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.

Zinc and Iron Concentrations in Seeds of Wild, Primitive, and Modern Wheats

Abstract: In the case of cultivated modern wheats, the variation in zinc and iron concentrations in seeds is relatively small. Moreover, environmental and management factors exert a greater effect on variation of micronutrient concentrations of modern cultivated wheats than genetic factors. Wild wheats might serve as an important source of new genetic material for increasing micronutrient concentrations in seeds. To investigate this, we studied the variation in zinc and iron concentrations in seeds of wild and primitive diploid wheats and wild tetraploid wheats. The variation was particularly large in the case of zinc. The highest concentrations of zinc were found in the seeds of ssp. boeoticum (178 mg/kg) and ssp. dicoccoides (159 mg/kg). The results demonstrate that the genetic variation in the concentrations of zinc and iron in cultivated modern tetraploid and hexaploid wheats is extremely low when compared with the variation found in wild diploid and tetraploid wheats. This suggests that wild wheats, particular...

Characterization of Lactobacillus coryniformis DSM 20001T Surface Protein Cpf Mediating Coaggregation with and Aggregation among Pathogens

Abstract: Phenotypic characterization of aggregation phenotypes of Lactobacillus coryniformis revealed that strain DSM 20001T coaggregated with Escherichia coli K88, Campylobacter coli, and Campylobacter jejuni but not with other human pathogens. In addition, cells of these pathogens aggregated in the presence of the spent culture supernatant (SCS) of strain DSM 20001T. Cells of E. coli K88 remained viable in the coaggregates and aggregates for up to 24 h. Both coaggregation and aggregation (co/aggregation) occurred at pH 3.5 to 7.5 and was sensitive to heat (85 degrees C for 15 min) and proteinase K. The co/aggregation-promoting factor (Cpf) was purified, and the gene was identified by PCR with degenerate primers derived from internal amino acid sequences. The cpf gene encoded a 19.9-kDa preprotein with a sec-dependent leader and an isoelectric point of 4.4. The amino acid sequence had no significant similarity to proteins with known functions. Northern analysis revealed not only major transcription from the promoter of cpf but also major transcription from the promoter of the preceding insertion element, ISLco1 belonging to the IS3 family. Recombinant Cpf produced in E. coli mediated aggregation of pathogens comparable to the aggregation obtained with purified Cpf or SCS of strain DSM 20001T. Cpf could be removed from cells of strain DSM 20001T by treatment with 5 M LiCl and could be subsequently reattached to the cell surface by using SCS or recombinant Cpf, which resulted in restoration of the co/aggregation property. These results together with those of the amino acid sequence analysis suggest that Cpf is a novel surface protein of L. coryniformis that mediates co/aggregation of some pathogens.