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1.
Summary A family with one homozygote and three heterozygotes for hemoglobin Stanleyville II (78 AsnLys) has been analyzed by -globin gene mapping. The pattern of restriction fragments with the enzymes BamHI and BglII demonstrated that the globin variant is associated with a 3.7-kb -globin gene deletion.  相似文献   

2.
Zusammenfassung In Rohhomogenaten aus gefriergetrockneten Kryostat-schnitten von verschiedenen Rattenorganen werden die K m und V max der neutralen und sauren -d-Glucosidase bestimmt und der Einfluß von pH, Substrat- und Enzymkonzentration und Inkubationszeit auf die Aktivität fluorometrisch mit 4-Methylumbelliferyl-und 2-Naphthyl--d-glucosid als Substraten ermittelt.Mit den biochemischen Daten werden 2 mikrochemische Ansätze zur fluorometrischen Messung dieser Glykosidasen entwickelt und die saure und neutrale -Glucosidase in Gruppen von Epithelzellen nach Isolierung aus gefriergetrockneten Kryostatschnitten von Nebenhoden, Jejunum, Ilium, Niere und Leber untersucht. Im Vergleich zum 2-Naphthylderivat sind beide -Glucosidasen mit 4-Methylumbelliferyl--d-glucosid weniger aktiv. Allerdings fluoresziert 4-Methylumbelliferon etwa 100mal intensiver als 2-Naphthol, so daß das Methylumbelliferonderivat zur Messung der -Glucosidasen speziell in schwach aktiven Zellen der 2-Naphthylverbindung vorzuziehen ist.
Microchemical investigation of -d-glucosidases using 4-methylumbelliferyl-and 2-naphthyl--d-glucoside
Summary In crude homogenates prepared from freeze-dried cryostate sections of various rat organs the K m and V max of acid and neutral -glucosidase as well as the effect of the pH, substrate and enzyme concentration and the incubation time on the activity were determined fluorometrically with 4-methylumbelliferyl-and 2-naphthyl -d-glucoside as substrates.On the basis of the biochemical data 2 assays were developed for the microchemical measurement of both -glucosidases in groups of epithelial cells isolated from freeze-dried cryostate sections of the epididymis, jejunum, ilium, liver and kidney of suckling and adult rats. The rate of hydrolysis of 2-naphthyl and 4-methylumbelliferyl -d-glucoside differs moderately. However, due to the higher sensitivity of 4-methylumbelliferone the methylumbelliferyl derivative is preferable especially for the evaluation of -d-glucosidases in cells with low enzyme activity.
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3.
The parallel /-barrel domain consisting of eight parallel -sheets surrounded by eight -helices has been currently identified in crystal structures of more than 20 enzymes. This type of protein folding motif makes it possible to catalyze various biochemical reactions on a variety of substrates (i.e., it seems to be robust enough so that different enzymatic functionalities could be designed on it). In spite of many efforts aimed at elucidation of evolutionary history of the present-day /-barrels, a challenging question remains unanswered: How has the parallel /-barrel fold arisen? Although the complete sequence comparison of all /-barrel amino acid sequences is not yet available, several sequence similarities have been revealed by using the highly conserved regions of -amylase as structural templates. Since many starch-processing enzymes adopt the parallel /-barrel structure these enzymes might be useful in the search for evolutionary relationships of the whole parallel eight-folded /-barrel enzyme family.  相似文献   

4.
The present work investigated the possibility of cleavage of -linkages between mannose or galactose and serine/threonine residues by -mannosidase and -galactosidase. The study was carried out initially with model synthetic compounds imitating theO-glycosidic bond in glycoproteins, and further with glucoamylase. It was shown that -mannosidase and -galactosidase can hydrolyse these linkages after proteolytic digestion of glucosamylase.  相似文献   

