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11.
Molecular organisation of the quinic acid utilization (QUT) gene cluster in Aspergillus nidulans 总被引:9,自引:0,他引:9
Alastair R. Hawkins Heather K. Lamb Melanie Smith John W. Keyte Clive F. Roberts 《Molecular & general genetics : MGG》1988,214(2):224-231
Summary The functional integrity of the QUTB gene (encoding quinate dehydrogenase) has been confirmed by transformation of a qutB mutant strain. The DNA sequence of the contiguous genes QUTD (quinate permease), QUTB and QUTG (function unknown) has been determined and analysed, together with that of QUTE (catabolic 3-dehydroquinase). The QUTB sequence shows significant homology with the shikimate dehydrogenase function of the complex AROM locus of Aspergillus nidulans, and with the QA-3 quinate dehydrogenase and QA-1S (repressor) genes of Neurospora crassa. The QUTD gene shows strong homology with the N. crassa QA-Y gene and QUTG with the QA-X gene. QUTD, QUTB, and QUTG, QUTE form two pairs of divergently transcribed genes, and conserved sequence motifs identified in the two common 5 non-coding regions show significant homology with UAS
GAL
and UAS
QA
sequences of the Saccharomyces cerevisiae and N. crassa Gal and QA systems. In addition, conserved 5 sequences homologous to the mammalian CAAT box are noted and a previously unreported conserved 22 nucleotide motif is presented. 相似文献
12.
Lakhu M. Keshvara Elizabeth M. Newton A. Heather Good Ole Hindsgaul Monica M. Palcic 《Glycoconjugate journal》1992,9(1):16-20
ELISA assays have been developed for (1–3)N-acetylgalactosaminyltransferase (blood group A transferase) and (1–3)galactosyltransferase (blood group B transferase) activities. In these assays, microtitre plates coated with the bovine serum albumin conjugate of a synthetic Fuc1–2Gal-R acceptor substrate are incubated with the appropriate nucleotide donor (UDP-GalNAc or UDP-Gal) and human serum as the enzyme source. The resulting trisaccharide products Fuc1–2(GalNAc1–3)Gal-R-BSA or Fuc1–2(Gal1–3)Gal-R-BSA are detected and quantified with monoclonal antibodies selected not to cross-react with the substrate structure. With less than a microliter of human serum, product formation is proportional to enzyme concentration and to time of incubation of up to 90 min. 相似文献
13.
Mapping of the structural gene for S-adenosyl homocysteine hydrolase to mouse Chromosome 2, and related sequences to Chromosomes 8 and X 总被引:1,自引:0,他引:1
Alison Pilz Paul Le Tissier Heather Moseley Jo Peters Cathy Abbott 《Mammalian genome》1992,3(11):633-636
Comparative mapping studies in human and mouse have shown that, to date, human Chromosome (Chr) 20 is completely syntenic with distal mouse Chr 2. The structural locus for S-adenosyl-l-homocysteine hydrolase (EC 3.3.1.1) in human, AHCY, maps to 20 qterq13.1, and we report here that the homologous locus in the mouse, Ahcy, maps to distal mouse Chr 2 with gene order Pcna-Ahcy-Ada. Analysis of 123 progeny of an interspecific backcross between a laboratory stock, AN, and Mus spretus using a rat cDNA probe revealed the presence of at least two other Ahcy-related sequences segregating independently in the mouse genome. One, Ahcy-rs1, was mapped to Chr 8 in the BXH recombinant inbred strains, and the other, Ahcy-rs2, shows a pattern of inheritance consistent with X-linkage. 相似文献
14.
Summary The removal of fungal spores, urediniospores ofMelampsora medusae and conidia ofPestalozzia sp., from the leaf surfaces ofPopulus xeuramericana (Dode) Guinier cv. I-488 was assessed using three cultural techniques conventionally employed in phylloplane studies. The method of removal and the original density of spore deposition, but not the interaction of these factors, were significant determinants of variability in spore removal. Irrespective of the original density of deposition, the leaf print method was the most, and the leaf washing technique the least, efficient means of spore removal from the leaf surface. Factors which could contribute to this difference in efficiency are discussed. 相似文献
15.
