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11.
Summary Tarantula heart cDNA libraries were screened with synthetic oligonucleotide probes deduced from the highly conserved amino acid sequences of the two copper-binding sites, copper A and copper B, found in chelicerate hemocyanins. Positive cDNA clones could be obtained and four different cDNA types were characterized. 相似文献
12.
Sensitized guinea pigs produced specific IgG and IgE antibodies toward Cladosporium and Alternaria. In presence of fungal extracts, nasal mast cells degranulate. Ultrastructural modifications of the cells during degranulation have been established. The ciliary epithelium and the ciliary beating are not affected by fungal allergens. 相似文献
13.
P. Schmitt C. Couvreur J. F. Cavin H. Prévost Ch. Diviès 《Applied microbiology and biotechnology》1988,29(5):430-436
Summary The effects of pH, temperature and concentration of citrate were investigated to achieve an optimal production of diacetyl, acetoin and C2 compounds such as acetaldehyde, acetate and ethanol for free and immobilized cells. The critical conditions of culture, 22°C, pH 4.8, increased the production of C4 compounds (diacetyl, acetoin, 2, 3 butylene glycol), C2 compounds (acetaldehyde, ethanol, acetate) and formate. A higher yield of C2 and C4 compounds was observed for the immobilized cells than for the free cells in continuous culture. At 75 mMol/l of citrate, the citrate bioconversion yield was 42.8% and 80% for free and immobilized cells, respectively. This paper discusses citrate and lactose utilization and NADH2 part on diacetyl reduction. 相似文献
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Cell-suspension cultures were initiated from embryogenic calli of various barley cultivars. Seven fast-growing suspension lines were obtained from four different cultivars (cvs. Dissa, Emir, Golden Promise and Igri). Two of these cell suspensions showed morphogenic capacity. From a cell suspension of cv. Dissa, albino plantlets were regenerated when aggregates were cultured on solid medium. Aggregates of cv. Igri usually stopped differentiation at the globular stage, but occasionally formed scutellum-like structures. Five suspension lines were used for protoplast isolation and culture. Dividing protoplasts were obtained from all lines, but with cv. Igri a few divisions only and no further development were observed. Protoplasts from the various lines differed in the time of first division (2–14 d), division frequency (0.09–70.9%) and efficiency of colony formation (0.09–7.3%). Protoplasts isolated from the morphogenic cell suspension of cv. Dissa developed compact calli which sporadically regenerated albino plantlets.Abbreviations CC, MS, N6, SH, Kao8p
culture media; see Material and methods
- cv
chltivar
- dicamba
3,6-dichloro-o-anisic acid
- 2,4-D
2,4-dichlorophenoxyacetic acid
- picloram
4-amino-3,5,6-trichloropicolinic acid 相似文献
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Anna Pugatshova ülle Kikas Margit Prüssel Aivo Reinart Eduard Tamm et al. 《Plant Growth Regulation》1991,10(2):177-178
Book Review
Principles of environmental physicsJ.L. Monteith and M.H. Unsworth Second edition. London: Edward Arnold, 1990. xii + 291 pages. £30.00 (hardback), £14.95 (paperback). ISBN 0-7131-2931-X 相似文献20.
Reinhard Piechocki Dagmar Kupper Ariel Quiñones Renate Langhammer 《Molecular & general genetics : MGG》1986,202(1):162-168
Summary The dnaQ (mutD) gene product which encodes the -subunit of the DNA polymerase III holoenzyme has a central role in controlling the fidelity of DNA replication because both mutD5 and dnaQ49 mutations severely decrease the 3–5 exonucleolytic editing capacity.It is shown in this paper that more than 95% of all anaQ49-induced base pair substitutions are transversions of the types G:C-T:A and A:T-T:A. Not only is this unusual mutational specificity precisely that observed recently for a number of potent carcinogens such as benzo(a) pyrene diolepoxide (BPDE) and aflatoxin B1 (AFB1), which are dependent on the SOS system to mutagenize bacteria, but it is also seen for the constitutively expressed SOS mutator activity in E. coli tif-1 strains as well as for the SOS mutator activity mediated gap filling of apurinic sites. Because the G:C-T:A and A:T-T:A transversions can either result from the insertion of an adenine across from apurinic sites or arise due to the incorporation of syn-adenine opposite a purine base, we postulate that the DNA polymerase III holoenzyme also has a reduced discrimination ability in a dnaQ49 background.The introduction of a lexA (Ind-) allele, which prevents the expression of SOS functions, led to a significant reduction in the dnaQ49-caused mutator effect.Both, the mutational specificity observed and the partial lexA
+ dependence of the mutator effect provoke a reanalysis of the hypothesis that the DNA polymerase III holoenzyme can be converted into the postulated but until now unidentified SOS polymerase. 相似文献