5.
Two alternatively spliced forms of human PPAR mRNA, PPAR1 and PPAR2, have been identified. PPAR1 mRNA gives rise to an active PPAR protein while PPAR2 mRNA gives rise to a form of PPAR which lacks the ligand-binding domain. PPAR2 is unable to activate a peroxisome proliferator response element (PPRE) reporter gene construct in transient transfection assays. Both PPAR1 and PPAR2 mRNA are present in human liver, kidney, testes, heart, small intestine, and smooth muscle. In human liver, PPAR2 mRNA abundance is approximately half that of PPAR1 mRNA; a correlation analysis of PPAR1 and PPAR2 mRNA mass revealed an r-value of 0.75 (n = 18). Additional studies with intact liver from various species, showed that the PPAR2/PPAR1 mRNA ratios in rat, rabbit, and mouse liver were less than 0.10; significantly lower than the 0.3 and 0.5 ratios observed in monkey and human livers, respectively. To determine if a high PPAR2/PPAR1 mRNA ratio was associated with insensitivity to peroxisome proliferators, we treated human, rat, and rabbit hepatocytes with WY14643, a potent PPARa activator, and measured acyl CoA oxidase (ACO) mRNA levels. Rat ACO mRNA levels increased markedly in response to WY14643 while human and rabbit hepatocytes were unresponsive. Thus, although the PPAR2/PPAR1 mRNA ratio is low in rabbits, this species is not responsive to peroxisome proliferators. Further studies with male and female rats, which vary significantly in their response to peroxisome proliferators, showed little difference in the ratio of PPAR2/PPAR1 mRNA. These data suggest that selective PPAR2 mRNA expression is not the basis for differential species or gender responses to peroxisome proliferators.  相似文献   

6.
-Sarcin is a ribosome inactivating protein produced by the mouldAspergillus giganteus. The effect of this protein on eight different tumour cell lines has been studied in the absence of any agent affecting membrane permeability. The protein is cytotoxic for all the tumour cell lines considered. -Sarcin modifies the cell proliferation pattern by inhibiting the protein biosynthesis of the cultured cells. No membrane damage produced by -sarcin has been observed by measuring lactic dehydrogenase leakage. Alteration on the cell mitochondrial activity has not been detected upon treatment with -sarcin. Differences on the extent of the protein binding to the cells have been observed by flow cytometric measurements. The kinetic analysis of the protein biosynthesis inhibition produced by -sarcin reveals an -sarcin concentration-dependent lag phase followed by a first order decrease of the protein synthesis rate. This parameter is dependent on the external -sarcin concentration. A saturable component for the action of -sarcin is also deduced from these experiments. Results are discussed in terms of the protein passage across the cell membrane as the potential rate-limiting step for the action of -sarcin.  相似文献   

7.
Summary The crystallins are highly conserved structural proteins universally found in the eye lens of all vertebrate species. In mammals, three immunologically distinct classes are present, -, -, and -crystallins, and each class represents a multigene family. The -crystallin gene family consists of 1-crystallin (CRYA1) and 2-crystallin (CRYA2) genes (previously designated A-and B-crystallin, respectively), which show extensive sequence homology. We constructed a synthetic oligonucleotide probe of 25 bases corresponding to a specific region of the human 1-crystallin gene sequence. This 25-mer probe bears little sequence homology to human 2-crystallin gene and does not cross-hybridize to 2-crystallin sequences in Southern blot analysis. Using this unique synthetic probe, we have demonstrated the identity of the 1-crystallin gene in human genomic DNA. In addition, we have also confirmed its chromosomal location on human chromosome 21. Finally, we have regionally localized the gene to q22.3 by using both Southern blot analysis of a panel of cell hybrids containing different parts of human chromosome 21, and in situ hybridization to metaphase chromosomes. The use of synthetic oligonucleotide probes specific for individual genes should be useful in identifying and mapping members of multigene families.  相似文献   

8.
    
