Evidence for phospholipid self-organisation in concentrated ammonia-water environments.

Titan, the largest moon of Saturn is thought to have the potential to support primordial life. The surface of Titan contains bodies of liquid hydrocarbons, and modelling suggests that an ammonia-water ocean resides deep beneath the surface, both of which have been speculated to support primordial chemistry. Here we present the first evidence that both preformed and self-organised phospholipid vesicles remain stable and can maintain concentration gradients in ammonia-water environments; a fundamental requirement for primordial chemistry and biology to originate.

Variation in structural motifs within SARS-related coronavirus spike proteins.

SARS-CoV-2 is the third known coronavirus (CoV) that has crossed the animal-human barrier in the last two decades. However, little structural information exists related to the close genetic species within the SARS-related coronaviruses. Here, we present three novel SARS-related CoV spike protein structures solved by single particle cryo-electron microscopy analysis derived from bat (bat SL-CoV WIV1) and civet (cCoV-SZ3, cCoV-007) hosts.

Three-Dimensional Evaluation of the Cytotoxicity and Antibacterial Properties of Alpha Lipoic Acid-Capped Silver Nanoparticle Constructs for Oral Applications.

There is a need to develop bifunctional scaffolds that provide antibacterial protection while encouraging host cell attachment/proliferation. This study evaluates HyStem-C, and photo-cross-linked GelMA hydrogels for encapsulation and stabilisation of silver nanoparticles (AgNPs). We studied the behaviour of AgNPs and matrix interactions within both hydrogel systems.

A lipopolysaccharide-dependent phage infects a pseudomonad phytopathogen and can evolve to evade phage resistance.

Bacterial pathogens are major causes of crop diseases, leading to significant production losses. For instance, kiwifruit canker, caused by the phytopathogen Pseudomonas syringae pv. actinidiae (Psa), has posed a global challenge to kiwifruit production.

Endocytosed silver nanoparticles degrade in lysosomes to form secondary nanoparticle structures during expression of autophagy genes in osteogenic cells.

Silver nanoparticles (AgNPs) are increasingly used in combination with biomaterials, such as bone grafts, to provide antimicrobial properties. Our research focused on the cytotoxic and intracellular uptake mechanism of AgNPs on osteogenic cells, and the affected gene expression of osteoblasts exposed to AgNPs. Osteoblast cells were found to be relatively resistant to AgNP exposure, compared to osteoclasts, with a higher IC and fewer adverse morphological features.

Different genetic and morphological outcomes for phages targeted by single or multiple CRISPR-Cas spacers.

CRISPR-Cas systems provide bacteria and archaea with adaptive immunity against genetic invaders, such as bacteriophages. The systems integrate short sequences from the phage genome into the bacterial CRISPR array. These 'spacers' provide sequence-specific immunity but drive natural selection of evolved phage mutants that escape the CRISPR-Cas defence.

Structural basis for anthrax toxin receptor 1 recognition by Seneca Valley Virus.

Recently, the use of oncolytic viruses in cancer therapy has become a realistic therapeutic option. Seneca Valley Virus (SVV) is a newly discovered picornavirus, which has earned a significant reputation as a potent oncolytic agent. Anthrax toxin receptor 1 (ANTXR1), one of the cellular receptors for the protective antigen secreted by , has been identified as the high-affinity cellular receptor for SVV.

Cryo-Electron Microscopy Structure of Seneca Valley Virus Procapsid.

Seneca Valley virus (SVV), like some other members of the , forms naturally occurring empty capsids, known as procapsids. Procapsids have the same antigenicity as full virions, so they present an interesting possibility for the formation of stable virus-like particles. Interestingly, although SVV is a livestock pathogen, it has also been found to preferentially infect tumor cells and is being explored for use as a therapeutic agent in the treatment of small-cell lung cancers.

CRISPR-Cas gene-editing reveals RsmA and RsmC act through FlhDC to repress the SdhE flavinylation factor and control motility and prodigiosin production in Serratia.

SdhE is required for the flavinylation and activation of succinate dehydrogenase and fumarate reductase (FRD). In addition, SdhE is conserved in proteobacteria (α, β and γ) and eukaryotes. Although the function of this recently characterized family of proteins has been determined, almost nothing is known about how their genes are regulated.

Genome, Proteome and Structure of a T7-Like Bacteriophage of the Kiwifruit Canker Phytopathogen Pseudomonas syringae pv. actinidiae.

Pseudomonas syringae pv. actinidiae is an economically significant pathogen responsible for severe bacterial canker of kiwifruit (Actinidia sp.).

Making EBSD on water ice routine.

