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951.
Cell suspension cultures of the hornwort Anthoceros agrestis Paton (Anthocerotaceae) were cultivated and characterized in CB-media containing 2 and 4% sucrose. The suspension cells accumulated rosmarinic acid up to 5.1% of the cell dry weight as well as caffeoyl-4'-hydroxyphenyllactate. Moreover, a more hydrophilic compound was detected which was isolated and identified as rosmarinic acid 3'-O-beta-D-glucoside, a new rosmarinic acid derivative. This new rosmarinic acid derivative was found up to 1.0% of the cell dry weight in suspension cells of A. agrestis. 相似文献
952.
953.
Nuclear and mitochondrial DNA repair: similar pathways? 总被引:7,自引:0,他引:7
Mitochondrial DNA (mtDNA) alterations are implicated in a broad range of human diseases and alterations of the mitochondrial genome are assumed to be a result of its high susceptibility to oxidative damage and its limited DNA repair compared to nuclear DNA (nDNA). Characterization of DNA repair mechanisms has generally focused on these processes in nDNA but increasing interest and research effort have contributed to our knowledge of the mechanisms underlying DNA repair in mitochondria. In this review, we make comparisons between nDNA and mtDNA repair pathways and propose a model for how these pathways interact in mitochondria. 相似文献
954.
Olivier Habimana Trond Møretrø Solveig Langsrud Lene K Vestby Live L Nesse Even Heir 《BMC veterinary research》2010,6(1):48
Background
The presence of Salmonella enterica serovars in feed ingredients, products and processing facilities is a well recognized problem worldwide. In Norwegian feed factories, strict control measures are implemented to avoid establishment and spreading of Salmonella throughout the processing chain. There is limited knowledge on the presence and survival of the resident microflora in feed production plants. Information on interactions between Salmonella and other bacteria in feed production plants and how they affect survival and biofilm formation of Salmonella is also limited. The aim of this study was to identify resident microbiota found in feed production environments, and to compare the survival of resident flora strains and Salmonella to stress factors typically found in feed processing environments. Moreover, the role of dominant resident flora strains in the biofilm development of Salmonella was determined. 相似文献955.
Maike Petersen 《Planta》1993,191(1):18-22
Rosmarinic acid synthase from cell cultures of Coleus blumei Benth. was purified to apparent homogeneity by fractionated ammonium sulfate precipitation (60–80% saturation), hydrophobic interaction chromatography, affinity chromatography and gel filtration. This purification procedure resulted in a 225-fold-enriched specific enzyme activity with a yield of 9%. The protein preparation was apparently pure according to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimensional gel electrophoresis. The apparent molecular mass determined by gel filtration and SDS-PAGE was 77 kDa, indicating that rosmarinic acid synthase is a monomeric enzyme.Abbreviations DTT
dithiothreitol
- HIC
hydrophobic interaction chromatography
- RA
rosmarinic acid
- RAS
rosmarinic acid synthase
- SDS-PAGE
sodium dodecyl sulfate-polyacrylamide gel electrophoresis
The financial support of the Deutsche Forschungsgemeinschaft is gratefully acknowledged. Two-dimensional gel electrophoresis was done with the help of Dr. Guy Bauw, University of Gent, Belgium. 相似文献
956.
The stipitate pore-bearing fungus Polyporus tricholoma (Polyporus infrageneric group Polyporellus) is commonly reported from Mesoamerica and more rarely from the palaeotropics. Collections from Puerto Rico, Mexico, and
Costa Rica did not differ morphologically, but their monokaryotic cultures revealed the existence of three interINcompatibility
groups. These putative cryptic species exist sympatrically in Costa Rica. Sequencing, restriction enzyme digestion, and specific
primers targeting the ITS region of nuclear ribosomal DNA (ITS 1-5.8S-ITS2) could only partly be used for detecting intercompatibility
groups. Heterogeneity within the rDNA repeat was observed. Molecular evidence supports the existence of a close relative in
Australia. 相似文献
957.
958.
959.
Development and validation of a highly efficient protocol of porcine somatic cloning using preovulatory embryo transfer in peripubertal gilts 总被引:2,自引:0,他引:2
Petersen B Lucas-Hahn A Oropeza M Hornen N Lemme E Hassel P Queisser AL Niemann H 《Cloning and stem cells》2008,10(3):355-362
The efficiency of porcine somatic nuclear transfer (born piglets/transferred embryos) is low. Here, we report a highly efficient protocol using peripubertal gilts as recipients synchronized to ovulate approximately 24 h after transfer of cloned embryos. Retrospectively, we compared the efficiency of two different synchronization protocols: In group 1, recipient animals were synchronized to ovulate approximately 6 h prior to surgical embryo transfer while in group 2 the animals were treated to ovulate 24 h after embryo transfer. In total, 1562 cloned embryos were transferred to 12 recipients in group 1; two of them became pregnant (16.7%). One pregnancy was lost on day 32, the second pregnancy went to term, and led to the birth of one healthy piglet after Cesarean section. In group 2, 1531 cloned embryos were transferred to 12 recipients. Nine recipients (75.0%) became pregnant as determined by ultrasound scanning on day 25. All pregnancies went to term and delivered a total of 47 live-born piglets. The cloning efficiency of both groups differed significantly (group 1: 0.1%, group 2: 3.1%, p < 0.05). This modified protocol was then applied in subsequent experiments using different types of transgenic and nontransgenic donor cells with similar success rates. Results show that this protocol is robust and highly reproducible, and can thus be employed for routine production of cloned pigs. 相似文献
960.