Summary The production of sex pheromones responsible for the induction of the sexual agglutination ability in the mutants of the mating type locus, mata1, mat1 and mat2, was examined. mata1 cells behaved just like wild-type MATa cells in the production of a pheromone and responsiveness to pheromone. On the other hand, mat1 cells showed neither a nor ability in the production of and the agglutination ability induction by sex pheromones. Cells carrying mat2 secreted a pheromone but not pheromone and showed the ability to inactivate pheromone. However, mat2 cells responded to neither a nor pheromone in the induction of sexual agglutionation ability.  相似文献   

9.
Zusammenfassung Verglichen mit 1- und 2-Naphthyl--d-glucosid,--d-galactosid,--d-glucuronid,--d-N-acetylglucosaminid,--d-glucosid,--d-galactosid und--d-mannosid werden 1- und 2-Naphthyl--l-fucosid schneller oder im gleichen Ausmaß von Homogenaten verschiedener Rattenorgane hydrolysiert. Trotzdem fällt der histochemische Nachweis der -l-Fucosidasen methodenunabhängig im Gegensatz zu dem der anderen Glykosidasen überwiegend negativ aus. Ursache dafür ist die massive Hemmung der -l-Fucosidase durch Aldehydfixation und Diazoniumsalze; die Inhibitionsrate liegt bei 90% bzw. zwischen 85 und 98%; die - und -d-Glucosidase, - und -d-Galactosidase, -d-Mannosidase, -d-Glucuronidase sowie -d-N-Acetylglucosaminidase werden durch Aldehydfixation oder Kuppler höchstens zu 70% gehemmt. Daher können 1- und 2-Naphthyl--l-fucosid für die histochemische Darstellung der -l-Fucosidase nicht einschränkungslos empfohlen werden. Kleine Mengen Dimethylformamid hemmen die meisten Glykosidasen nicht.Für biochemische Messungen der -l-Fucosidase eignet sich speziell 1-Naphthyl--l-fucosid und läßt sich an Stelle von p-Nitrophenyl--l-fucosid werwenden. Bei der fluorometrischen Untersuchung der -l-Fucosidase in Rattenorganen mit dem 2-Naphthylderivat ergeben sich bemerkenswerte Aktivitätsunterschiede.
Suitability of naphthyl--l-fucosides for the investigation of -l-fucosidases
Summary In comparison with 1- and 2-naphthyl -d-glucoside, -d-galactoside, -d-glucuronide, -d-N-acetylglucosaminide, -d-glucoside, -d-galactoside and -d-mannoside 1- and 2-naphthyl -l-fucoside are hydrolyzed more quickly or to the same extent by homogenates prepared from freezedried cryostate sections of various rat organs. Nevertheless, when the fucosides are employed for the histochemical demonstration of -l-fucosidase mostly negative data were obtained independent on the method used, whereas all other naphthyl glycosides deliver positive results. The reasons for these discrepancies are the marked inhibition of -l-fucosidase by aldehyde fixation and diazonium salts. Then, -l-fucosidase activity is suppressed to 90% and between 85 and 98% respectively; the inhibition of - and -d-glucosidase, - and -d-galactosidase, -d-mannosidase, -d-glucuronidase and -d-N-acetylglucosaminidase by the fixative or coupling reagent does not exceed 70%. Therefore 1- and 2-naphthyl -l-fucoside cannot be recommended in general for histochemical purposes. Small amounts of dimethylformamide do not influence the activity of most of the glycosidases investigated.For biochemical measurements, however, especially 1-naphthyl -l-fucoside represents a suitable alternative in a fluorometric procedure instead of p-nitrophenyl -l-fucoside used for the photometric evaluation of -l-fucosidase. With the fluorometric method the enzyme was measured in rat organs, which posses remarkably different activities of -l-fucosidase.
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10.
Four glycosidases were analyzed in 10 mm apical segments prepared from growing roots (15 mm) of Zea mays L. The pH optima were found to be 5.8 for -glucosidase, 4.4 for -galactosidase, 6.4 for -glucosidase and 6.0 for -galactosidase. The -glucosidase showed 4-fold higher activity than the -galactosidase. The distribution of the -glucosidase activity was signifcantly different from that of the -galactosidase, -glucosidase and -galactosidase.Abbreviations -Glu -glucosidase - -Gal -galactosidase - -Glu -glucosidase - -Gal -galactosidase  相似文献   

