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991.
Transglutaminase 3 (TGase 3), involved in the cross-linking of structural proteins in the epidermis, is activated by limited proteolysis of zymogen into two fragments during keratinocyte differentiation. Using recombinant TGase 3, the N-terminus sequence of the proteolyzed fragment was analyzed. Antibody against the synthetic peptide corresponding to the cleavage site specifically detected the fragment in the mouse forestomach extract. 相似文献
992.
Yoshinaga N Sawada Y Nishida R Kuwahara Y Mori N 《Bioscience, biotechnology, and biochemistry》2003,67(12):2655-2657
Volicitin, [N-(17-hydroxylinolenoyl)-L-glutamine], was identified as an elicitor of plant volatiles from a Spodoptera exigua regurgitant. It has been proposed that gut microbes synthesize volicitin from glutamine, a predominant amino acid component in the insect gut. However, we found that glutamine was not a major component in the regurgitant of Spodoptera litura, although L-glutamine was exclusively incorporated into volicitin by S. litura fed on diets enriched with various amino acids. This selectivity of glutamine as a substrate was not due to a dominant occurrence in the insect gut. 相似文献
993.
Kawaura T Inagaki M Tanaka A Kato M Nishikawa S Kashimura N 《Bioscience, biotechnology, and biochemistry》2003,67(4):869-876
A histidine-tagged G protein of bacteriophage phi X174 (HisG) bound strongly with lipopolysaccharide (LPS) of Escherichia coli C, one of a phi X174-sensitive Ra strain. The dissociation constant, Kd, was measured to be 0.16 +/- 0.04 microM by fluorometric titration. HisG showed slightly less affinity to LPSs of the insensitive Rc and Rd 2 strains having shorter R-core polysaccharide sequences than that of the sensitive Ra strains. The difference between the two types of LPS was demonstrated by CD spectra; LPSs of the sensitive strains increased the signal intensity for beta-sheet, while the insensitive strains decreased it. The chemically degraded LPS derivatives lacking a hydrophobic lipid region showed much less affinity to HisG, indicating the importance of the lipid region of LPS for strong binding with HisG. On the other hand, since the degraded derivatives increased the intensity of CD spectra, the polysaccharide region is thought to contribute to the conformation change of the protein. 相似文献
994.
995.
Kajihara Y Kamiyama D Yamamoto N Sakakibara T Izumi M Hashimoto H 《Carbohydrate research》2004,339(8):1545-1550
We reported the synthesis of beta-D-lactosaminide with a 2-aminopyridyl group that is linked to a glycosyl tether at the reducing end. This fluorescent disaccharide acts as an acceptor for both alpha-(2-->6)- and alpha-(2-->3)-sialyltransferases. In addition, the acceptor ability of this disaccharide was evaluated and compared with that of beta-D-lactosaminide having a dansyl or a 4-methylumbelliferyl group. 相似文献
996.
Kaya M Matsumura K Higashida K Hata Y Kawato A Abe Y Akita O Takaya N Shoun H 《Bioscience, biotechnology, and biochemistry》2004,68(10):2040-2049
We cloned and characterized the gene and cDNA of Aspergillus oryzae cytochrome P450nor (Anor). The Anor gene (nicA; CYP55A5) has a different gene structure from other P450nor genes in that it has an extra intron. There were not only two kinds of mRNA but also two sets of TATA-box and CCAAT-box, and it appears that this gene has two expression patterns, like CYP55A1 of Fusarium oxysporum. A reporter analysis using the uidA gene indicated that gene expression of CYP55A5 was induced under anaerobic conditions, like CYP55A1. When the CYP55A5 gene was overexpressed in A. oryzae, a large amount of active Anor were accumulated as intracellular protein. Anor employed both NADH and NADPH as electron donors for reducing nitric oxide to nitrous oxide. Anor measured the amount of NO generated from 3-(2-Hydroxy-1-(1-methylethyl)-2-nitrosohydrazino)-1-propanamine (NOC5) with a spectrophotometer. The sensitivity was 10 nmol/ml. 相似文献
997.
