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51.
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Pyrroloquinoline quinone-dependent quinoprotein alcohol dehydrogenases (PQQ-ADH) require ammonia or primary amines as activators in in vitro assays with artificial electron acceptors. We found that PQQ-ADH from Pseudomonas putida KT2440 (PpADH) was activated by various primary amines, di-methylamine, and tri-methylamine. The alcohol oxidation activity of PpADH was strongly enhanced and the affinity for substrates was also improved by pentylamine as an activator.  相似文献   
53.
The discovery that anisomycin showed plant growth-regulating activity led to the investigation of compounds having p-methoxyphenyl group; the p-anisole derivatives. 4-Methoxydiphenylmethanes and related compounds inhibited the growth of both shoots and roots in test plants. Growth-inhibitory activity in the series of 4-methoxydiphenylmethanes was lowered by an increase in the electron donating or withdrawing ability of the substituent and was parabolically dependent on the Hammett’s σ. Selective actions of these compounds in their growth inhibition are discussed based on correlations between their activities against barnyard grass and other test plants.

Some 4-methoxydiphenylmethanes induced chlorosis, a disturbance in phototropism or geotropism, and root hypertrophy.  相似文献   
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Pituitary adenylate cyclase-activating peptide (PACAP) is widely distributed throughout the nervous system. PACAP not only acts as a neurotransmitter but also elicits a broad spectrum of biological action via the PACAP-specific receptor, PAC1. However, no studies have investigated PACAP and PAC1 in the periodontal ligament (PDL), so we aimed to perform this investigation in rats after tooth luxation. In the PDL of an intact first molar, there are few osteoclasts and osteoblasts. However, at days 3 and 5 after luxation, large PAC1-positive cells, thought to be osteoclasts because of their expression of the osteoclast marker, tartrate-resistant acid phosphatase, were detected in appreciable numbers. Osteoblast numbers increased dramatically on day 7 after luxation, and PAC1-positive mononuclear small cells were increased at day 14, many of which expressed the osteoblast marker, alkaline phosphatase. PACAP-positive nerve fibers were rarely detected in the PDL of intact first molars, but were increasingly evident at this site on days 5 and 7 after luxation. Double-immunofluorescence analysis demonstrated the relationship between PACAP-positive nerve fibers and PAC1-positive osteoclasts/-blasts in the PDL. At 5 days after luxation, PACAP-positive nerve fibers appeared in close proximity to PAC1-positive osteoclasts. At 7 days after luxation, PACAP-positive nerve fibers appeared in close proximity to PAC1-positive osteoblasts. These results suggest that PACAP may have effects on osteoclasts and osteoblasts in the PDL after tooth luxation and thus regulate bone remodeling after these types of injury.  相似文献   
56.
The elucidation of the biological role of glycan is one of the most important issues to be resolved following the genome project. RNA interference is becoming an efficient reverse genetic tool for studying gene function in model organisms, including C.elegans and Drosophila melanogaster. Our molecular evolutionary study has shown that a prototype of glycosyltransferases, which synthesize a variety of glycan structures in the Golgi apparatus, was conserved between mammals and Drosophila. For analyses of the basic physiological functions of glycans, we established the Drosophila inducible RNAi knockdown system and applied it to one glycosyltransferase and one transporter, proteoglycan UDP-galactose: beta-xylose beta1,4galactosyltransferase I and the PAPS-transporter, respectively. If on the silencing of each gene induced ubiquitously under the control of a cytoplasmic actin promoter, the RNAi knockdown fly died, then the protein was indispensable for life. The expression of the target gene was disrupted specifically and the degree of interference was well correlated with the phenotype. The inducible RNAi knockdown fly obtained using the GAL4-UAS system will pave the way for the functional analysis of glycans.  相似文献   
57.
Eighteen strains of obligately oligotrophic bacteria that grow in a medium containing 1 mg of organic carbon per liter and do not grow in a rich medium (5 g/liter of nutrient) were isolated as dominant organisms from the oligotrophic water of Lake Biwa. The growth properties of these, especially of five strains, were examined. The maximum cell yield ranged from 8.5×104/ml to 2.3×106/ml, and their doubling times ranged from 6.6/h to 11.8/h in LT10–4 medium (0.5 mg trypticase and 0.05 mg yeast extract in 1 liter of filtered and aged lake water). They also showed good growth in lake water medium without adding nutrients. The optimum concentrations for their growth were 5 mg/1, 5–50 mg/1, 50 mg/1, or 500 mg/1, depending on the strains. They utilized glutamate, glycine, serine, and glycolate, but not acetate, proline, or leucine. Several properties were examined. Their growth properties were very different from those of oligotrophs or oligocarbophiles isolated by other researchers.  相似文献   
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Naked filose and reticulose protozoa were long lumped as proteomyxids or left outside higher groups. We cultivated eight naked filose or reticulose strains, did light microscopy, 18S rDNA sequencing and phylogeny (showing all are Cercozoa), and sequenced 80 environmental 18S-types. Filose species belong in subphylum Filosa and reticulose ones in subphylum Endomyxa, making proteomyxids polyphyletic. We therefore transfer the classically mainly reticulose Proteomyxidea to Endomyxa, removing evident filosans as new class Granofilosea (including Desmothoracida, Acinetactis and new heliomonad family Heliomorphidae (new genus Heliomorpha (=Dimorpha)). Five new species of Limnofila gen. n. (L. mylnikovi; L. anglica; L. longa; L. oxoniensis; L. borokensis, previously misidentified as Biomyxa (=Gymnophrys) cometa) form a large freshwater clade (new order Limnofilida). Mesofila limnetica gen., sp. n. and Nanofila marina gen., sp. n. group separately in Granofilosea (Cryptofilida ord. n.). In Endomyxa, a new genus of reticulose proteomyxids (Filoreta marina, F. japonica, F. turcica spp. n., F. (=Corallomyxa) tenera comb. n.) forms a clade (Reticulosida) related to Gromiidea/Ascetosporea. Platyreta germanica gen., sp. n. and Arachnula impatiens are related vampyrellids (Aconchulinida) within a large clade beside Phytomyxea. Biomyxidae and Rhizoplasmidae fam. n. remain incertae sedis within Proteomyxidea. Gymnophrydium and Borkovia are revised. The reticulose Corallomyxa are unlike Filoreta and possibly Amoebozoa, not Cercozoa.  相似文献   
60.
Expression of prolactin gene in incubating hens   总被引:2,自引:0,他引:2  
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