11.
Calf lens A-crystallin isolated by reversed-phase HPLC demonstrates a slightly more hydrophobic profile than B-crystallin. Fluorescent probes in addition to bis-ANS, like cis-parinaric acid (PA) and pyrene, show higher quantum yields or Ham ratios when bound to A-crystallin than to B-crystallin at room temperature. Bis-ANS binding to both A- and B-crystallin decreases with increase in temperature. At room temperature, the chaperone-like activity of A-crystallin is lower than that of B-crystallin whereas at higher temperatures, A-crystallin shows significantly higher protection against aggregation of substrate proteins compared to B-crystallin. Therefore, calf lens A-crystallin is more hydrophobic than B-crystallin and chaperone-like activity of -crystallin subunits is not quantitatively related to their hydrophobicity.  相似文献   

12.
Summary Microorganisms which produce strong raw-starch degrading enzymes were isolated from soil using a medium containing a unique carbon source, -amylase resistant starch (-RS), which is insoluble in water and hardly digested with Bacillus amyloliquefaciens -amylase. Among the isolates, three strains showing high activities were characterized. Two of them, K-27 (fungus) and K-28 (yeast), produced -amylase and glucoamylase, and the final product from starch was only glucose. The third strain, K-2, was a bacterium and produced -amylase, which produced glucose and malto-oligosaccharides from starch. The enzyme preparation of these strains degraded raw corn starch rapidly.  相似文献   

13.
The specific features of the topology of spectral powers and coherent interregional interrelationships in the narrow, individually determined -, -, 1-, 2-, and 3-frequency bands were studied by means of high-resolution EEG (62 channels) in novice and experienced meditators (NMs and EMs) at rest and under the conditions of generation of an altered state of consciousness characterized by inactivation of cognitive activity and the occurrence of a positive emotional experience of happiness. EMs in the meditation-free state were found to be characterized by a shift in the values of the individual frequency to a lower-frequency region of the spectrum, along with higher, compared to NMs, -, 1-, 2-, and 3-band power values, which probably reflects the cumulative character of the influence of long-term meditative practice. The effective achievement of altered states of consciousness in EMs was associated with an increase in the local - and 1 powers in the anterior cortical areas, as well as long-distance coherence between the prefrontal and posterior associative cortex with the formation of a center of gravity in the left prefrontal region (lead AF 3). According to the data of the correlation analysis of the EEG power values and the data of subjective scaling of the meditation state, the -power values were positively associated with positive emotional experiences and negatively associated with the level of mental activity. The results of this study are consistent with current concepts that the and activities in narrow frequency bands reflect the activity of multifunctional neuronal networks selectively associated with processes of cognitive and affective activity.  相似文献   

