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61.
Josef Holub 《Folia Geobotanica》1983,18(3):325-328
A list including 114 selected subspecies names from the bookSchübler andMartens, Flora von Würtemberg, 1834 is given. Twenty of them are very important for the present taxonomic classification. 相似文献
62.
Josef Holub 《Folia Geobotanica》1983,18(4):439-442
Four earlier proposed and invalidly published generic names ofLycopodiaceae are validated:Lateristachys (type:Lycopodium laterale R. Br.),Lycopodiastrum (type:Lycopodium casuarinoides Spring),Pseudodiphasium (type:Lycopodium volubile G. Forster) andPseudolycopodium (type:Pseudolycopodium densum (Rothm.) Holub). A new genusPseudolycopodiella (type:Lycopodium carolinianum L.) is described. New nomenclatural combinations are proposed for 17 species of these genera and ofLycopodiella. 相似文献
63.
Josef Flossdorf 《Journal of microbiological methods》1983,1(5):305-311
A rapid method to evaluate the (G+C)-content of bacterial DNA is described. About 2 × 108 cells are lysed by the combined action of detergents and enzymes and put into a CsCl-gradient without any purification. Up to five samples may be run at once. The high background absorption of cell-derived material other than DNA is overcome by novel collimating optics. 相似文献
64.
JiRí Moos Leopold Veselskýa Jana Pknicov Josef Drahord 《Molecular reproduction and development》1992,33(2):165-171
Sperm coating proteins of 16, 17, and 19 kDa have been purified from boar seminal plasma. The 17 kDa protein has been identified as an antigen recognized by monoclonal antibody ACR.3 and is thus identical to low molecular mass zona pellucida binding protein from boar spermatozoa (Moos et al., 1990). The 17 and 19 kDa proteins are glycosylated and tend to form hetero-complexes. The 17 kDa ACR.3 antigen is sequentially released from the sperm cell surface during capacitation and, after induction of the acrosome reaction, the 16 kDa form was also observed. Immunocytochemical studies on boar reproductive tissues have suggested that the seminal vesicle epithelium may be the source of these proteins. 相似文献
65.
Josef Holub 《Folia Geobotanica》1991,26(3):331-340
Eight newRubus species are described from the area of Czech Republic (western Czechoslovakia), four of them belonging to ser.Discolores, and one by one to subsect.Rubus, ser.Rhamnifolii, ser.Micantes and ser.Hystrices. *** DIRECT SUPPORT *** AAY02002 00005 相似文献
66.
Summary Two 4-hydroxybenzoate decarboxylase activities and a phenol carboxylase activity were found in cell-free extracts of a defined, 4-hydroxybenzoate- or phenol-grown consortium. Both decarboxylase activities were loosely membrane-associated and required K+ but a different pH and ion strength. Loss of activity of both decarboxylases by EDTA could be compensated by Zn2+ ions. The K
m values for 4-hydroxybenzoate and K+ of the decarboxylase activities with pH optima at 6.4 or 7.8 were 0.02 and 2.5 or 0.004 and 0.5 mm, respectively. 3,4-Dihydroxybenzoate, 3,4,5-tridydroxybenzoate, 3,5-dimethoxy-4-hydroxybenzoate and 3-chloro-4-hydroxybenzoate were also decarboxylated by both enzyme activities. The phenol carboxylase was a soluble enzyme with its pH optimum at 6.5. It required K+, Rb+ or NH
inf4
sup+
as monovalent, Zn2+, Mg2+, Mn2+ or Ni2+ as divalent cations and catalysed the carboxylation of phenol if 2,4-,2,3,4- or 2,4,6-hydroxybezoates were absent. The three enzyme activities were not influenced by Avidin and thus were probably not biotin-dependent enzymes.
Offprint requests to: J. Winter 相似文献
67.
Control of the Lysine Biosynthesis Sequence in Corynebacterium glutamicum as Analyzed by Overexpression of the Individual Corresponding Genes 总被引:7,自引:2,他引:5 下载免费PDF全文
The gene cluster that codes for feedback-resistant aspartate kinase (lysCα and lysCβ) and aspartate semialdehyde dehydrogenase (asd) was cloned from a mutant strain of Corynebacterium glutamicum. Its functional analysis by subcloning, enzyme assays, and type of aspartate kinase regulation enabled the isolation of a fragment for separate expression of the feedback-resistant kinase without aspartate semialdehyde dehydrogenase expression. This was used together with other clones constructed (J. Cremer, L. Eggeling, and H. Sahm, Mol. Gen. Genet. 220:478-480, 1990) to overexpress individually each of the six genes that convert aspartate to lysine. Analysis of lysine formation revealed that overexpression of the feedback-resistant kinase alone suffices to achieve lysine formation (38 mM). Also, sole overexpression of wild-type dihydrodipicolinate synthase resulted in lysine formation but in a lower amount (11 mM). The other four enzymes had no effect on lysine secretion. With a plasmid overexpressing both relevant enzymes together, a further increase in lysine yield was obtained. This shows that of the six enzymes that convert aspartate to lysine the kinase and the synthase are responsible for flow control in the wild-type background and can be useful for construction of lysine-producing strains. 相似文献
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Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448