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Summary Small plasmids ofClostridium acetobutylicum and related strains were isolated and studied. Their restriction maps were established and different hybrid plasmids were constructed by ligation with plasmid pHV33. 相似文献
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Variants of the anti-Müllerian hormone gene in a compound heterozygote with the persistent Müllerian duct syndrome and his family 总被引:25,自引:0,他引:25
Danièle Carré-Eusèbe Sandrine Imbeaud Madeleine Harbison Maria I. New Nathalie Josso Jean-Yves Picard 《Human genetics》1992,89(4):389-394
Summary The human genome contains a large number of interspersed simple repeat sequences that are variable in length and can therefore serve as highly informative, polymorphic markers. Typing procedures include conventional multilocus and single locus probing, and polymerase chain reaction aided analysis. We have identified simple sequences in a cosmid clone stemming from the human Y chromosome and consisting of (gata)n repeats. We have compared these with two equivalent simple repeat loci from chromosome 12. After amplifying the tandemly repeated motifs, we detected between four and eight different alleles at each of the three loci. Codominant inheritance of the alleles was established in family studies and the informativity of the simple repeat loci was determined by typing unrelated individuals. The polymorphisms are suitable for application in linkage studies, practical forensic case work, deficiency cases in paternity determination, and for studying ethnological questions. The mutational mechanisms that bring about changes in simple repeats located both on the autosomes and on the sex chromosomes, are discussed.Professor Dr. Otto Prokop (Humboldt-Universität Berlin) on the occasion of his 70th birthday 相似文献
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Juana J. Perdomo Pierre Gounon Madeleine Schaeverbeke Jean Schaeverbeke Vanina Groult Marie P. Jacob Ladislas Robert 《Journal of cellular physiology》1994,158(3):451-458
Mesenchymal cells (fibroblasts, smooth muscle cells) and endothelial cells were shown to interact with elastin fibers. The strong adhesion of elastin fibers to these cells is mediated by a cell membrane complex with a major glycoprotein component of 120 kDa designated as elastonectin. This interaction was studied by transmission electron microscopy (TEM) and immunocytochemical techniques using antibodies raised against the elastin adhesive proteins. When fibroblasts and smooth muscle cells were cultured in presence of elastin fibers, TEM showed an adhesion mechanism that takes place over several sites along the plasma membrane of these cells. Endothelial cells showed a very close association with elastin, emitting “pseudopodia” that embody the fibers. TEM, indirect immunofluorescence, immunoperoxidase, and confocal microscopy showed the presence and localization of cell membrane components synthesized in large quantities when cells were incubated in presence of elastin. Cells without elastin fibers barely revealed the adhesive membrane complex. These results confirm and extend previous findings concerning the presence of an inducible cell membrane complex that mediates the adhesion of elastin fibers to these cell types. © 1994 Wiley-Liss, Inc. 相似文献
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Werner Landolt Madeleine Günthardt-Goerg Ilse Pfenninger Christoph Scheidegger 《Trees - Structure and Function》1994,8(4):183-190
Summary Cuttings of hybrid poplar (Populus × euramericana var. Dorskamp) were exposed to ozone (80 g/m3 from 2100 hours to 0700 hours, 180 g/m3 from 0700 hours to 2100 hours) for 3 months. Ozone reduced the starch content in leaves and stem bark, whereas starch granules accumulated in bundle sheath cells along small leaf veins. At the same time, sucrose and inositol content increased in the leaves. Mesophyll cells in the vicinity of the stomata were injured first, and droplet-like material appeared on their walls. In the sieve plates of fumigated trees, the pores showed a higher degree of narrowing than those of the control treatment. Cell collapse in the leaves was accompanied by water loss and an increase in air space. In the stems, the ozone treatment led to a reduced radial width, particularly in the xylem tissue. These results are discussed in relation to reduced or inhibited phloem loading and ozone-induced drought stress. The plants injured by ozone showed quite distinct patterns of metabolite responses as well as enzyme activities (PEP- and RubP-carboxylase) in the leaves from the top to the bottom. There were also remarkable differences in the reaction of sucrose and inositol between leaves and stem bark. Future research should therefore increasingly follow a whole-plant approach for a better understanding of complex plant reactions. 相似文献
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Two genes present on a transposon-like structure in Lactococcus lactis are involved in a Clp-family proteolytic activity 总被引:3,自引:0,他引:3
Dao Chao Huang Xian Fang Huang Georges Novel Madeleine Novel 《Molecular microbiology》1993,7(6):957-965
The lactose-protease plasmid pUCL22 of Lactococcus lactis subsp. lactis strain CNRZ270 contained two inverted copies of IS 1076 flanking a region of 3.7 kb. This internal region was sequenced and found to contain two large open reading frames, ORF1 and ORFP in opposite orientations. ORF1 consists of 2289 bp; the deduced 763-amino-acid sequence is similar to the ATPases of the ClpA family. It contains two well-conserved consensus ATP-binding sites. It was named ClpL. ORFP consists of 930 bp encoding a protein of 310 amino acids. No similarity with any known protein was found in GenBank data for ORFP. Increased ATP-dependent proteolytic activity was detected in extracts from Escherichia coli cells expressing the clpL and ORFP genes. 相似文献
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Molecular analysis of the Lactococcus lactis subspecies lactis CNRZ270 bidirectional theta replicating lactose plasmid pUCL22 总被引:1,自引:0,他引:1
pUCL22 is the lactose protease plasmid of Lactococcus lactis ssp. lactis CNRZ270. The nucleotide sequence of its replication region Rep22 contains a non-transcribed region, the replication origin, followed by a gene encoding a putative 388-amino-acid protein named Rep22A. The promoter regions of the rep22A and pC194 cat genes share strong similarities and the pUCL22 replicon exerted trans or cis negative control on the pC194 cat gene expression in L. lactis. We suggest that Rep22A binds to its own promoter as well as to the pC194 cat promoter and thus is autoregulated. We show that pUCL22 replicates mainly by a bidirectional theta mechanism in L. lactis, and is representative of a widely distributed replicon family, members of which could be co-resident. We propose that compatibility between these closely related replicons results from minor replication protein modifications coupled with base changes in their respective binding sites, supporting the co-existence of numerous related replicons in lactococcal strains. 相似文献