巻号一覧
107 巻, 6 号
選択された号の論文の18件中1～18を表示しています
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Mitsuhiro Itaya, Isamu Yamaguchi, Kaori Kobayashi, Toyoshige Endo, Ter ...1990 年 107 巻 6 号 p. 799-801
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーThe blasticidin S resistance gene (bsr), originally isolated from Bacillus cereus, was studied in Bacillus subtilis. It was found that a 617 by fragment including the intact bsr gene and its 5' flanking region could confer BS resistance on B. subtilis when integrated in its chromosome, even in a single copy state. The construction of a bsr gene cassette and its practical application as a novel selection marker for B. subtilis are reported.抄録全体を表示PDF形式でダウンロード (283K) -
Hirokazu Sato, Takashi Yamauchi, Hitoshi Fujisawa1990 年 107 巻 6 号 p. 802-809
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーA calmodulin-dependent protein kinase has been purified from rat spleen. The enzyme showed a remarkably similar substrate specificity and kinetic parameters to those of rat brain calmodulin-dependent protein kinase II, and exhibited cross-reactivity to a mono-clonal antibody against rat brain calmodulin-dependent protein kinase II, indicating that the enzyme might be a calmodulin-dependent protein kinase II isozyme. The sedimentation coefficient was 13.9S, the Stokes radius was 67A, and the molecular weight was calculated to be 380, 000. The purified enzyme gave five polypeptides bands, corresponding to molecular weights of 51, 000, 50, 000, 21, 000, 20, 000, and 18, 000, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Incubation of the purified enzyme with Ca2+, calmodulin, and ATP under phosphorylating conditions induced the phosphorylation of all five polypeptides. When the logarithm of the velocity of the phosphorylation was plotted against the logarithm of the enzyme concentration (van't Hoff plot), slopes of 0.89, 0.94, and 1.1 were obtained for the phosphorylation of the 50/51-kDa doublet, 20/21-kDa doublet, and 18-kDa polypeptide, respectively. These results indicate that the phosphorylation of the five polypeptides is an intramolecular process, and further indicate that all five polypeptides are subunits of this enzyme. Of the five polypeptides, only the 50- and 51-kDa polypeptides bound to [125I] calmodulin, the other polypeptides not binding to it. A number of isozymic forms of calmodulin-dependent protein kinase II so far demonstrated in various tissues are known to be composed of subunits with molecular weights of 50, 000 to 60, 000 which can bind to calmodulin. Thus, a new type of calmodulin-dependent protein kinase II was demonstrated in the present study.抄録全体を表示PDF形式でダウンロード (3056K) -
Shuhei Zenno, Masahira Hattori, Yoshio Misumi, Toshitsugu Yubisui, Yos ...1990 年 107 巻 6 号 p. 810-816
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーRat cDNA encoding NADH-cytochrome b5 reductase (b5R) was isolated from a rat liver cDNA library using a human b5R cDNA as a probe. The cDNA was 1, 905 nucleotides long, consisting of a 5'-terminal untranslated region of 38 nucleotides long, an open reading frame region of 903 nucleotides long encoding 301 amino acid residues, a 3'-terminal untranslated region of 952 nucleotide long, and a poly(A) tail. The amino acid sequence deduced from the cDNA sequence indicated that the rat b5R precursor contained only one extra amino acid (Met) residue at the N terminus, in comparison with the mature form of the enzyme, suggesting that no extra leader peptide is required for translocation of the enzyme to the microsome membrane. Genomic DNA encoding the b5R gene was isolated from rat genomic DNA libraries. The gene was about 17 kb long, and consisted of nine exons and eight introns. The junction between the membrane-binding and catalytic domains of the enzyme was found in the middle of exon 2, suggesting the possibility that the two forms of the enzyme, namely the membrane-bound and soluble forms, are generated through post-translational processing. The possible promoter region of the gene contained no TATA box but four GC box sequences (GGGCGG and CCGCCC), representing potential binding sites for the transcription factor, SP1. The b5R gene seems to have structural characteristics of a house-keeping gene.抄録全体を表示PDF形式でダウンロード (1827K) -
