University of Hohenheim

About: University of Hohenheim is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Population & Soil water. The organization has 8585 authors who have published 16406 publications receiving 567377 citations.

Dry matter production and distribution of zinc in bread and durum wheat genotypes differing in zinc efficiency

Abstract: Six bread wheat (Triticum aestivum cvs. Kirac-66, Gerek-79, Aroona, ES 91-12, ES-14 and Kirkpinar) and four durum wheat (Triticum durum cvs. BDMM-19, Kunduru-1149, Kiziltan-91 and Durati) genotypes were grown under controlled environmental conditions in nutrient solution for 20 days to study the effect of varied supply of Zn (0 to 1 µM) on Zn deficiency symptoms in shoots, root and shoot dry matter production, and distribution of Zn in roots and shoots.

Diets rich in fructose, fat or fructose and fat alter intestinal barrier function and lead to the development of nonalcoholic fatty liver disease over time

Abstract: General overnutrition but also a diet rich in certain macronutrients, age, insulin resistance and an impaired intestinal barrier function may be critical factors in the development of nonalcoholic fatty liver disease (NAFLD). Here the effect of chronic intake of diets rich in different macronutrients, i.e. fructose and/or fat on liver status in mice, was studied over time. C57BL/6J mice were fed plain water, 30% fructose solution, a high-fat diet or a combination of both for 8 and 16 weeks. Indices of liver damage, toll-like receptor 4 (TLR-4) signaling cascade, macrophage polarization and insulin resistance in the liver and intestinal barrier function were analyzed. Chronic exposure to a diet rich in fructose and/or fat was associated with the development of hepatic steatosis that progressed with time to steatohepatitis in mice fed a combination of macronutrients. The development of NAFLD was also associated with a marked reduction of the mRNA expression of insulin receptor, whereas hepatic expressions of TLR-4, myeloid differentiation primary response gene 88 and markers of M1 polarization of macrophages were induced in comparison to controls. Bacterial endotoxin levels in portal plasma were found to be increased while levels of the tight junction protein occludin and zonula occludens 1 were found to be significantly lower in the duodenum of all treated groups after 8 and 16 weeks. Our data suggest that chronic intake of fructose and/or fat may lead to the development of NAFLD over time and that this is associated with an increased translocation of bacterial endotoxin.

cDNA-AFLP analysis of plant and pathogen genes expressed in grapevine infected with Plasmopara viticola

Abstract: The oomycete Plasmopara viticola (Berk. and Curt.) Berl. and de Toni causes downy mildew in grapevine (Vitis vinifera L.). This pathogen is strictly biotrophic, thus completely dependent on living host cells for its survival. The molecular basis of compatibility and disease development in this system is poorly understood. We have carried out a large-scale cDNA-AFLP analysis to identify grapevine and P. viticola genes associated with the infection process. We carried out cDNA-AFLP analysis on artificially infected leaves of the susceptible cultivar Riesling at the oil spot stage, on water-treated leaves and on a sample of pure sporangia as controls. Selective amplifications with 128 primer combinations allowed the visualization of about 7000 transcript-derived fragments (TDFs) in infected leaves, 1196 of which (17%) were differentially expressed. We sequenced 984 fragments, 804 of which were identified as grapevine transcripts after homology searching, while 96 were homologous to sequences in Phytophthora spp. databases and were attributed to P. viticola. There were 82 orphan TDFs. Many grapevine genes spanning almost all functional categories were downregulated during infection, especially genes involved in photosynthesis. Grapevine genes homologous to known resistance genes also tended to be repressed, as were several resistance gene analogs and carbonic anhydrase (recently implicated in pathogen resistance). In contrast, genes encoding cytoskeletal components, enzymes of the phenylpropanoid and beta-oxidation pathways, and pathogenesis related proteins were primarily upregulated during infection. The majority of P. viticola transcripts expressed in planta showed homology to genes of unknown function or to genomic Phytophthora sequences, but genes related to metabolism, energy production, transport and signal transduction were also identified. This study provides the first global catalogue of grapevine and P. viticola genes expressed during infection, together with their functional annotations. This will help to elucidate the molecular basis of the infection process and identify genes and chemicals that could help to inhibit the pathogen.

Identification of Lactobacillus reuteri Genes Specifically Induced in the Mouse Gastrointestinal Tract

Abstract: Lactobacilli are common inhabitants of the gastrointestinal tracts of mammals and have received considerable attention due to their putative health-promoting properties. Little is known about the traits that enhance the ability of these bacteria to inhabit the gastrointestinal tract. In this paper we describe the development and application of a strategy based on in vivo expression technology (IVET) that enables detection of Lactobacillus reuteri genes specifically induced in the murine gut. A plasmid-based system was constructed containing 'ermGT (which confers lincomycin resistance) as the primary reporter gene for selection of promoters active in the gastrointestinal tract of mice treated with lincomycin. A second reporter gene, 'bglM (beta-glucanase), allowed differentiation between constitutive and in vivo inducible promoters. The system was successfully tested in vitro and in vivo by using a constitutive promoter. Application of the IVET system with chromosomal DNA of L. reuteri 100-23 and reconstituted lactobacillus-free mice revealed three genes induced specifically during colonization. Two of the sequences showed homology to genes encoding xylose isomerase (xylA) and peptide methionine sulfoxide reductase (msrB), which are involved in nutrient acquisition and stress responses, respectively. The third locus showed homology to the gene encoding a protein whose function is not known. Our IVET system has the potential to identify genes of lactobacilli that have not previously been functionally characterized but which may be essential for growth of these bacteria in the gastrointestinal ecosystem.