14.
Zusammenfassung In 2 Versuchsserien wurden Kohlmeisen(Parus major) und japanische Möwchen(Lonchura striata var.domestica) einzeln und schallisoliert gehalten. In der ersten Versuchsserie, in der alle Vögel einen dunklen Schlafkasten hatten, wurde der Einfluß der Beleuchtungsstärke auf die Periode () der Hüpfaktivität und auf das Verhältnis von Aktivitätszeit zu Ruhezeit ( : -Verhältnis) untersucht. Sowhol Kohlmeisen als auch japanische Möwchen folgen der Regel, daß mit wachsender Beleuchtungsstärke die Periode kürzer und das : -Verhältnis größer wird.In der 2. Serie wurde der Einfluß Ruhe im dunklen Schlafkasten auf die Periodenlänge und auf das : -Verhältnis untersucht. Es wurden die Messungen aus Bedingung 1 (der Vogel hat einen dunklen Schlafkasten zur Verfügung) mit den Messungen aus Bedingung 2 (der Vogel hat keinen oder einen hellen Schlafkasten zur Verfügung) verglichen. Das Ergebnis bei Kohlmeisen entspricht den Befunden bei konstantem Licht verschiedener Intensität. Unter Bedingung 1 ist länger und das : -Verhältnis kleiner als in Bedingung 2. Das Ausmaß der Änderung von nach Fortnahme des dunklen Kastens ist unabhängig von der Periodenlänge in Bedingung 1. Das Ausmaß der änderung von : ist unabhängig von a : in Bedingung 1, jedoch schwach negativ korreliert mit der Periodenlänge in Bedingung 1.Bei japanischen Möwchen entsprechen die Ergebnisse dieser Versuchsserie nicht der Regel für tagaktive Vögel. Mit Benützen des dunklen Schlafkastens ist kürzer als ohne den Schlafkasten. Ohne den Schlafkasten ist etwa 24 Std. Das : -Verhältnis ist in Bedingung 1 unter bestimmten Voraussetzungen kleiner als in Bedingung 2. Das Ausmaß der Änderung von nach Fortnahme des Kastens ist mit der dazugehörigen Periode in Bedingung 1 hochsignifikant korreliert (Regressionskoeffizient b=-1.01, Korrelationskoeffizient r=0.89). Ebenfalls ist das Ausmaß der Änderung von : nach Fortnahme des Kastens mit : aus Bedingung 1 korreliert; es scheint, als würde ein bevorzugtes : -Verhältnis von etwa 2.0 eingeregelt.Die Ergebnisse werden im Hinblick auf 4 Punkte diskutiert: 1) Das circadiane System arbeitet innerhalb eines engen Bereiches von - und : -Werten optimal. 2) Der Optimalbereich wird bevorzugt unter ungünstigen Bedingungen angestrebt. 3) Der Entzug des dunklen Schlafkastens belastet japanische Möwchen mehr als Kohlmeisen. 4) Bei japanischen Möwchen wird in Bedingung 1 durch fortplfanzungsphysiologischen Einfluß verkürzt.
Circadian activity rhythms of birds with and without a dark nest box
Summary Perch-hopping activity of Great tits(Parus major) and Bengales finches(Lonchura striata domestica), housed individually in soundproof boxes, was studied in two series of experiments. In the first series all birds had access to a dark nest box, in which they retired during their subjective night. In this experiment the effect of light intensity on the freerunning circadian activity rhythm was investigated. Both Great tits and Bengalese finches obey the circadian rule by responding to an increase in light intensity with shortening the circadian period () and with an increase of the ratio of activity time and rest time ( : ).In the second series of experiments the influence of sleeping in the dark nest box on both circadian period and : -ratio was studied. The results of two experimental conditions — without and with access to a dark nest box — were compared. In the Great tits, the results are in agreement with the effect of light intensity: when a dark nestbox is available, is longer and the : -ratio is smaller than in the absence of a nest box. The magnitude of the change in free-running period after removal of the nest box is independent of the original value of ; the amount of change : -ratio is likewise independent of the original : -ratio, but is weakly correlated to the original .InLonchura striata var. domestica, removal of the dark nest box leads to a lenghtening of the free-running period to about 24 hours; the : -ratio is smaller in the presence of a dark nestbox, if certain other conditions are fulfilled. The magnitude of the change in after removal of the nest box is highly correlated to the original free-running period (r=-0.89) in such a way that, without nest box, the period approaches a value of 24 hours. Also, the amount of change in : -ratio due to nest box removal is negatively correlated to the original : -ratio. A probably preferred : -ratio of 2.0 is adopted.These results are discussed in the view of 4 points: 1) The circadian system operates at its optimum within a narrow range of - and : -values. 2) This optimal range is especially adopted when conditions become adverse. 3) Removal of the dark nest box results in a more stressful situation for Bengalese finches than for Great tits. 4) In the Bengalese finches, is shortened in the presence of a nest box due to effects on reproductive physiology.


