino acid concentrations were invariably highest in the araneids and especially so in overwintering juveniles, even as several of the essential amino acids declined during this winter diapause. Comparing the data from this study with those from earlier studies revealed a number of discrepancies. The possible origins of these differences are discussed.  相似文献   

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Most invertebrates, particularly those of marine origin, have relatively high concentrations of free amino acids which are considered an important constituent of their osmoregulatory mechanisms [1]. Very little information is available on the free amino acid distribution in Porifera [2,3]. Common amino acids in some sponges were recognised by paper chromatography by Inskip and Cassidy [4] and Ackermann et al. [5,6] included a few sponges in their survey of the occurence of nitrogen compounds in marine invertebrates. More recently Bergquist and Hartman [7] surveyed semiquantitatively the distribution of free amino acids in several sponges. In the present paper we report on the amino acid composition of 12 species of sponges belonging to the class Demospongiae as a part of a study on the metabolites of Porifera [8]. Fresh sponges were extracted with aqueous ethanol. The organic solvent was removed and the aqueous solution, after removal of the ether soluble compounds, was separated into cationic, anionic and neutral fractions by ion-exchange chromatography. The cation fraction was analysed for amino acids using an automatic amino acid analyser. The results, which are presented in Table 1, show that all species of sponges examined have a similar composition in common amino acids. Glycine almost always appears as the dominant protein amino acid, followed by high concentrations of alanine and glutamic acid, whereas relatively lower concentrations of basic amino acids are present. In Axinella cannabina, Chondrosia reniformis, Chondrilla nucula, Cliona viridis and Hymeniacidon sanguinea, glycine represents more than 77% of the total amino acids. The high percentage of free glycine (90.4%) in Chondrosia reniformis is noteworthy. The anionic and the neutral fractions were examined for sulfur-containing amino acids using PC. Taurine (Table 2) was detected in all the Porifera examined; this is in agreement with previous observations [5–7]. N-Methyltaurine was identified in some of the species examined, whereas neither N,N-dimethyltaurine nor N,N,N-trimethyltaurine were found.  相似文献   

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In this work have been reported the research results tending to establish the free amino acidis concentration, existing in the calf embryos. The free embryonal amino acidis composition has been determined through an analysis effected with "Amino Acid Analyzer". Such studies, which conern the researches under execution in our Institute on the chemical composition of the calf embryos furnish the biochemical determination of a biological material, used in some Nations like a commercial product.  相似文献   

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Pollens from Pinus canariensis, P. nigra, P. pinaster, P. pinea, Castanea sativa, Magnolia grandiflora, Olea sativa cv frantoio, cv itrana, cv pisciottana were examined for their free amino acid composition. A large amount of proline was found in all species; pollens of Olea also contain a large amount of serine.  相似文献   

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The free amino acids were determined in different parts of maize seedlings (seeds, roots and shoots), 0, 2, 4 and 6 days after sowing.  相似文献   

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  • 1.1. It was confirmed that, under anaerobic conditions, fowl spermatozoa formed lactate from glucose thirteen times faster than turkey spermatozoa.
  • 2.2. The profiles of glycolytic enzyme activities were similar for spermatozoa from both species; however fowl spermatozoal activities were generally 2- to 4-fold higher.
  • 3.3. Exceptions were glycerophosphate mutase and lactate dehydrogenase activities which were respectively 9.5 and 41 times greater in fowl spermatozoa.
  • 4.4. In both species, spermatozoal glyceraldehyde-3-phosphate dehydrogenase had the lowest activity of the glycolytic enzymes.
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