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21.
Katsuya Koike Masato Mori Yukishige Ito Yoshiaki Nakahara Tomoya Ogawa 《Glycoconjugate journal》1987,4(2):109-116
The first total synthesis of glycosphingolipids isolated from wheat flour has been achieved in a regio- and stereo-controlled manner.Abbreviations THF
tetrahydrofuran
- DMF
dimethylformamide
Part 53 in the series Synthetic Studies on Cell Surface Glycans 相似文献
22.
S Hamasaki H Hayashidani K Kaneko M Ogawa Y Shigeta 《Journal of wildlife diseases》1989,25(3):401-403
Yersinia pseudotuberculosis was isolated from three specimens of two species of birds, the black-faced bunting (Emberiza spodocephala) and pied wagtail (Motacilla alba), of 528 specimens of birds examined from coastal regions in Japan. The two isolated strains of Y. pseudotuberculosis were identified as serovar 4b and serovar 3. This is the first isolation of Y. pseudotuberculosis from birds in Japan. Yersinia enterocolitica was isolated from three specimens of the pied wagtail, one specimen of the reed bunting (Emberiza schoeniclus) and one specimen of the rustic bunting (Emberiza rustica). Yersinia frederiksenii was isolated from two specimens of the gray-rumped sandpiper (Heteroscelus brevipes). Yersinia intermedia was isolated from one specimen of the pied wagtail. 相似文献
23.
The paratypes of Trebius akajeii Shiino, 1954, originally collected from Dasyatis akajei (Müller & Henle) at Owase, Japan, and the paratypes and newly collected specimens of T. latifurcatus Wilson, 1921, previously collected from Urolophus and Myliobatis at Venice, California, are redescribed. New host records for T. latifurcatus are: Torpedo californica Ayres, Squatina californica Ayres, Rhinobatos productus (Ayres), Platyrhinoides triseriata (Jordan & Gilbert), Raja inornata (Jordan & Gilbert) and Gymnura marmorata (Cooper). A new species, Trebius heterodonti, is described from the horn shark Heterodontus francisci (Girard) collected from southern California waters. These three species of Trebius are apparently closely related to each other. Diagnostic characters of the species are provided along with a discussion on the taxonomic value of selected features. 相似文献
24.
25.
The fluorescent body (F-body) was identified with quinacrine mustard (Q-M) staining in spermatozoon and lymphocyte of canine. Well washed sperm suspension was treated with protease (125 mg/ml) or dispase (2000p. u./ml) and staining with Q-M (final dilution 50 micrograms/ml) for 15 min to 24 hr at 37 degrees C. The lymphocyte cultures from whole blood were prepared as routine human investigation. The chromosomal preparation made by air dry method was stained with Q-M (final dilution 0.5 to 50 micrograms/ml) after pretreatment of enzyme digestion. The examination using a reflected fluorescent microscope revealed that the same F-body in human was present in both spermatozoon (20.1-39.7%) and interphase of lymphocyte (0.37.2%) of male origin. 相似文献
26.
Cloning of the Membrane-Bound Aldehyde Dehydrogenase Gene of Acetobacter polyoxogenes and Improvement of Acetic Acid Production by Use of the Cloned Gene 总被引:11,自引:2,他引:9
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Masahiro Fukaya Kenji Tayama Toshimi Tamaki Haruko Tagami Hajime Okumura Yoshiya Kawamura Teruhiko Beppu 《Applied microbiology》1989,55(1):171-176
A genomic clone bank of Acetobacter polyoxogenes NBI1028 constructed in Escherichia coli by use of the expression vector pUC18 was screened with antibody raised against membrane-bound aldehyde dehydrogenase (ALDH; 75 kilodaltons [kDa]) from A. polyoxogenes NBI1028. A clone that synthesized a 41-kDa protein cross-reactive with anti-ALDH antibody was isolated. For cloning of the full-length ALDH structural gene, a cosmid gene bank was screened by Southern blot hybridization with the cloned DNA as a probe, and subcloning from the positive cosmid clone was performed with shuttle vector pMV24. Plasmid pAL25, containing the full-length ALDH structural gene, was isolated and expressed in both E. coli and Acetobacter aceti to produce a fused protein (78 kDa) with a short NH2-terminal β-galactosidase peptide. pAL25 conferred ALDH production on a mutant of A. aceti lacking the enzyme activity. Transformation of A. aceti subsp. xylinum NBI2099 with pAL25 caused 2- and 1.4-fold increases in the production rate and in the maximum concentration of acetic acid in submerged fermentation, respectively. 相似文献
27.