Tapani Hyvönen, Alex R. Khomutov, Radii M. Khomutov, Seppo Lapinj ...1990 年 107 巻 6 号 p. 817-820
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーThe uptake, catabolism, and release of 3H-labeled 1-aminooxy-3-aminopropane, a new putrescine analog shown to be a potent polyamine antimetabolite, into and from baby hamster kidney cells (BHK21/C13) were studied. The results show that [3H]-1-aminooxy-3-aminopropane (APA) is not concentrated in the cell, does not compete with polyamines for transport and reveals no difference in uptake between polyamine-depleted and control cells. After a 12-h culture, 60% of APA was recovered intact in the culture media. At this time point, only 30% of the intracellular radioactivity was intact APA, showing that the drug is catabolized in the cells. This intracellular ratio persisted throughout the 4-day culture period. The metabolites of APA were not characterized further. The results indicate that the drug is not recognized as a polyamine by the cells and does not replace or interfere with the polyamines in cellular functions. Thus, its potent affinity to ornithine decarbox-ylase and spermidine synthase is likely to be due to close structural similarity with the intermediates formed in these reactions. This has implications for the mechanisms involved.抄録全体を表示PDF形式でダウンロード (446K) -
Alice Miranda Teno, Carlos Alberto Vieira, Marcelo Matos Santoro, Arma ...1990 年 107 巻 6 号 p. 821-825
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーCrotamine, a basic neurotoxic protein, was isolated from the venom of the Southern Brazillian rattlesnake (Crotalus durissus terrificus) by gel filtration. The isolated protein showed a single band on PAGE at pH 4.5 and 7% (w/v) gel concentration, but two or more bands at 14% gel concentration, even in the presence of 4 M urea. After reduction and carboxymethylation, however, a single band was again detected. SDS-PAGE as well as ultracentrifugal analysis of the native (NC) and of the reduced and carboxymethylated (RCC) crotamine revealed a molecular weight of 4, 500-5, 000 for RCC and 9, 000-10, 000 for NC. Both components of a two-band crotamine preparation were isolated by preparative PAGE and characterized. Their particular electrophoretic mobility was retained. Their amino acid composition, N-terminal residue, and apparent toxicity were the same as those of the original sample. It was concluded that crotamine is able to form a dimer of 9, 760 Da with two identical polypeptide chains crosslinked by interchain disulfide bonds and a shape not very far from spherical, which covalently binds extra subunits of 4, 880 Da each.抄録全体を表示PDF形式でダウンロード (2319K) -
Nobuyuki Koga, Noritaka Ariyoshi, Hiroshi Nakashima, Hidetoshi Yoshimu ...1990 年 107 巻 6 号 p. 826-833
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーTwo forms of cytochrome P-450 (P-450) from liver microsomes of hamsters treated with 2, 3, 4, 7, 8-pentachlorodibenzofuran (PenCDF), which possesses the potent acute toxicity and 3-methylcholanthrene (MC)-type inducing ability of liver microsomal monooxygenases in animals, were purified and characterized. These P-450 forms, designated as hamster P-450H and hamster P-450L, had the molecular masses of 52 and 50 kDa, respectively, and showed the absorption maximum of CO-reduced difference spectra at 446 nm. The absolute spectra of their oxidized forms indicated that hamster P-450H was in high-spin state and hamster P-450L was in low-spin state. A part of PenCDF injected into hamster was tightly bound to purified hamster P-450H at a ratio of 0.107 nmol PenCDF/nmol P-450. In a reconstituted system, both hamster P-450H and hamster P-450L showed relatively low catalytic activities for 3-hydroxylation of benzo [a]pyrene and O-deethylations of both 7-ethoxyresorufin and 7-ethoxycoumarin, while they both catalyzed 7α- and 2α-hydroxylations of testosterone effectively to a similar extent. Addition of cytochrome b5 to a reconstituted system accelerated the formation of 7α-hydroxytestosterone 5.3-fold with hamster P-450L and 2.2-fold with hamster P-450H. In addition, hamster P-450H catalyzed estradiol 2-hydroxylation at a high rate but hamster P-450L did not. Immunochemical studies using antiserum to each P-450 form revealed that hamster P-450H and hamster P-450L differ from each other and comprise about 