Henry Schneider George Mahmourides John L. Labelle Hung Lee Nancy Maki Heather J. McNeill 《Biotechnology letters》1985,7(5):361-364
The formation of ethanol, xylitol, ribitol, arabitol and acetic acid from D-xylose byPachysolen
tannophilus correlated with the limitation of growth. The correlation was consistent with these products being secondary metabolites.Issued as NRCC Publication Number 24259. 相似文献
16.
Stability of tissue culture medium pH as a function of autoclaving,time, and cultured plant material
Robert M. Skirvin Mel C. Chu Mary L. Mann Heather Young Joseph Sullivan Thomas Fermanian 《Plant cell reports》1986,5(4):292-294
Autoclaving is a standard procedure for sterilizing nutrient media for plant tissue cultures. Most tissue cultures are grown at pH 5.2 to 5.8 with pH adjustments being made prior to autoclaving. This paper reports that there are significant differences between initial pH levels and pH levels following autoclaving, particularly in the pH range of 5.7 to 8.5. This effect is noted with and without agar. In addition, we report that with time the pH of the medium drifts into the acid range. When Cucumis callus was added to the medium, the pH was changed significantly within 48 hours. The amount and direction (increase or decrease of pH) was significantly correlated with the original pH. This suggests that researchers should be wary of the true pH situation in their medium. In addition, in publications authors should specify whether their medium pH value was determined before or after autoclaving. 相似文献
17.
Biophysical and Biochemical Studies on Rhinovirus and Poliovirus II. Chemical and Hydrodynamic Analysis of the Rhinovirion 总被引:2,自引:2,他引:0
Chemical analysis of rhinovirus 14 revealed a ribonucleic acid (RNA) content of 29.8% and a high adenylic acid content (35%). A partial specific volume of 0.682 cm3/g was obtained for the rhinovirion. Rhinovirus and poliovirus had identical sedimentation coefficients of 158S. A diffusion coefficient of 1.71 × 10−7 cm2/sec was consistent with a hydrated diameter of 25 nm for the rhinovirion. The calculated molecular weights of the rhinovirion and its genome were 7.1 × 106 and 2.1 × 106 daltons, respectively. Sedimentation analysis of infectious RNA confirmed the similarity of the molecular size of the poliovirus and rhinovirus genomes. 相似文献
18.
Heather Aslin 《Ethology : formerly Zeitschrift fur Tierpsychologie》1974,35(2):187-208
Das Verhalten des Beuteltiers Dasyuroides byrnei in Gefangenschaft wurde untersucht. Dasyuroides ist nachtaktiv und verbirgt sich tagsüber in einem Bau oder Schlupfwinkel. Körperhaltung, Fortbewegungsarten, Höhlengraben, Beutefang und andere Verhaltensweisen sind beschrieben. Das Duftmarkieren hat Mitteilungswert. Beide Geschlechter setzen Duftstoff ab, indem sie ihre Sternaldrüsen und Kloakengegend an Gegenständen reiben. Freundschaftliche, kämpferische, sexuelle und mütterliche Verhaltensweisen werden beschrieben. Dasyuroides scheint kein geselliges Tier zu sein; Angriffe gegen Artgenossen führen selten zu Verletzungen, weil das Angriffsverhalten stark stilisiert ist. Wachstum und Entwicklung der Jungen wurden verfolgt. Die durchschnittliche Wurfgröße beträgt fünf oder sechs; die Jungen bleiben an den Zitzen des ♀ bis zum 56. Lebenstag. Mit 100 Tagen können sie entwöhnt werden. Das Verhalten dieser Art wird mit anderen Arten der Familie Dasyuridae verglichen, auch mit Plazentaliern. 相似文献
19.
Staining patterns suggest that in the adeno-associated satellite virion there exist quasi single-stranded regions which are renatured after extraction to exhibit double strandedness. 相似文献
20.