Herrn Prof. Dr. JürgenAschoff zum 60. Geburtstag gewidemt.  相似文献   

15.
Each cryptomonad strain contains only a single spectroscopic type of biliprotein. These biliproteins are isolated as 50000 kDa '2 complexes which carry one bilin on the and three on the subunit. Six different bilins are present on the cryptomonad biliproteins, two of which (phycocyanobilin and phycoerythrobilin) also occur in cyanobacterial and rhodophytan biliproteins, while four are known only in the cryptomonads. The subunit is encoded on the chloroplast genome, whereas the subunits are encoded by a small nuclear multigene family. The subunits of all cryptomonad biliproteins, regardless of spectroscopic type, have highly conserved amino acid sequences, which show > 80% identity with those of rhodophytan phycoerythrin subunits. In contrast, cyanobacteria and red algal chloroplasts each contain several spectroscopically distinct biliproteins organized into macromolecular complexes (phycobilisomes). The data on biliproteins, as well as several other lines of evidence, indicate that the cryptomonad biliprotein antenna system is primitive and antedates that of the cyanobacteria. It is proposed that the gene encoding the cryptomonad biliprotein subunit is the ancestral gene of the gene family encoding cyanobacterial and rhodophytan biliprotein and subunits.Abbreviations Chl chlorophyll - CER chloroplast endoplasmic reticulum - SSU rRNA small subunit ribosomal RNA  相似文献   

16.
K99 lectin fromEscherichia coli was purified and biotinylated via its carboxyl groups using biocytin hydrazide and a water soluble carbodiimide. Biotinylation of two out of the nine carboxyl groups was sufficient to permit detection of the lectin by avidin and did not cause any loss of the haemagglutinating activity. It was demonstrated that the biotinylated K99 lectin retained other important properties of native K99 and that it will probably become a very sensitive detecting reagent. Indeed, it was able to bind to HeLa cells, as do intact bacteria carrying K99 fimbriae, and also to recognizeN-glycolyl-neuraminyl-lactosyl-ceramide in an overlay binding assay. Abbreviations: NeuAc,N-acetylneuraminic acid; NeuGc,N-glycolylneuraminic acid; PBS, phosphate buffered saline (0.9% NaCl containing 150mm sodium phosphate, pH 7.2); LPS, lipopolysaccharide; BCHZ, biocytin hydrazide; EDC, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide; BSA, bovine serum albumin; SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis; DMEM, Dulbecco's modified Eagle medium. For the gangliosides, trivial names and structures are given according to the recommendations in [43]. NeuAc2-3Gal1-4Glc1-1Cer (NeuAc-GM3); NeuGc2-3Gal1-4Glc1-1Cer (NeuGc-GM3); GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer (GM2); NeuAc2-8NeuAc2-3Gal1-4Glc1-1Cer (GD3); Gal1-3GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer (GM1); NeuAc2-3Gal1-3GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer (GD1a); Gal1-3GalNAc1-4(NeuAc2-8NeuAc2-3)Gal1-4Gle1-1Cer (GD1b); NeuAc2-3Gal1-3GalNAc1-4(NeuAc2-8NeuAc2-3) Gal1.-4Glc1-1Cer (GT1b). NeuGc2-3Gal1-4GleNAc1-4Gal1-4Glc1-1Cer (NeuGc-SPG).  相似文献   

17.
Zusammenfassung 45 Eier und 8 Kükenlebern des Kiebitzes aus den Jahren 1984 und 1986 wurden auf -, -, -HCH, HCB, DDT, Dieldrin, Endrin und PCB untersucht. Hohe Konzentrationen an Dieldrin wurden in den Eiern gefunden, während die Lebern von Kiebitzküken geringer belastet waren. Die geringen Konzentrationen der übrigen Pestizide und die mäßige an PCB entsprachen der niedrigen Trophieebene des Kiebitzes. Die Frage, ob die Belastung mit Dieldrin einen Einfluß auf den Rückgang von Kiebitzpopulationen in einigen Gebieten haben könnte, wird kurz diskutiert.
The burden of Dieldrin and other chlorinated hydrocarbons on the Lapwing (Vanellus vanellus)
Summary -, -, -HCH, HCB DDT, Dieldrin, Endrin, and PCB were determined in 45 eggs and 8 livers of young Lapwings in 1984 and 1986. High concentrations of Dieldrin were found in eggs while those in livers of young Lapwings were lower. The low residues of the other pesticides and the moderate ones of PCB are in accordance with the low trophic level of the Lapwing. The probable influence of the Dieldrin burden on the decline of Lapwing populations in several regions is discussed briefly.