Hirota A Inaba M Chen YC Abe N Taki S Yano M Kawaii S 《Bioscience, biotechnology, and biochemistry》2004,68(6):1372-1374
We isolated from soybean miso 8-hydroxyglycitein and 6-hydroxydaidzein as DPPH-radical scavengers, and elucidated their chemical structures by mass spectrometric, and (1)H- and (13)C-NMR spectrosopic analyses. These compounds showed DPPH-radical scavenging activity as high as that of alpha-tocopherol, 8-hydroxygenistein and 8-hydroxydaidzein. This is the first report of the isolation of 8-hydroxyglycitein from a natural source. 相似文献
998.
Sasaki Y Takaya N Nakamura A Shoun H 《Bioscience, biotechnology, and biochemistry》2004,68(5):1106-1112
A flavocytochrome protein was isolated from the actinomycete Streptomyces antibioticus. The purified protein contained protoheme and FAD, and its M(r) was estimated to be 52000. The absorption spectra in its resting oxidized, dithionite-reduced, carbon monoxide-bound, and oxygenated (O(2)-bound) forms were characteristic of those of flavohemoglobin (Fhb). The N-terminal amino acid sequence showed high identities to those of other Fhb's. Furthermore, the actinomycete flavocytochrome scavenged nitric oxide in the presence of NADH. These results demonstrated that the flavocytochrome is the first Fhb purified from actinomycetes. The actinomycete Fhb was produced in S. antibioticus cells in large amounts without any external nitric oxide (NO) stress, which is indicative of a physiological function of Fhb other than detoxification of NO. 相似文献
999.
The function of delayed greening in the seedlings of canopy tree species in a lowland tropical rain forest was examined in terms of its potential defensive value against herbivory. To explore the ecological and evolutionary backgrounds for delayed greening, we chose eight sympatric congeneric (Shorea) dipterocarp species that were either normal-greening or delayed-greening species. Expansion and toughening of leaves took approximately 30 days for all species, and did not differ between the normal- and delayed-greening species. The main factors that affected leaf damage during expansion were insect herbivory and fungal infection. Levels of leaf damage were significantly lower for delayed-greening species than for normal-greening species, but proportions of heavily damaged leaves and leaf abscission during expansion did not differ. In addition, no significant difference was found in damage levels on leaves (aged 1–2 months) of naturally occurring seedlings between normal- and delayed-greening species. Therefore, delayed greening may effectively reduce the level of leaf damage in young expanding leaves, but may not necessarily reduce leaf abscission and damage to mature leaves. The existence of delayed greening could not be simply explained by the phylogenetic and ecological backgrounds of the trees. Consequently, delayed greening may have a function in reducing damage during expansion, but more information (such as knowledge of the secondary metabolites involved in this phenomenon) is needed to explain fully why these species exhibit delayed greening. 相似文献
1000.
Proteins induced in rice by auxin and zinc were determined by proteome analysis. Cultured suspension cells of rice were treated with 2,4-dichlorophenoxyacetic acid and ZnSO4 and then proteins were separated by two-dimensional polyacrylamide gel electrophoresis; seven proteins were found to be induced by auxin and zinc. Of these seven, methylmalonate-semialdehyde dehydrogenase (MMSDH) was elevated by treatment with auxin alone. MMSDH was detected in cultured suspension cells, root and leaf sheath, but not in leaf blades. MMSDH responded to auxin and gibberellin, but did not respond to brassinolide and cytokinin. Furthermore, the amount of MMSDH in slr1, a constitutive gibberellin response mutant, was 2-fold that of wild type. MMSDH mRNA and protein were stimulated in root formation induced by auxin and/or zinc over a 4-week period. These results suggest that MMSDH may be necessary for root formation in rice induced by auxin and/or zinc.Abbreviations BA
6-Benzylaminopurine
- BL
Brassinolide
- CBB
Coomassie Brilliant Blue
- 2,4-D
2,4-Dichlorophenoxyacetic acid
- GA
Gibberellic acid
- IAA
Indole-3-acetic acid
- MALDI-TOF MS
Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry
- MMSDH
Methylmalonate-semialdehyde dehydrogenase
- 2D-PAGE
Two-dimensional polyacrylamide gel electrophoresis
- PVDF
Polyvinylidene difluoride 相似文献