61 and 31% of the total P-450 in PenCDF-treated microsomes, respectively, indicating that these are PenCDF-inducible and major forms of P-450 in PenCDF-treated hamsters. Similarly to PenCDF, inducers such as MC, 3, 4, 5, 3', 4'-pentachlorobiphenyl, and isosafrole also preferentially induced hamster P-450H rather than hamster P-450L, but β-naphthoflavone preferentially increased hamster P-450L. Phenobarbital, pregnenolone 16α-carbonitrile and ethanol did not affect the contents of these forms at all. Analyses of NH2-terminal amino acid sequences demonstrated that hamster P-450H and hamster P-450L correspond to rat P-450d and rat P-450a, respectively.抄録全体を表示PDF形式でダウンロード (2676K) -
Eiji Ohmori, Tetsuya Fukui, Noriaki Imanishi, Kimio Yatsunami, Atsushi ...1990 年 107 巻 6 号 p. 834-839
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーHistidine decarboxylase was purified from mouse mastocytoma P-815 cells to electropho-retic homogeneity by ammonium sulfate fractionation, dialyses at pH 7.5 and 6.0, chroma-tographies on DEAE-Sepharose CL-6B, Phenyl-Sepharose CL-4B and Hydroxylapatite, Phenyl-Superose HPLC, Mono Q HPLC, and Diol-200 gel filtration HPLC. Under the assay conditions used, the pure enzyme exhibited a specific activity of 800 nmol/min/mg, which constituted 12, 500-fold purification compared to the crude extract, with a 7% yield. The two-step dialysis turned out to be essential for removing the factor(s) which interfered with the enzyme purification. The optimum pH for the enzyme reaction was 6.6 and the isoelectric point of the enzyme was pH 5.4. The molecular mass of the enzyme was found to be approximately 53 kDa on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, 110 kDa on gel filtration, and 115 kDa on polyacrylamide gradient gel electrophoresis in the absence of sodium dodecyl sulfate. The Km value for histidine was estimated to be 0.26 mM at pH 6.8.抄録全体を表示PDF形式でダウンロード (769K) -
Hideyu Ono, Syozo Tuboi1990 年 107 巻 6 号 p. 840-845
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーThe receptor protein for the mitochondrial protein precursor synthesized in the cytosol was extensively purified from the mitochondrial membrane fraction by affinity column chromatography using a synthetic peptide containing the extrapeptide of ornithine aminotransferase as a ligand. The purified fraction contained two major proteins with molecular masses of 52 and 29kDa. Of these proteins, only the 29kDa protein bound to the extra-peptide of ornithine aminotransferase. Furthermore, anti-29kDa protein Fab fragments inhibited the import of pre-ornithine aminotransferase into mitochondria, suggesting that the 29kDa protein plays an essential role in the process of import of the mitochondrial protein precursor.抄録全体を表示PDF形式でダウンロード (3038K) -
Yasushi Sako, Satoshi B. Sato, Shun-ichi Ohnishi1990 年 107 巻 6 号 p. 846-853
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーSubpopulations of endosomes generated at different stages of the endocytic pathway were isolated by a high-gradient magnetic separation followed by a Percoll density gradient centrifugation. Rat livers were perfused for 5 min with asialoganglioside (ASG)-containing ferrite particles and chased at 37°C. At various times after the internalization, the endocytic vesicles containing ferrite particles were isolated by the magnetic separation. Isolated fractions contained endosomes until 15-min perfusion, after which most of the particles were transported to lysosomes. The endosomal fractions isolated after the 5- or 15-min perfusions were further analyzed by 30% Percoll density gradient centrifugation. The endosomes after 5-min perfusion showed peaks around the density of 1.05g/ml (peak I) and 1.07g/ml (peak Is), both of which contained asialoglycoprotein receptors. In the 15-min perfusion, another peak of endosomes (peak II) was observed at the higher density of 1.09g/ml without the receptors, in addition to peak I. These endosomes had their own character-istic proteins. Some proteins were common in the subgroups of endosomes. These results suggest that the endosome Icontaining the ligands and the receptors was first produced after endocytosis and, through the endosome Is, was scissioned into the endosome IIcontaining the ligands. The endosome IIwas then fused with primary lysosomes for proteolytic cleavage of ligands.抄録全体を表示PDF形式でダウンロード (3486K) -