Gefördert mit Hilfe von Forschungsmitteln des Landes Niedersachsen  相似文献   

18.
Structures of the Asn linked oligosaccharides of quail egg-yolk immunoglobulin (IgY) were determined in this study. Asn linked oligosaccharides were cleaved from IgY by hydrazinolysis and labelled withp-aminobenzoic acid ethyl ester (ABEE) afterN-acetylation. The ABEE labelled oligosaccharides were then fractionated by a combination of Concanavalin A-agarose column chromatography and anion exchange, normal phase and reversed phase HPLC before their structures were determined by sequential exoglycosidase digestion, methylation analysis, HPLC, and 500 MHz1H-NMR spectroscopy. Quail IgY contained only neutral oligosaccharides of the following categories: the glucosylated oligomannose type (0.6%, Glc1-3Glc1-3Man9GlcNAc2; 35.6%, Glc1-3Man7–9GlcNAc2). oligomannose type (15.0%, with the structure Man5–9GlcNAc2) and biantennary complex type with core structures of-Man1-3(-Man1-6)Man1-4GlcNAc1-4GlcNAc (9.9%),-Man1-3(GlcNAc1-4)(-Man1-6)Man1-4GlcNAc1-4GlcNAc (25.1%) and-Man1-3(GlcNAc1-4)(-Man1-6)Man1-4GlcNAc1-4(Fuc1-6)GlcNAc (11.4%). Although never found in mammalian proteins, glucosylated oligosaccharides (Glc1Man7–9GlcNAc2) have been located previously in hen IgY.Abbreviations IgG, IgM, IgA, IgY immunoglobulin G, M, A and Y, respectively - ABEE p-aminobenzoic acid ethyl ester  相似文献   

19.
Summary Detailed restriction enzyme analysis of the DNA from a Chinese female showed that one of her chromosomes had a >17.5 kb deletion of DNA, including the , 2, and 1 globin genes, which is present in many Southeast Asians with an -thalassemia-1 chromosome. Her normal chromosome had the expected cluster of -like globin genes (5----2-1-3), but the segment of DNA between the two globin genes was elongated by some 0.5–0.7 kb. Analyses of various restriction sites suggested that this normal variant of the human globin gene complex is due to a crossover between a normal chromosome with () and a chromosome with an -thalassemia-2 (–3.7) and an -21-hybrid gene.  相似文献   

