The levels of the mRNAs for light-inducible, nuclear-coded chloroplast proteins vary rhythmically in pea (Pisum sativum L.) plants either grown in a dark-light cycle or under constant light conditions. This has been observed for the early light-inducible protein, the light-harvesting chlorophyll a/b protein, and the small subunit of the ribulose-1,5-bisphosphate carboxylase. The mRNA levels are high in the morning, exhibit a minimum in the first half of the night, and increase again during the second half of the night. The amplitude of fluctuation is between 5-and 10-fold. A similar change in the mRNA abundance was found for four nuclear encoded heat-shock proteins of 18, 24, 26, and 30 kilodaltons. The ability of plants to transcribe heat-shock genes upon heat-shock for 2 hours varies through the day. The maxima for induction are found in the second half of the night and the morning. The minima are reached during the afternoon. The degree of fluctuation is between 3-and 5-fold. The levels of mRNAs for cytosolic as well as for plastid heat-shock proteins oscillate in parallel.

A cDNA clone, pCHS62, was isolated using poly(A)-rich RNA from heat-shocked Chlumydomonus reinhurdtii cells. The clone has a length of 1.1 kb and codes for the complete heat-shock protein which was reported to be associated with the grana region of the thylakoid membranes and ascribes protection against photoinhibition during heat-shock. An expression vector prepared in the pUC19 plasmid was used to obtain a fusion protein against which rabbit polyclonal antibodies have been raised. The antibodies react specifically with the heat-shock protein of 22 kDa synthesized in vivo during heat-shock, which is localized in the grana thylakoids, with the in vitro translated product using poly(A)-rich RNA from heat-treated cells as well as with the hybrid release translation product of the pCHS62 clone. The clone was sequenced. It contains a 5' region consisting of 85 nucleotides, an open reading frame of 471 nucleotides and a non-coding 3' region of 600 nucleotides. Northern hybridization indicates a length of 1.7 kb for the messenger RNA of heat-shock protein 22. Analysis of similarity between the derived amino acid sequence of this protein and other heat-shock proteins demonstrates that this protein belongs to the small-molecular-mass plant heat-shock protein family and also shows similarities with animal heat-shock proteins including the presence of a short region possessing similarity with bovine a-crystalline as reported for other heat-shock proteins. The molecular mass of the protein as determined from the sequence is 16.8 kDa. Despite its localization in the chloroplast membranes, it does not seem to include a transit peptide sequence, in agreement with previous data. The sequence contains only a short hydrophobic region compatible with its previously reported localization as a thylakoid extrinsic protein.In response to a sudden elevation of temperature, a number of specific genes, termed heat-shock genes, are activated in both procaryotic and eucaryotic cells [ 11. Following induction, a rapid transcription and preferential translation of the corresponding heat-shock mRNAs takes place and results in a significant accumulation of the heat-shock proteins [2]. In accordance with the universality of the heat-shock response, a relatively high degree of similarity characterizes heat-shock proteins from various organisms. In higher plants smallmolecular-mass heat-shock proteins (1 5 -30 kDa) represent a particularly prominent and heterogeneous group of proteins coded by multigene families [3 -61. The complexity and the diversity in the sizes of the low-molecular-mass heat-shock proteins seem to indicate a lower degree of similarity, in contrast to the high degree of conservation in the amino acid sequences of the high-molecular-mass heat-shock proteins common to both the plant and animal kingdoms. Like their high-molecular-mass counterparts, the small heat-shock proteins in plants are nuclear-coded and translated on cytosolic ribosomes. The majority of them remain in the cytosol and become associated with the cytoskeleton...

Fluorescent staining techniques were used to study the anti-microbial properties of aqueous suspensions of a novel, water insoluble amino functionalised polymer on three micro-organisms Pseudomonas fluorescens, Staphylococcus epidermidis and Saccharomyses cerevisiae. The mechanism of action was similar for each organism in that, after various contact times with the polymer, a progressive change in individual cell physiological state was measured using multi-parameter flow cytometry. The microbiocidal activity of this polymer may be similar to that of substances referred to as polycationic, amphipathic compounds (peptides, peptide derivatives and other polyamines).

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Nanomaterialien und ultradünne Beschichtungen von Nanopartikeln werden die Eigenschaften vieler künftiger Produkte bestimmen: Ultraharte Oberflächen, superschnelle Computer, schmutzabweisende Oberflächen, neuartige Krebsbehandlungsmethoden, kratzfeste Beschichtungen, preiswerte Solarzellen, preiswerte Displays und druckbare Elektronik. Der Markt für Nanotechnologieprodukte wächst zweistellig und wird im Jahr 2010 mehrere hundert Millarden US‐Dollar betragen.