Kiyotaka Hatsuzawa, Won-Sin Kim, Kazuo Murakami, Kazuhisa Nakayama1990 年 107 巻 6 号 p. 854-857
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーRenin is produced from a larger, inactive precursor, prorenin, by endoproteolytic removal of the amino-terminal prosegment. In this study, we have transfected Chinese hamster ovary cells with the expression plasmid of mouse Ren 2 preprorenin, and have purified mouse Ren 2 prorenin from the incubation medium of these cells by DEAE-Toyopearl chromatography, Blue-Toyopearl chromatography, and isoelectric focusing. Prorenin thus purified has a molecular mass of 42 kDa as determined by SDS-PAGE and an isoelectric point of 6.5. Amino-terminal sequencing has demonstrated that the purified prorenin has the amino-terminus predicted from the nucleotide sequence of mouse Ren 2 preprorenin cDNA.抄録全体を表示PDF形式でダウンロード (1019K) -
Ryuzo Sakakibara, Shuichi Miyazaki, Masatsune Ishiguro1990 年 107 巻 6 号 p. 858-862
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーHuman chorionic gonadotropin (hCG) is a glycoprotein hormone composed of two dissimialr subunits (α and β) and normally excreted in urine of pregnant women. An uncommon β-subunit of hCG was purified from fresh early normal pregnancy urine by Sepralyte C8 resin adsorption, Sephadex G-100 column chromatography, and reverse-phase HPLC. SDS-PAGE under non-reducing conditions showed that the apparent molecular weight (39, 000) of this β-subunit was extremely similar to that of the native β-subunit, which is known to consist of 145 amino acid residues and carbohydrates. However, SDS-PAGE, under reducing conditions, resulted in two bands with apparent molecular weights of 22, 000 and 18, 000, indicating that it consisted of two peptide fragments connected with disulfide bridge(s). These two peptide fragments, separated and purified from the reduced and carboxymethylated protein, were subjected to amino acid and N-terminal sequence analyses. It was found that this 8-subunit consisted of two polypeptide chains composed of residues 1-47 disulfide-bridged to residues 48-145 of the β-subunit, which may be produced by nicking of the β-subunit at the one site (Gly47-Val48). This β-subunit was termed a nicked β-subunit of hCG (N-hCGβ). It was also found that N-hCGβ was present in urine as an aβ dimer, indicating that an intrachain nicking of this site in the β-subunit does not inhibit aβ dimer formation. However, this nick in the β-subunit did reduce a hormonal activity (the stimulatory effect on testosterone production in rat Leydig cells) of hCG, since the activity of hCG reconstituted with N-hCGβand intact α-subunit was significantly lower than that of intact hCG.抄録全体を表示PDF形式でダウンロード (2467K) -
Emiko Shinagawa, Kazunobu Matsushita, Osao Adachi, Minoru Ameyama1990 年 107 巻 6 号 p. 863-867
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーGluconobacter suboxydans contains membrane-bound D-glucose and alcohol dehydrogenases (GDH and ADH) as the primary dehydrogenases in the respiratory chain. These enzymes are known to be quinoproteins having pyrroloquinoline quinone as the prosthetic group. GDH reduces an artificial electron acceptor, ferricyanide, in the membrane, but notafter solubilization with Triton X-100, while ADH can react with the electron acceptor even after solubilization and further purification. In this study, it has been shown that the ferricyanide reductase activity of GDH is restored by adding the supernatant solubilized with Triton X-100 to the residue, and also by incorporation of purified ADH into the membranes of an ADH-deficient strain, G. suboxydans var. α. In addition, the ferricyanide reductase activity of GDH was reconstituted in proteoliposomes from GDH, ADH, and ubiquinone-10. Thus, the results indicated that the electron transfer from GDH to ferricyanide was mediated by ubiquinone and ADH. The data also suggest that GDH and ADH transfer electrons mutually via ubiquinone in the respiratory chain.抄録全体を表示PDF形式でダウンロード (621K) -
Takashi Terabayashi, Tadao Ogawa, Yasuhiro Kawanishi1990 年 107 巻 6 号 p. 868-871