20.
Zusammenfassung Der Eilegeapparat mit drei Paar Gonapophysen wind als der ursprünglichste angesehen und vollständiger Eilegeapparat genannt; alle Typen mit weniger als drei Gonapophysenpaaren sind von ihm durch Rudimentation abzuleiten und werden als unvollständiger Eilegeapparat zusammengefaßt.Am vollstandigen Eilegeapparat sind seine Teile durch Gelenke und Muskeln beweglich, am unvollstandigen sind sie starr ; Gelenke und Legemuskeln fehlen. Die fur die Eiablage wichtigen Gelenke und Muskeln werden beschrieben.Die Entwicklung des vollstandigen Eilegeapparates erfolgt bei der Larve in der Reihenfolge, daß zuerst die Gon. laterales, hierauf die mediales und zuletzt die anteriores ausgebildet werden. Die Rudimentation des unvollstandigen geschieht in der gleichen Reihenfolge, indem zuerst die Gon. laterales und als letzte die anteriores zurück-gebildet worden.Die Eiablage erfolgt beim vollstandigen Eilegeapparat primär exophytisch durch Ablage auf dem Boden oder endophytisch durch Einstechen in Pflanzengewebe, beim unvollstandigen Eilegeapparat exophytisch durch Ablage in das Wasser.Es wind angenommen, daß die primär exophytische Ablageart die ursprünglichste ist und alle anderen von ihr abzuleiten sind.Die endophytische Ablage entwickelt an den Gonapophysen verschiedene Anpassungen, die exophytische führt zu ihrer Rudimentation.Anpassungen an die endophytische Ablage sind Verkürzung der Gonapophysen, Entwicklung eines Tastapparates (Styli), eines Schneide-apparate (Gon. mediales), einer Legeröhre (Gon. anteriores) und einer Stützkante an den Gon. laterales, Ablage in Gonaphysenstellung, oder am 10. Sternit, Ablage in Sternitstellung.Ablage in Gonapophysenstellung beansprucht die Gon. laterales und führt bei Ablage in ein Substrat von zunehmender Härte - sie erfolgt in extremen Fallen in Baumstämme — zu verschiedenen Modifikationen ; Ablage in Sternitstellung läßt die Gon. laterales unbeansprucht und könnte bei Ablage in ein Substrat von abnehmender Härte — sie erfolgt in extremen Fallen in Schlamm — zu Rudimentation der Gon. laterales und exophytischer Ablage in das Wasser überleiten.Der unvollständige Eilegeapparat zeigt eine große Formenmannigfaltigkeit, die sich aber auf zwei Grundtypen, einem mit zwei Paar Gonapophysen — es fehlen die Gon. laterales — und einem mit einem Gonapophysenpaar, der Scheidenklappe, einem Rudiment der Gon. anteriores, zurückführen lassen.Der Zweigonapophysentypus ist bei verschiedenen Gruppen erhalten; bei den Cordulegasterinae ist er morphologisch einheitlich, was einen Stillstand des Rudimentationsprozesses andeutet, und an eine bestimmte Eiablageart angepaßt; bei den anderen Gruppen ist er morphologisch sehr verschieden, wobei es sich wohl um verschiedene Rudimentationsstufen handelt, und fur die Eiablage funktionslos geworden.Der Scheidenklappentypus findet sich bei den Gomphidae, Corduliidae und Libellulidae. Ursprünglichere Formen zeigen längere, höher entwickelte, kürzere Scheidenklappen. Bei vielen Arten ist die Scheidenk1appe restlos rudimentiert. Ihre Rolle für die Eiablage ist fraglich, vielleicht nur sinnesphysiologischer Art. Mechanisch zu deutende Formen (Spitzhammerbildung) kommen vor und sind gelegentlich mit Eiablage auf dem Boden verbunden, was als Anklänge an eine primär exophytische Ablage gedeutet wird.Bei den Libellulidae werden vereinzelt sekundäre Apparate aus neuen Elementen entwickelt.Die Eizahl ist bei Formen mit vollständigem Eilegeapparat höher als bei Formen mit ,unvollständigem und bei den Corduliidae und Libellulidae am höchsten.Die morphologische Vielfalt der Eilegeapparate ist das Ergebnis von zwei Verhaltensänderungen, dem Üborgang der Imagines zu einer Ablage durch Einstechen in Pflanzengewebe und dem Übergang der Larven zum Leben im Wasser. Diese Änderungen wurden von den einzelnen Gruppen auf verschiedene Weise und in verschiedenem Ausmaße vollzogen und ließen eine Unzahl von morphologischen Typen entstehen.Das Bestreben, die Eier möglichst nahe dem Wasser abzulegen, führte jene Gruppen, die nicht oder nicht zu weit an die Ablage in Pflanzengewebe angepaßt waren, zur Ablage in das Wasser. Diese Ab lageart führte zur Rudimentation der Gonapophysen und ließ möglicherweise neue, der neuen Ablageart angepaßte Apparate entstehen.Die Rudimentation der Gonapophysen ermöglichte eine Erhöhung der Eizahl und führte these Gruppen zur Besiedlung von neuen Lebensräumen und damit zu ihrer heute dominierenden Stellung innerhalb der Ordnung.  相似文献   

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