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21.
Dr. Wolfgang Schwabe Andreas Weihe Thomas Börner Manfred Henning Johannes-Günther Kohl 《Current microbiology》1988,17(3):133-137
The plasmid content and toxicity of nine different strains ofMicrocystis aeruginosa have been analyzed. The two toxic strains of the HUB Culture Collection were found to carry each two plasmids, pMA1 and pMA2, of 2.9 kb and 8.5 kb, respectively. In strains PCC 7813 and PCC 7820, also toxic, two different plasmids of 2.6 kb and 16 kb were detected. Hybridization experiments showed that there exists no sequence homology between the pMA plasmids and the plasmids found in the PCC strains; but the pMA plasmids hybridized to chromosomal DNA of the toxic strains PCC 7820, PCC 7813, HUB 063, and the nontoxic strain HUB 5-3. In nontoxic strains no or at most one plasmid of unstable occurrence could be detected. Only one of the toxic strains investigated, SAG 14.85 (NRC-1), contained no plasmid. 相似文献
22.
Simultaneous saccharification and protein enrichment fermentation of sugar beet pulp 总被引:1,自引:0,他引:1
Summary A product with 40 % protein content was obtained from sugar beet pulp (1.25–2.0 mm) in 48 h one stage (simultaneous) saccharification/fermentation process under optimized conditions using a specific enzyme mixture andCandida
tropicalis strain, also saving about 40 % enzymes in comparison to a 2-stage process. 相似文献
23.
Summary For the protein upgrading of sugar-beet pulp in solid state fermentation byTrichoderma
reesei andFusarium
oxysporum, serveral conditions were studied to prepare an economical preculture for large scale process. The best performance was shown by a preculture obtained in 24 h from 1.5 % molasses solution at pH 4.5–5.0 with 1.0 % milled beet pulp. 相似文献
24.
Klaus D. Jürgens Manfred Pietschmann Kazuhiro Yamaguchi Traute Kleinschmidt 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1988,158(4):469-477
Summary The oxygen binding properties of the blood of the camelid species vicuna, llama, alpaca and dromedary camel were measured and evaluated with respect to interspecific differences. The highest blood oxygen affinity, not only among camelids but of all mammals investigated so far, was found in the vicuna (P50=17.6 Torr compared to 20.3–21.6 Torr in the other species). Low hematocrits (23–34%) and small red blood cells (21–30 m3) are common features of all camelids, but the lowest values are found in theLama species. Capillary densities were determined in heart and soleus muscle of vicuna and llama. Again, the vicuna shows exceptional values (3720 cap/mm2 on average in the heart) for a mammal of this body size. Finally, heart weight as percent of body weight is higher in the vicuna (0.7–0.9%) than in the other camelids studied (0.5–0.7%). The possibility that these parameters, measured in New World tylopodes at sea level, are not likely to change considerably with transfer to high altitude, is discussed.In the vicuna, a unique combination of the following features seems to be responsible for an out-standing physical capability at high altitude: saturation of blood with oxygen in the lung is favored by a high blood oxygen affinity, oxygen supply being facilitated by low diffusion distances in the muscle tissue. Loading, as well as unloading, of oxygen is improved by a relatively high oxygen transfer conductance of the red blood cells, which is due to their small size and which compensates the negative effect of a low hematocrit on the oxygen conductance of blood. Blood oxygen transport is presumably favored by two factors: a relatively large heart mass and, as a result of low hematocrit, a low blood viscosity. Both are advantageous for achieving a high maximal cardiac output. 相似文献
25.
Tau protein has been shown to be an integral component of Alzheimer paired helical filaments (PHF). However, the extent to which tau is incorporated into PHF has not been clear because the antibodies used to label PHF generally do not have precisely defined epitopes. Here we define the antigenic sites for five monoclonal antibodies that react with tau and cross-react with SDS-extracted neurofibrillary tangles. The reactive sites were determined by screening a lambda gt11 sublibrary expressing small fragments of the tau sequence. The mapped epitopes were found to span almost the entire length of tau, suggesting that PHF contains tau in its entirety or nearly in its entirety. One antibody was found to cross-react with microtubule-associated protein 2, implying some degree of homology between the two proteins. 相似文献
26.
27.
Juliane Plieth Frauke Rininsland Manfred Schlösser David N. Cooper Jochen Reiss 《Human genetics》1992,88(3):283-287
Summary In Central Europe, the F508 deletion accounts for approximately 75% of mutations in the cystic fibrosis transmembrane conductance regulator gene causing cystic fibrosis. The remainder comprise a large number of individually infrequent mutations whose detection requires a disproportionately large effort. However, a sizeable proportion of non-F508 mutations have been found to cluster within exon 11. We have taken advantage of this clustering to detect a total of five previously described point mutations present on 26/72 (36%) non-F508 chromosomes by polymerase chain reaction/direct sequencing of exon 11. These exon 11 mutations were then subjected to single-strand conformation polymorphism (SSCP) analysis, which was shown (i) to discriminate reliably between mutant and wildtype alleles and (ii) to generate reproducible mutation-specific band patterns. This analysis thus represents the first attempt to assess SSCP analysis retrospectively, and serves to illustrate the potential of this screening technique in diagnostic medicine. 相似文献
28.
29.
Inhibition of early steps of de novo fatty-acid biosynthesis by different xenobiotica 总被引:1,自引:0,他引:1
The importance of the early steps of de novo fatty-acid biosynthesis is discussed in terms of rate-limiting enzymic reactions with respect to their inhibition by xenobiotics. The inhibitory spectra of allicin as an inhibitor of the acetyl-CoA-synthase, two classes of graminicides (cyclohexane-1,3-diones and aryloxyphenoxypropionic acids) as inhibitors of acetyl-CoA-carboxylase, and the two antibiotics cerulenin and thiolactomycin, which affect the condensing step in fatty-acid biosynthesis, are compared. 相似文献
30.
The infection of cucumber leaves by Colletotrichum lagenarium was studied using cytological methods. Its progress in untreated plants was compared with that in plants in which systemic resistance had been induced by pre-infecting the first true leaf with the same fungus. In induced plants, a reduction of fungal development was observed at the leaf surface, in the epidermis, and in the mesophyll. On the leaf surface, formation of appressoria was slightly reduced. In the epidermis, enhanced formation of papillae beneath appressoria, and possibly increased lignification of entire cells, correlated with reduced development of infection hyphae. Papillae contained callose, identified by staining with aniline-blue fluorochrome and digestion with -1,3-glucanase, as a main structural component. In the mesophyll, reduced fungal development provided evidence for the existence of an additional induced defence reaction. The results imply that preinfection elicited a systemic, multicomponent defence reaction of the host plant against the fungus.Dedicated to the memory of Professor H. Grisebach 相似文献