Molecular cloning and nucleotide sequence of human pancreatic prechymotrypsinogen cDNA 总被引:4,自引:0,他引:4
N Tomita Y Izumoto A Horii S Doi H Yokouchi M Ogawa T Mori K Matsubara 《Biochemical and biophysical research communications》1989,158(2):569-575
The cDNA clone encoding human prechymotrypsinogen was isolated from a human pancreas cDNA library and its nucleotide sequence was determined. The sequence consists of a 16 bp 5' non-coding region, a 789 bp amino acid coding region and a 60 bp 3' non-coding region. The predicted product consists of 263 amino acids, including 18 amino acids for a signal peptide and 15 amino acids possible for an activation peptide. Southern blot analyses using the cloned cDNA as a probe revealed that human genomic DNA carries at least two genes that are related to chymotrypsinogen. 相似文献
28.
The growth inhibitor of African green monkey (BSC-1) cells is transforming growth factors beta 1 and beta 2 总被引:1,自引:0,他引:1
The growth inhibitory activity in conditioned medium of African green monkey kidney epithelial (BSC-1) cells that has been shown to arise, at least in part, from transforming growth factor beta 2 (TGF-beta 2) [Hanks, S. K., Armour, R., Baldwin, J. H., Maldonado, F., Spiess, J., & Holley, R. W. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 79-82] was tested for growth inhibitory activity prior to and following acidification. Similar to TGF-beta 1 from human platelets, the inhibitory activity from BSC-1 cells demonstrated an 8-10-fold stimulation following acidification, showing that the activity was secreted from the cells in latent form. Conditioned medium from BSC-1 cells was collected, acidified, and fractionated by procedures that separate TGF-beta 1 and -2. Biological activity was assayed by using the BSC-1 cell proliferation assay. Two active proteins with properties similar to known TGF-beta 1 and TGF-beta 2 were identified. Identity was confirmed by using immunological and amino acid sequencing techniques. These results were consistent with Northern blot analysis of total BSC-1 RNA, using cDNA probes for TGF-beta 1 and TGF-beta 2, which demonstrated strong signals for both mRNAs. Metabolic labeling in conjunction with two-dimensional gel electrophoresis revealed that the cells secrete approximately 10% TGF-beta 1 and 90% TGF-beta 2. 相似文献
29.
Identification of a novel alpha-amylase by expression of a newly cloned human amy3 cDNA in yeast 总被引:1,自引:0,他引:1
A novel amylase gene (amy3) that differs in nucleotide sequence from salivary amylase gene (amy1) and pancreatic amylase gene (amy2) has been described [Tomita et al., Gene 76 (1989) 11-18], but whether this gene can ever code for an active enzyme has not been shown. We prepared cDNA of this gene from an mRNA obtained from lung carcinoid tissue, and expressed it in Saccharomyces cerevisiae under the control of an acid phosphatase promoter. The product was secreted into culture media, and showed enzymatic activity, demonstrating that this novel alpha-amylase gene (amy3) can code for a functional isozyme. We purified this enzyme, and compared its biological properties with those of salivary and pancreatic human amylases similarly expressed in yeast. We observed that the novel amylase isozyme is more heat-sensitive than others, and that its substrate specificity is different from the other two isozymes. 相似文献
30.
The vascular anatomy ofHelminthostachys zeylanica was examined with special reference to anomalous secondary tissue. Primary xylem development gradually takes place centrifugally. In branched rhizomes with destroyed apices, the vascular cylinder apical to the insertion of branch traces is generally composed of primary xylem, accessory xylem, inner parenchyma of radially arranged cells, outer parenchyma of irregularly arranged cells, and partly crushed phloem, listed in order going outwards. The accessory xylem as well as the inner parenchyma ofHelminthostachys zeylanica is probably secondarily produced, partly to contribute to the branch traces, in a position corresponding to that of secondary vascular tissue developed from a normal cambium inBotrychium sensu lato. It is suggested that although a cambium is lacking inHelminthostachys zeylanica, the secondary vascular tissues are comparable between the genera. The phylogenetic implication of this tissue is discussed. 相似文献