High-throughput SNP genotyping of modern and wild emmer wheat for yield and root morphology using a combined association and linkage analysis

Durum wheat (Triticum turgidum var. durum Desf.) is a major world crop that is grown primarily in areas of the world that experience periodic drought, and therefore, breeding climate-resilient durum wheat is a priority. High-throughput single nucleotide polymorphism (SNP) genotyping techniques have greatly increased the power of linkage and association mapping analyses for bread wheat, but as yet there is no durum wheat-specific platform available. In this study, we evaluate the new 384HT Wheat Breeders Array for its usefulness in tetraploid wheat breeding by genotyping a breeding population of F₆ hybrids, derived from multiple crosses between T. durum cultivars and wild and cultivated emmer wheat accessions. Using a combined linkage and association mapping approach, we generated a genetic map including 1345 SNP markers, and identified markers linked to 6 QTLs for coleoptile length (2), heading date (1), anthocyanin accumulation (1) and osmotic stress tolerance (2). We also developed a straightforward approach for combining genetic data from multiple families of limited size that will be useful for evaluating and mapping pre-existing breeding material.     

Cytotoxicity and DNA interactions of some platinum(II) complexes with substituted benzimidazole ligands

In the present study, four Pt(II) complexes with 2-ethyl (1)/or benzyl (2)/or p-chlorobenzyl (3)/or 2-phenoxymethyl (4) benzimidazole carrier ligands were evaluated for their in vitro cytotoxic activities against the human HeLa cervix, oestrogen receptor-positive MCF-7 breast, and oestrogen receptor-negative MDA-MB 231 breast cancer cell lines. The plasmid DNA interactions and inhibition of the BamHI restriction enzyme activities of the complexes were also studied. Complex 3 was found to be more active than carboplatin for all examined cell lines and comparable with cisplatin, except for the HeLa cell line.     

Studies on metal resistance system inKluyveromyces marxianus

Through preliminary plate tests,Kluyveromyces marxianus was found to be much more resistant to toxic heavy metals compared to aCUP1 ^R strain ofSaccharomyces cerevisiae. Specific growth rate and maximum dry weights affected by increasing metal concentrations were determined to obtain precise patterns of resistance. Metal biosorption was also monitored during the course of growth in synthetic media containing respective metals at 0.5 mM final concentration. Although Zn- and Co-binding was negligible, as much as 90% of silver, 60% of copper, and 65% of cadmium were found to be absorbed by the end of active growth. Analysis of the protein profiles ofS. cerevisiae andK. marxianus on metal exposure suggested constitutive production of metallothionein inK. marxianus. Furthermore, a smaller protein synthesized byK. marxianus on induction by silver or cadmium accounts for the high resistance of the organism to these metals.     

Efficacy of a quaternary ammonium compound against planktonic and sessile populations of differentLegionella pneumophila strains

Efficacy of Gemacide PN-50^TM (a quaternary ammonium compound) as a commercial formulation recommended for disinfecting heat exchangers was determined for both planktonic and sessile populations of variousLegionella pneumophila strains. The quaternary ammonium compound (QAC) was preferred as an alternative due to the emerging resistance of potentially pathogenic bacteria against different biocides. PlanktonicL. pneumophila strains were suspended in tap water while sessile ones were grown on stainless steel that is used in construction of the cooling towers, then both group of strains were exposed to the biocide. The sensitivity of both planktonic and sessile populations ofL. pneumophila strains to the biocide was different. The biocide was found effective below recommended dosages (1000–2000 mg/L) against planktonic populations ofL. pneumophila, whereas it was determined that higher than the recommended dosages were required for sessile populations. The environmental isolates were more resistant to the biocide than the ATCC isolate was. The results indicated that studying only the planktonic populations ofL. pneumophila for biocide tests might not be sufficient to provide the optimum dosage and contact time information for field trials. Therefore, biocidal activity of a water treatment chemical must be evaluated in terms of dosage and contact times on both planktonic and sessile bacteria.     

In vitro labeling of hydroxyapatite minerals by an engineered protein

Biological and biomimetic synthesis of inorganics have been a major focus in hard tissue engineering as well as in green processing of advanced materials. Among the minerals formed by organisms, calcium phosphate mineralization is studied extensively to understand the formation of mineral-rich tissues. Herein, we report an engineered fusion protein that not only targets calcium phosphate minerals but also allows monitoring of biomineralization. To produce the bi-functional fusion protein, nucleotide sequence encoding combinatorially selected hydroxyapatite-binding peptides (HABP) was genetically linked to the 3' end of the open reading frame of green fluorescence protein (GFPuv) and successfully expressed in Escherichia coli. The fluorescence and binding activities of the bi-functional proteins were characterized by, respectively, using fluorescence microscopy and quartz crystal microbalance spectroscopy. The utility of GFPuv-HABP fusion protein was assessed for both time-wise monitoring of mineralization and the visualization of the mineralized tissues. We used an alkaline phosphatase-based reaction to control phosphate release, thereby mimicking biological processes, to monitor calcium phosphate mineralization. The increase in mineral amount was observed using the fusion protein at different time points. GFPuv-HABP1 was also used for efficient fluorescence labeling of mineralized regions on the extracted human incisors. Our results demonstrate a simple and versatile application of inorganic-binding peptides conjugated with bioluminescence proteins as bi-functional bioimaging molecular probes that target mineralization, and which can be employed to a wide range of biomimetic processing and cell-free tissue engineering.     

Immobilization of lipases on different carriers and their use in synthesis of pentyl isovalerates

Porcine pancreatic lipase (PPL) and Candida cylindracea lipase (CCL) were immobilized on Celite and Amberlite IRA 938 by deposition from the aqueous solution by the addition of hexane. The influence of the immobilization on the activities of the immobilized lipase derivatives has been studied. The immobilized lipases were used in synthesis of pentyl isovalerates. Various reaction parameters affecting the synthesis of pentyl isovalerates were investigated. The reaction rates were compared with the rates of esterification with free lipases. The immobilized lipases were found to be very effective in the esterification reaction. The lipases immobilized on Celite 545 exhibited better operational stabilities than that of immobilized on Amberlite IRA-938.     

Global regulatory systems operating in Bacilysin biosynthesis in Bacillus subtilis

In Bacillus subtilis, bacilysin is a nonribosomally synthesized dipeptide antibiotic composed of L-alanine and L-anticapsin. The biosynthesis of bacilysin depends on the bacABCDEywfG operon (bac operon)and the adjacent ywfH gene. To elucidate the effects of global regulatory genes on the expression of bac operon, we used the combination of lacZ fusion analysis and the gel mobility shift assays. The cell density-dependent transition state induction of the bac operon was clearly shown. The basal expression level of the bac operon as well as transition state induction of bac is directly ComA dependent. Three Phr peptides, PhrC, PhrF and PhrK, are required for full-level expression of ComA-dependent bac operon expression, but the most important role seemed to be played by PhrC in stimulating bac expression through a RapC-independent manner. Spo0A is another positive regulator which participates in the transition state induction of bac both directly by interacting with the bac promoter and indirectly by repressing abrB expression. AbrB and CodY proteins do not only directly repress the bac promoter, but they also mutually stimulate the transition state induction of bac indirectly, most likely by antagonizing their repressive effects without preventing each other's binding since both proteins can bind to the bac promoter simultaneously.     

A new species of Scorzonera (Asteraceae) from Anatolia, Turkey

Scorzonera aytatchii sp. nov. is described from the Aydos Mountain (C4: Konya) in Turkey. It is related to S. rigida , from which it mainly differs in its hairy achene.