Abstract The genomic diversity of many fungal species is augmented by accessory chromosomes, which are variably present in individual strains. These genomic regions evolve rapidly, accumulating genes important in pathogenicity but also harboring significant amounts of transposable elements (TEs). This duality suggests a trade-off: accessory chromosomes provide infection-related benefits while otherwise being deleterious due to their highly repetitive nature and contributions to genomic instability. Despite this, accessory chromosomes often appear to be stably maintained even when strains are grown on media, with no plant host. Previously, we had observed that genes homologous to meiotic drive toxin/antidote proteins from Podospora anserina ( Spoks ) are abundant on accessory chromosomes in various Fusarium species. Using a functionality screen in yeast, we demonstrate that some of these homologs have active toxin and antidote properties. We propose that these selfish genes act to maintain accessory chromosomes during vegetative growth and may influence their spread via parasexual cycles. Finally, as Spok genes are mobilized by the newly described TE superfamily Starships , it suggests these TEs play crucial roles in forming accessory chromosomes and regions. These results illuminate a mysterious facet of fungal biology, a key step towards describing the origin, spread, and maintenance of pathogenicity in many fungal species.
Abstract Short tandem repeat (STR) loci are routinely employed for individual identification. We have examined the performance and reproductibility of a highly informative co‐amplification system containing the tetranucleotide STR loci: HUMVWFA31/A, HUMTH01, D20S85, D8S1179, HUMFIBRA, D21S11, and D18S51, in conjunction with the amelogenin sex test, in addition to a modified system omitting the locus D20S85. Polymerase chain reaction (PCR) products were fluorescently detected on an automated sequencer and automatically sized against an internal size standard by Genescan software. Both systems were routinely able to type 500 pg of undegraded DNA. At DNA concentrations between 50–500 pg, partial profiles were produced, but no allelic drop‐out was observed. Balanced amplification of all loci occurred over a wide range of DNA concentrations from 50 pg to 10 ng. Alteration of reagent concentrations and cycling parameters from optimal resulted in variation in the efficiency of individual locus amplification relative to the other loci within the system. This was also observed at high ionic strength or extreme pH. However, at all reagent concentrations and conditions, allelic drop‐out was not observed. These multiplex systems have potential in both routine forensic and intelligence database applications.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract Here, we report the use of fluorescently labelled proteins to study protein adsorption to microarrayed synthetic polymers for the first time, indicating that this method is appropriate for the study of protein adsorption on these arrays. To investigate protein adhesion directly we use atomic force microscopy (AFM) to measure the force of adhesion between a protein‐coated probe and the arrayed polymers. Both approaches show promise as methods for screening protein interactions with polymers in a microarray format. Comparison of these very different measures of protein–surface interactions indicate a good correlation. magnified image
Cyclosporine (CyA) solid lipid nanoparticles were prepared by using a solvent free high pressure homogenization process. CyA was incorporated into SLNs that consisted of stearic acid, trilaurin or tripalmitin lipid solid cores in order to enhance drug solubility. The process was conducted by varying lipid compositions, drug initial loading and applied homogenization pressure. The processing temperatures were above the lipid melting points for all formulations. The empty and CyA loaded SLN particles made were characterized for particle size stability over six months. Atomic force microscopy (AFM) and photon correlation spectroscopy (PCS) showed particle sizes ranging from 112-177 nm for empty and 181-215 nm for loaded SLNs each with narrow particle size distributions. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques were used to characterize the CyA state, which was found to be amorphous, within the lipid cores of freeze-dried SLNs. The CyA metastable form showed a profound effect on the drug dissolution rates. SLNs were incubated in Caco-2 cells for 24 hr showing negligible cell cytotoxicity up to 15 mg/ml.
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)