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーTwo novel ganglioside lactones were isolated from the brain of Bryde's whale (Balaenoptera edeni) and characterized. These gangliosides migrated above CM4 and were designat-ed M4-1 and M4-2 in the order of location from the bottom of the TLC plate. These gangliosides were converted to GM4 by mild alkali treatment. Although M4-1 and M4-2 contained 1 mol each of N-acetylneuraminic acid and galactose, they behaved as neutral lipids on ion-exchange chromatography. Inner ester linkages were found in these gan-gliosides by secondary ion mass spectrometry and infrared spectroscopy. Two-dimensional J-correlated proton NMR spectra revealed that an inner ester linkage was formed in M4-1 between the sialic acid carboxyl group and the C-4 hydroxyl group of the galactosyl residue and another inner ester linkage was formed in M4-2 between the sialic acid carboxyl group and the C-2 hydroxyl group of galactose.抄録全体を表示PDF形式でダウンロード (2602K) -
Kaoru Inoue, Hitoshi Sohma, Fumi Morita1990 年 107 巻 6 号 p. 872-878
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーCa2+-dependent protein phosphatase was purified from scallop adductor smooth muscle by a combination of DEAE-Toyopearl 650S ion exchange chromatographies and gel filtration on Sephacryl S-300. The phosphatase consisted of two subunits having molecular weights of 60 and 19 kDa. Phosphorylated regulatory light chain-a (RLC-a) was dephosphorylated by this phosphatase both in free and bound states in myosin prepared from the opaque portion of scallop smooth muscle (opaque myosin). The dephosphorylation was activated by Ca2+. The half maximal activation was at 1μM free Ca2+ in the presence of calmodulin and 7μM free Ca2+ in the absence of calmodulin. Opaque myosin phosphorylated at the heavy chain was not dephosphorylated with this phosphatase. p-Nitrophenyl phosphate was dephosphorylated. In addition to Ca2+, the phosphatase activity for. RLC-a was activated by Mn2+, while p-nitrophenylphosphatase activity was activated by Mg2+ more strongly than by Mn2+. The pH-activity curves showed a maximum at pH 7 in the presence of Mn2+, but at around pH 8 in the presence of Mg2+. This phosphatase is similar to phosphatase 2B or calcineurin. The possible regulatory function of this phosphatase in scallop catch muscle is discussed.抄録全体を表示PDF形式でダウンロード (1731K) -
Yoshiko Narahashi1990 年 107 巻 6 号 p. 879-886
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーThe amino acid sequence of a zinc-carboxypeptidase from S. griseus (Cpase SG) was determined by automated Edman degradation and carboxypeptidase digestion of the S-carboxymethylated protein and by sequence analyses of peptides produced by cyanogen bromide cleavage and by lysyl endopeptidase digestion of the S-carboxymethylated protein. This enzyme is characterized by a uniquely broad substrate specificity which combines the specificities of mammalian Cpase A and Cpase B (J. Biochem. 86, 683-694, 1979). Cpase SG consists of 328 amino acid residues. The amino acid sequence of Cpase SG is partially similar to those of bovine Cpase A and Cpase B (sequence identity, 28-29%). In the sequence of Cpase SG, residues that are functionally important in mammalian Cpase A and Cpase B were all found at the corresponding positions. Residue 255 (according to the numbering system for bovine Cpase A), which, in the other Cpases, contributes to the difference in specificity between Cpase A (Ile-255) and Cpase B (Asp-255), was Asp. However, residue 254 was Ile, in contrast to Ser or Thr in all of the forms of Cpase A and Cpase B examined to date. The increase in hydrophobicity caused by the change at position 254 and the presence of negative charge at position 255 is probably one of the reasons for the broad substrate specificity of Cpase SG.抄録全体を表示PDF形式でダウンロード (848K) -
Yasuo Ogawa, Hikaru Harafuji1990 年 107 巻 6 号 p. 887-893
