We suggest that proIAPP forms the first amyloid fibrils and that this can occur already in the secretory granules of the beta cells. The proIAPP-derived fibrils can act as seed for further amyloid formation, now made up by IAPP. The observed difference between human islet transplants and human IAPP transgenic animals may reflect differences in stages of amyloid development.

No abstract

The amount and size distribution of polymeric protein, environmentally influenced by temperature and nitrogen timing, is an important factor determining gluten strength in wheat. Differences in mature wheat might be explained by alterations in accumulation and build-up of proteins in the developing wheat grain. One cultivar was grown to maturity in a greenhouse using two temperatures and four nitrogen regimes. Plants were harvested during grain development and protein compositions were determined. Proteins were accumulated and built up similarly independent of temperature and nitrogen regime. Temperature influenced the protein concentration significantly, for all protein types throughout the grain development period and at maturity. The time for increase in amount of polymeric proteins differed with temperature if time was measured as days after anthesis, but not if time was measured as degree-days. Different temperature regimes did not generally result in changes in amount and size distribution of polymeric protein. The combination of lower temperature, different nitrogen regimes and one of the cultivations led to changes in the amount and size distribution of polymeric protein in mature grains. These differences were due to a change in amount of SDS-extractable polymeric and large monomeric proteins during grain development, indicating influences on disulphide bond formation.

No abstract

In Sweden, human cases of tularemia caused by Francisella tularensis holarctica are assumed to be transmitted by mosquitoes, but how mosquito vectors acquire and transmit the bacterium is not clear. To determine how transmission of this bacterium occurs, mosquito larvae were collected in an area where tularemia is endemic, brought to the laboratory, and reared to adults in their original pond water. Screening of adult mosquitoes by real-time PCR demonstrated F. tularensis lpnA sequences in 14 of the 48 mosquito pools tested; lpnA sequences were demonstrated in 6 of 9 identified mosquito species. Further analysis confirmed the presence of F. tularensis holarctica–specific 30-bp deletion region sequences (FtM19inDel) in water from breeding containers and in 3 mosquito species (Aedes sticticus, Ae. vexans, and Ae. punctor) known to take blood from humans. Our results suggest that the mosquitoes that transmit F. tularensis holarctica during tularemia outbreaks acquire the bacterium already as larvae.