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Capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) were applied to the simultaneous separation of cyanobacterial toxins (anatoxin-a, microcystin-LR, cylindrospermopsin). The analytical performance data of both methods, optimized for the three toxins, were similar with a precision of migration times smaller than 0.8 RSD% and a detection limit in the range of 1-4 microg/mL, using spectrophotometric detection at 230 nm. Both methods were applied to an analysis of cyanotoxins in water bloom samples and crude cyanobacterial extracts. The results obtained indicate that, for complex matrices, the sequential application of CZE and MEKC is necessary. It is recommended to use both CE techniques for the analysis of the same sample in order to confirm the results by an orthogonal approach.

123 Genet Resour Crop Evol (2011) 58:125-137 DOI 10.1007/s10722 -010-9601-5 currently consists of 220 accessions from 15 countries: 169 of these come from European cultivation countries, 18 from commercial areas in non EU countries, 26 from regions of minimal or relict production and/or from abandoned fields and 7 from commercial nurseries. The non-saffron Crocus collection currently comprises 352 accessions: 179 collected from the wild in 12 countries of natural distribution, 24 from donations of public and private institutions, 91 from commercial nurseries and 58 acquired from BGV-CU collection management. Here we provide a record of collections, activities concerns and current strategies for documentation, conservation, characterisation, and management of the collection as important tools for researchers with interest in these valuable genetic resources.

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The rate of total RNA synthesis, the extent of guanosine 3'(2')-diphosphate 5 '-diphosphate (ppGpp) accumulation, and the pattern of protein synthesis were studied in light-deprived and heat-shocked Synechococcus sp. strain PCC 6301 cells. There was an inverse correlation between the rate of total RNA synthesis and the pool size of ppGpp, except immediately after a temperature shift up, when a parallel increase in the rate of RNA synthesis and accumulation of ppGpp was observed. The inverse correlation between RNA synthesis and ppGpp accumulation was more pronounced when cells were grown in the dark. Heat shock treatment (47°C) had an unexpected effect on ppGpp accumulation; there was a fairly stable level of ppGpp under heat shock conditions, which coincided with a stable steady-state rate of RNA synthesis even in the dark. We found that the pattern of dark-specific proteins was altered in response to heat shock. The transient synthesis of several dark-specific proteins was abolished by an elevated temperature (47C) in the dark; moreover, the main heat shock proteins were synthesized even in the dark. This phenomenon might be of aid in the study of cyanobacterial gene expression.

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