University of Alcalá

About: University of Alcalá is a education organization based out in Alcalá de Henares, Spain. It is known for research contribution in the topics: Population & Receptor. The organization has 10795 authors who have published 20718 publications receiving 410089 citations. The organization is also known as: University of Alcala & University of Alcala de Henares.

Molecular characterisation of the inactive allele of the gene Glu-A1 and the development of a set of AS-PCR markers for HMW glutenins of wheat

Abstract: The present work reports new PCR markers that amplify the complete coding sequence of the specific alleles of the high molecular weight (HMW) glutenin genes. A set of AS-PCR molecular markers was designed which use primers from nucleotide sequences of the Glu-A1 and Glu-D1 genes, making use of the minor diffeences between the sequences of the x1, x2* of Glu-A1, and the x5 and y10 of Glu-D1. These primers were able to distinguish between x2* and the x1 or xNull of Glu-A1. Also x5 was distinguishable from x2, and y10 from y12. The primers amplified the complete coding regions and corresponded to the upstream and downstream flanking positions of Glu-A1 and Glu-D1. Primers designed to amplify the Glu-A1 gene amplified a single product when used with genomic DNA of common wheats and the xNull allele of this gene. This work also describes the cloning and characterisation of the nucleotide sequence of this allele. It possesses the same general structure as x2* and x1 (previously determined) and differs from these alleles in the extension of the coding sequence for a presumptive mature protein with only 384 residues. This is due to the presence of a stop codon (TAA) 1215-bp downstream from the start codon. A further stop codon (TAG), 2280-bp downstream from the starting codon is also found. The open reading frame of xNull and x1 alleles has the same size in bp. Both are larger than x2* which shows two small deletions. The reduced size of the presumptive mature protein encoded by xNull could explain the negative effect of this allele on grain quality.

Turnover Numbers and Soluble Metal Nanoparticles

Abstract: The catalytic activity expressed by turnover number (TON) and turnover frequency (TOF) in different fields of catalysis (enzymatic, homogeneous (single‐site), heterogeneous (multi‐site), and nanocatalysis (oligo‐site)) are usually estimated in slightly different ways and with slightly different, yet important meanings. For soluble metal nanoparticles, the ideal is to determine the TON by using the titrated number of active catalytic sites before the catalyst is inactivated. However, in the absence of reliable titration methods it is suggested that TON figures should always be reported as the number of moles of reactants consumed per mol of soluble metal catalyst, and that they should also be corrected by the number of exposed surface atoms by using the metal atom’s magic number approach. Moreover, it is strongly recommended that the TOF should be determined from the slope of plots of turnover numbers versus time, because in various cases the size and shape of the soluble nanoparticles might change dramatically during the reaction. As in organometallic catalysis, in the absence of TON vs. time data, the TOF should be estimated for low substrate conversions.