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41.
Wolfgang Walkowiak 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1988,164(1):31-41
Summary Male fire-bellied toads,Bombina bombina, are stimulated into calling by conspecific mating calls. They tend to synchronize their activity with other calling individuals, which leads to antiphonal calling. Behavioral physiological experiments revealed the existence of two different auditory filter systems which influence this acoustic behavior. One filter system is tuned to the recognition of conspecific mating calls, the other is part of a circuit that controls an acoustic jamming avoidance reaction. The two filter systems differ in several properties: filter bandwidth, threshold, and time constant. Neurophysiological recordings in the midbrain and the thalamus show that the filter characteristics can be explained by the coding properties of auditory neurons in these two brain nuclei. 相似文献
42.
Wolfgang H. Schwarz Silke Schimming Walter L. Staudenbauer 《Biotechnology letters》1988,10(4):225-230
Summary AClostridium
thermocellum gene directing the synthesis of a thermostable -glucanase was localized on a 1.9-kb DNA fragment by subcloning intoEscherichia
coli plasmid vectors. The enzyme was highly efficient in degrading glucans with alternating -1, 3- and -1,4-linkages such as lichenan and barley glucan. It was also active towards the -1, 3-glucan laminarin, but lacked activity on cellulosic substrates and -glucans. The enzyme was therefore classified as -1, 3-glucanase (laminarinase) and the corresponding gene was designatedlicA. With barley -glucan as substrate the enzyme had a pH optimum around pH 6.5 and a temperature optimum at 65°C. It was stable for several hours at 60°C in the absence of substrate. 相似文献
43.
The redox-enzyme ferredoxin-NADP-oxidoreductase has been shown to be activated by light and inactivated in the dark. This review will summarize recent data concerning the biochemical characterization of the enzyme compared to its in-vivo activation. Further-more the mechanism of this activation process is discussed as a conformational change caused by the light-driven proton gradient.Abbreviations cyt
cytochrome
- fd
ferredoxin
- FNR1
large form of ferredoxin-NADP-oxidoreductase
- FNRox
oxidized FNR
- FNRred
reduced FNR
- FNRs
small form of FNR
- FNRsq
FNR-semiquinone 相似文献
44.
Organisation and expression of a wound/ripening-related small multigene family from tomato 总被引:3,自引:0,他引:3
cDNA clones derived from a ripe tomato fruit cDNA library were used to investigate changes in the abundance of specific mRNAs in ripening fruit and wounded leaves. mRNAs related to one cDNA clone (pTOM 13) were expressed in both situations. This clone was used to identify homologous sequences in a tomato genomic library. Three groups of related clones that hybridised to the pTOM 13 cDNA insert were identified and subcloned into plasmid vectors. Genomic Southern analysis of tomato DNA using gene-specific DNA fragments isolated from the subcloned DNAs indicated that all pTOM 13 closely related genes had been isolated. RNA dot blot analysis with these DNA fragments as probes indicated differential expression of this small multigene family in leaves and fruit. 相似文献
45.
Wolfgang Ahlf 《Applied microbiology and biotechnology》1988,28(4-5):512-513
Summary
Cyanidium caldarium grows in acid water obtained from a bacterial leaching procedure and the alga is capable of precipitating metals from the solution. This study demonstrates that changes in culture and oxidation-reduction conditions may result in a different bioaccumulation of metals. 相似文献
46.
47.
Peter Alliger Wolfgang Traut Eric Carstens Ellen Fanning 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1988,951(2-3)
A monkey cell factor that interacts specifically with double- and single-stranded DNA sequences in the early domain of the simian virus 40 (SV40) core origin of replication was identified using gel-retention assays. The protein was enriched over 1200-fold using ion-exchange and affinity chromatography on single-strand DNA cellulose. Binding of protein to mutant origin DNA restriction fragments was correlated with replication activity of the mutant DNAs. Exonuclease footprint experiments on single-stranded DNA revealed prominent pause sites in the early domain of the core origin. The results suggest that this cellular protein may be involved in SV40 DNA replication. 相似文献
48.
49.
Verner P. Bingman Wolfgang Wiltschko 《Ethology : formerly Zeitschrift fur Tierpsychologie》1988,77(1):1-9
To find out the relative importance of the geomagnetic and solar cues for the orientation at the time of sunset, dunnocks were tested outdoors during the spring migration periods of 1982 and 1983. Experimental magnetic fields were produced by Helmholtz coils. In the various magnetic conditions, the following results were obtained:
- 1 In the local geomagnetic field, the dunnocks oriented in a seasonally appropriate northerly direction.
- 2 In a magnetic field the north of which was shifted 120° clock-wise to ESE, the birds showed a corresponding shift in their orientation.
- 3 In a vertical magnetic field without meaningful directional information, birds previously tested in either the local geomagnetic field or the shifted magnetic field now displayed axially bimodal orientation, with the axes of the two groups differing.
50.
Summary Genomic clones encoding two Volvox -tubulin genes have been isolated and shown to represent the only two -tubulin genes in the genome. Restriction fragment length polymorphism analysis was used to demonstrate that the two genes are genetically linked. One of these genes was sequenced and the mRNA start site(s) determined by primer extension. A comparison of its sequence to those of the two -tubulin genes of Chlamydomonas revealed: (1) a high degree of conservation of the coding region, with the predicted amino acid sequence differing only in the C-terminal residue; (2) extensive sequence conservation in the 5 untranslated leader region and a 16 bp (putative regulatory) sequence in the promoter region; (3) the same number and location of introns, with a short region of homology in intron 1, but little significant homology in introns 2 and 3. 相似文献