Electron backscatter diffraction (EBSD) on ice is a decade old. We have built upon previous work to select and develop methods of sample preparation and analysis that give >90% success rate in obtaining high-quality EBSD maps, for the whole surface area (potentially) of low porosity (<15%) water ice samples, including very fine-grained (<10 μm) and very large (up to 70 mm by 30 mm) samples. We present and explain two new methods of removing frost and providing a damage-free surface for EBSD: pressure cycle sublimation and 'ironing'.

Size exclusion-based purification and PCR-based quantitation of MS2 bacteriophage particles for environmental applications.

MS2 bacteriophage is the most commonly used surrogate for pathogenic viruses in laboratory and field studies. In order to determine the number of infectious viral particles in samples, the use of accurate quantitation methods is essential. We have optimised a size exclusion chromatography-based method for MS2 purification and a SYBR Green-based single-step quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assay for the quantitation of MS2.

Mimicking filtration and transport of rotavirus and adenovirus in sand media using DNA-labeled, protein-coated silica nanoparticles.

Rotavirus (RoV) and adenovirus (AdV) are important viral pathogens for the risk analysis of drinking water. Despite this, little is known about their retention and transport behaviors in porous media due to a lack of representative surrogates. We developed RoV and AdV surrogates by covalently coupling 70-nm sized silica nanoparticles with specific proteins and a DNA marker for sensitive detection.

A Gel Filtration-Based Method for the Purification of Infectious Rotavirus Particles for Environmental Research Applications.

This article describes a rapid method for purifying infectious rotavirus particles from cell culture for environmental research. The method is based on size-exclusion chromatography using TOSOH TSKgel G5000PWXL-CP with a TSKgel Size Exclusion G2500PWxl guard column, set up on an AKTA Explorer10. Four peaks were identified from the chromatogram and the corresponding fractions were collected and analysed by electron microscopy, 1-step quantitative reverse transcription polymerase chain reaction (RT-PCR) and qNano measurement.

In situ ATR-IR spectroscopic and electron microscopic analyses of settlement secretions of Undaria pinnatifida kelp spores.

Knowledge about the settlement of marine organisms on substrates is important for the development of environmentally benign new methods for control of marine biofouling. The adhesion to substrates by spores of Undaria pinnatifida, a kelp species that is invasive to several countries, was studied by scanning electron and transmission electron microscopies (SEM/TEM) as well as by in situ attenuated total reflection infrared (ATR-IR) spectroscopy. The IR spectra showed that adhesive secretion began approximately 15 min after initial settlement and that the adhesive bulk material contained protein and anionic polysaccharides.

Virus-like particles in the ovaries of Microctonus aethiopoides Loan (Hymenoptera: Braconidae): comparison of biotypes from Morocco and Europe.

Virus-like particles (MaVLP) have been discovered in the ovarial epithelial cells of the solitary, koinobiont, endoparasitoid, Microctonus aethiopoides Loan (Hymenoptera: Braconidae) introduced to New Zealand originally from Morocco to control the lucerne pest Sitona discoideus Gyllenhal (Coleoptera: Curculionidae). MaVLP have been found in all females examined. It has been suggested, although not demonstrated, that like many other such VLP found in parasitoids, MaVLP might play a role in host immunosuppression.

Virus-like particles in the ovaries of microctonus aethiopoides loan (Hymenoptera: braconidae), a parasitoid of adult weevils (Coleoptera: curculionidae).

The morphology of the female reproductive system of Microctonus aethiopoides is described and illustrated, and an ultrastructural examination of the ovaries was carried out. Virus-like particles (VLPs) were initially found in the ovarial epithelial cells of females from pre-adult emergence from the pupal cocoon until at least 5 days after emergence. The particles assembled in the nucleus of the epithelial cells, apparently being synthesized de novo in association with a putative virogenic stroma, and they moved into the lumen of the ovarioles surrounding the developing eggs.

Electron microscopic immunocytological profiles in chronic fatigue syndrome.

Structures consistent in size, shape and character with various stages of a Lentivirus replicative cycle were observed by electron microscopy in 12-day peripheral-blood lymphocyte cultures from 10 of 17 Chronic Fatigue Syndrome patients and not in controls. Attempts to identify a lymphoid phenotype containing these structures by immunogold labelling failed and the results of reverse-transcriptase assay of culture supernatants were equivocal. The study was blind and case-controlled, patients being paired with age, sex and ethnically matched healthy volunteers.

Insertional inactivation of the gene encoding a 76-kilodalton cell surface polypeptide in Streptococcus gordonii Challis has a pleiotropic effect on cell surface composition and properties.

A library of Streptococcus gordonii DL1-Challis DNA was constructed in lambda gt11. Phage plaques were screened for production of antigens that reacted with antiserum to S. gordonii cell surface proteins.