Search results for "OxyR"
showing 10 items of 216 documents
Notizen: Unterschiedliche Desoxyribonuclease-Aktivitäten im Seminalplasma von Bullen/Different Deoxyribonuclease-Activities in Bull Seminal Plasma
1976
By means of the in situ assay of deoxyribonucleases in DNA-containing polyacrylamide gels after separation by micro-disc-electrophoresis different deoxyribonucleases are detectable in bull seminal plasma. There are two groups of acid deoxyribonuclease-activities with a pH optimum at pH 5.0, one with a pH optimum at pH 7.4 and an additional one with a pH optimum at pH 8.5.
Bleomycin, an Antibiotic That Removes Thymine from Double-Stranded DNA
1977
Publisher Summary This chapter reviews that bleomycins are members of a new class of DNA-modifying agents, the quasi-enzymes. In in vitro systems, bleomycin first removes thymines from native DNA by hydrolysis of the N-glycosidic bonds without modifying the deoxyribose moiety. In a second step, single-strand scissions occur at the sites of the nonglycosidic deoxyribose moieties, resulting in the formation of 3'-OH and 5'-P termini. It is suggested that bleomycin is bound to DNA by interaction of the positively charged terminal amine moiety with the negatively charged phosphate group in DNA; intercalation seems to be involved in binding. Bleomycin is inactivated by copper and zinc ions, prob…
WRN protects against topo I but not topo II inhibitors by preventing DNA break formation
2008
The Werner syndrome helicase/3′-exonuclease (WRN) is a major component of the DNA repair and replication machinery. To analyze whether WRN is involved in the repair of topoisomerase-induced DNA damage we utilized U2-OS cells, in which WRN is stably down-regulated (wrn-kd), and the corresponding wild-type cells (wrn-wt). We show that cells not expressing WRN are hypersensitive to the toxic effect of the topoisomerase I inhibitor topotecan, but not to the topoisomerase II inhibitor etoposide. This was shown by mass survival assays, colony formation and induction of apoptosis. Upon topotecan treatment WRN deficient cells showed enhanced DNA replication inhibition and S-phase arrest, whereas af…
The interaction of transition metal complexes with deoxyribonucleic acid
2011
La presente tesi `e suddivisa in quattro capitoli. Il Capitolo 1 `e di carattere introduttivo. Nel Capitolo 2 viene trattata la sintesi e la caratterizzazione strutturale dei complessi di CuII, NiII e ZnII con il legante N,N’-Bis-5-(trietil ammonio metil salicilidene)-1,2- fenilendiammina. Inoltre, vengono riportati e confrontati i risultati dello studio della loro interazione con DNA nativo. Viene in particolare mostrato come l’interazione con DNA aumenti la stabilit`a fotochimica del complesso di ZnII. Infine, vengono evidenziati gli effetti del confinamento in cristalli liquidi sull’interazione del complesso di CuII e DNA.Nel Capitolo 3 `e riportata la sintesi e la caratterizzazione stru…
Tissue-Specific Dynamics in the Endophytic Bacterial Communities in Arctic Pioneer Plant
2020
The rapid developments in the next-generation sequencing methods in the recent years have provided a wealth of information on the community structures and functions of endophytic bacteria. However, the assembly processes of these communities in different plant tissues are still currently poorly understood, especially in wild plants in natural settings. The aim of this study was to compare the composition of endophytic bacterial communities in leaves and roots of arcto-alpine pioneer plant Oxyria digyna, and investigate, how plant tissue (leaf or root) or plant origin affect the community assembly. To address this, we planted micropropagated O. digyna plants with low bacterial load (bait pla…
Assembly and functioning of endophytic bacterial communities in arcto-alpine pioneer plant Oxyria digyna
2019
Plant microbiomes consist of diverse communities of microorganisms, among which bacteria are highly abundant. The microbiomes are crucial for plants as they rely on their microbial associates for many essential functions. The goal of this thesis was to study the functional diversity and assembly rules of endophytic bacterial communities in different plant tissues of the arcto-alpine pioneer plant species, Oxyria digyna. I used high-throughput sequencing and bacterial isolations to characterize the endophytic communities in the leaves and roots of native O. digyna plants (wild plants) and micropropagated aseptic plants (bait plants) in the field. Wild plants and tissue-propagated bait plants…
Self-assembly of 2,8,14,20-tetraisobutyl-5,11,17,23-tetrahydroxyresorc[4]arene
1999
We report herein the observation of a hexameric structure of a hydroxyresorc[4]arene in the solid state, enclosing a large interior space. This artificial molecular container is stabilized only by hydrogen bonds. The tendency to form aggregates in solution is demonstrated mainly by means of ESI-MS methods.
Phosphorylation of the Goodpasture antigen by type A protein kinases.
1995
Collagen IV is the major component of basement membranes. The human alpha 3 chain of collagen IV contains an antigenic domain called the Goodpasture antigen that is the target for the circulating immunopathogenic antibodies present in patients with Goodpasture syndrome. Characteristically, the gene region encoding the Goodpasture antigen generates multiple alternative products that retain the antigen amino-terminal region with a five-residue motif (KRGDS). The serine therein appears to be the major in vitro cAMP-dependent protein kinase phosphorylation site in the isolated antigen and can be phosphorylated in vitro by two protein kinases of approximately 50 and 41 kDa associated with human …
Review of George W. Houston, Inside Roman Libraries: Book Collections and Their Management in Antiquity
2017
By examining in detail the results of George W. Houston's recent research on Roman libraries, the present contribution discusses the structure, content, and socio-cultural function of book collections in the Roman world. Special attention is devoted to the (often overlooked) relationship between intellectual trends and material culture as well as to the highly representative sites of Herculaneum and Oxyrhynchus.
Relation of PvuII site polymorphism in the COL1A2 gene to the risk of fractures in prepubertal Finnish girls.
2003
Genetic susceptibility to fractures may be detectable in early childhood. We evaluated the associations between the polymorphic PvuII site of the COL1A2 gene and bone properties assessed by different modalities (dual-energy X-ray absorptiometry; peripheral quantitative computed tomography; gel coupling scanning quantitative ultrasonometry; ultrasound bone sonometry), bone turnover markers, and the occurrence of fractures in 244 prepubertal Finnish girls. Tanner stage and physical characteristics did not differ significantly among girls with different COL1A2 genotypes. The polymorphism was not significantly associated with different bone properties or any of the bone turnover markers when gi…