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーIt has been clarified that ryanodine binds to Ca2+-induced Ca release channels in the open state in sarcoplasmic reticulum. While the pharmacological action of ryanodine is known to be retarded at a low temperature, the Ca-releasing action of caffeine is potentiated at a low temperature. In order to obtain deeper insight into the molecular mechanism underlying Ca-release, the effect of temperature on ryanodine binding to the heavy fraction of sarco-plasmic reticulum (HFSR) from bullfrog skeletal muscle was examined. Although Ca2+ is indispensable for ryanodine binding, Ca2+ alone cannot cause ryanodine binding in a reaction medium of a salt concentration similar to that of the sarcoplasm. In addition to Ca2+, caffeine and/or β, γ-methylene adenosine triphosphate (AMPOPCP) are necessary. [3H]Ryanodine binding at 25°C closely paralleled the Ca release activity in respect of the Ca2+- dependence in the presence of caffeine and/or AMPOPCP, and the effects of inhibitors. A Scatchard plot for ryanodine binding gave a straight linear line, indicating a single class of homogeneous binding sites. At 0°C, the rate of ryanodine binding decreased, Q10, being about 3 on average. The affinity for ryanodine was reduced to about half that at 25°C, with no change in the maximum number of binding sites. The temperature-dependent change in apparent affinity for Ca2+ on ryanodine binding is not always consistent with that in the case of Ca-release activity. The bound ryanodine may be in an occluded state because it did not dissociate for up to 90 h at 0°C. These results indicate that the open state of Ca2+ -induced Ca release channels is requisite for ryanodine binding and that ryanodine binding to the open state is a distinct process. The physicochemical aspects of ryanodine binding are also discussed.抄録全体を表示PDF形式でダウンロード (810K) -
Yasuo Ogawa, Hikaru Harafuji1990 年 107 巻 6 号 p. 894-898
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーWhile many reports have shown that Ca2+ alone causes ryanodine binding to the heavy fraction of the sarcoplasmic reticulum (HFSR), our results demonstrate that caffeine or β, γ-methylene adenosine triphosphate (AMPOPCP) in addition to Ca2+ is necessary for ryanodine binding, although Ca2+ is indispensable for it. While clarifying the reasons for this discrepancy, we found that a high osmolarity of the reaction medium, but not ionic strength, is a crucial factor. In a hypertonic solution containing 1M NaC1, Ca2+ alone causes a sizable extent of ryanodine binding. Caffeine and AMPOPCP independently stimulate it, unlike the case of 0.17M KC1 (or NaC1) medium, in which they show a potentiating interaction. Ryanodine binding in the hypertonic solution was markedly enhanced not only as to the binding rate but also the extent. The Scatchard plot was linear, indicating a single class of homogeneous binding sites. The maximum number of binding sites as well as the affinity was also increased in 1M NaCI-medium. The presence of AMPOPCP and/or caffeine did not affect the magnitudes of them so much, especially that of the affinity, in the hypertonic medium, as in the isotonic medium. The Ca2+ dependence of ryanodine binding in the stimulatory range was similar to that in 0.17M KCl- (or NaC1-) medium. However, the very weakinhibition at high Ca2+ concentrations is in striking contrast to ryanodine binding in the isotonic medium. The stimulation due to a high osmolarity is distinct, as to the mechanism, from that due to AMPOPCP, caffeine, or temperature. The dissociation of [3H] ryanodine bound was also examined under various experimental conditions.抄録全体を表示PDF形式でダウンロード (588K) -
Mutsumi Sugita, Fuyuhiko Inagaki, Hiromi Naito, Taro Hori1990 年 107 巻 6 号 p. 899-903
発行日: 1990年
公開日: 2008/11/18
ジャーナル フリーTwo neutral glycosphingolipids having large straight oligosaccharide chains with eight and nine sugars, provisionally named COS and CNS, were isolated and purified from larvae of the green-bottle fly, Lucilia caesar, as the only two remaining unidentified significant neutral glycolipids in this organism. From the results of sugar analysis, permethylation, negative-ion fast atom bombardment mass spectroscopy (FAB-MS), and 1H-NMR studies, the structures of the two glycolipids are proposed to be: COS, Ga1NAcβ1-3G1cNAcβ1-3Galβ1-3GalNAcαl-4GalNAcβl-4G1cNAcβl-3Manβl-4G1cβl-Cer; and CNS, Galβl-3Ga1NAcβ1-3G1cNAc β1-3Gal β1-3GaINAc α1-4Ga1NAcβ1-4G1cNAcβ1-3Manβ1-4G1cβ1-Cer. The fatty acid and long-chain base compositions of the above glycolipids were very similar, and were dominated by arachidic acid, and tetradeca- and hexadeca-4-sphingenines. The great similarity between the compositions of their ceramide moieties suggests that COS may be a precursor in the glycosylation reaction yielding CNS.抄録全体を表示PDF形式でダウンロード (3478K)
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