Prey range and genome evolution of Halobacteriovorax marinus predatory bacteria from an estuary

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in mSphere 3 (2018): e00508-17, doi:10.1128/mSphere.00508-17.Halobacteriovorax strains are saltwater-adapted predatory bacteria that attack Gram-negative bacteria and may play an important role in shaping microbial communities. To understand how Halobacteriovorax strains impact ecosystems and develop them as biocontrol agents, it is important to characterize variation in predation phenotypes and investigate Halobacteriovorax genome evolution. We isolated Halobacteriovorax marinus BE01 from an estuary in Rhode Island using Vibrio from the same site as prey. Small, fast-moving, attack-phase BE01 cells attach to and invade prey cells, consistent with the intraperiplasmic predation strategy of the H. marinus type strain, SJ. BE01 is a prey generalist, forming plaques on Vibrio strains from the estuary, Pseudomonas from soil, and Escherichia coli. Genome analysis revealed extremely high conservation of gene order and amino acid sequences between BE01 and SJ, suggesting strong selective pressure to maintain the genome in this H. marinus lineage. Despite this, we identified two regions of gene content difference that likely resulted from horizontal gene transfer. Analysis of modal codon usage frequencies supports the hypothesis that these regions were acquired from bacteria with different codon usage biases than H. marinus. In one of these regions, BE01 and SJ carry different genes associated with mobile genetic elements. Acquired functions in BE01 include the dnd operon, which encodes a pathway for DNA modification, and a suite of genes involved in membrane synthesis and regulation of gene expression that was likely acquired from another Halobacteriovorax lineage. This analysis provides further evidence that horizontal gene transfer plays an important role in genome evolution in predatory bacteria.This research was supported by an Institutional Development award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant no. P20GM103430 and funding from Providence College

Female domestic violence counsellors/psychotherapists: attitudes towards addiction. An interpretative phenomenological analysis

Many counsellors/psychotherapists working with victims of domestic violence (DV) encounter substance use disorders (SUDs), whether directly or indirectly, and yet an understanding of how to address these co-occurring issues in practice appears lacking. A qualitative design using semi-structured interviews and IPA captured the individual experiences and perceptions of 6 female BACP registered counsellors/psychotherapists who counsel victims of DV based in DV ‘specific’ organisations. Four super-ordinate themes emerged and included a ‘feminist perspective’, ‘addiction: symptom of trauma’, ‘skills development in substance misuse’ and ‘feelings of exclusion in the workplace’. This study offers an initial understanding of how DV counsellors view SUDs and the impact this had in their practice. It further provided insight into how supported and involved they felt in their workplace when counselling this group. These findings are discussed in terms of strategy development and training aimed at improving the experience of counsellors/psychotherapists working in DV counselling organisations when they encounter SUDs in order to support counsellors and service-users well-being

Using remote sensing to track complex sinuous ripple migration on a barchan dune in Herschel Crater, Mars

Dunes on Mars are known to migrate, in particular ripples have also been found to migrate. This is known to have occurred in eastern, western and southern Herschel Crater, but it was not known if this was true for Central Herschel Crater. Central Herschel Crater is of particular interest as the dunes found there were deemed indurated. However, since the release of HiRISE (2023) satellite images it is clear that these dunes are in fact very much the opposite. These dunes were actively migrating and presented some unique superimposed ripples. With this, we set out to measure the migration of both the superimposed ripples and the dune itself. The results indicate a ripple migration of between 0.12 m/Earth year and 0.61 m/Earth year, and a dune migration rate of approximately 4.2 m/Earth year. Moreover, the dunes and ripples have been influenced by a predominant wind direction from the north. This new knowledge is important since it provides more information on Mars’ climate, the migration of dunes and ripples on Mars, and how to apply a new method of quantifying ripple migration for an efficient and quick analysis of the large amount of data that HiRISE has to offer for future research. Furthermore, this information can assist further research and decision making for potential future landing sites on Mars

Reducing the Impact of Disabilities in Developing Nations: Implications from a Parent Delivered Behavioral Intervention in Macedonia

Autism spectrum disorder (ASD) is recognized the world over as a major public health issue. Autism is highly prevalent, persists across the lifespan, and is characterized by behaviors that can profoundly impair typical functioning. Interventions based on behavioral strategies have proven effective, but there are significant barriers to care, including cost, intensity of treatment, and access to qualified practitioners. The impact of ASD and obstacles to appropriate care are magnified by systemic limitations in developing countries. Parent training holds promise as a method of disseminating therapy to underserved areas. This study investigated the effectiveness of a pyramidal parent training intervention in Macedonia. Fifteen parents of children with ASD were trained in three specific strategies for promoting prosocial skills: eye contact, compliance, reducing restricted repetitive behaviors (RRB). Parents reported daily ratings of these skills and their own confidence, action or engagement, and family distress. Participants were ethnic Macedonians from the capital of Skopje with at least one child with ASD between the ages of 2 and 13 years. This study utilized a single case research design. Data were collected per and post intervention using an interrupted time series design. Individual response was analyzed visually and Tau U effect sizes were calculated. Moderator and mediator effect was considered following the method initially established by Gaynor and Harris (2008). Effect sizes were small but significant for the group overall for all variables except restricted repetitive behaviors (RRB). The program was especially effective for younger children, those with comorbid hyperactivity, those with low to moderate symptomology, and those with no prior special education services

(p)ppGpp-Dependent Persisters Increase the Fitness of Escherichia coli Bacteria Deficient in Isoaspartyl Protein Repair

ABSTRACT The l -isoaspartyl protein carboxyl methyltransferase (PCM) repairs protein damage resulting from spontaneous conversion of aspartyl or asparaginyl residues to isoaspartate and increases long-term stationary-phase survival of Escherichia coli under stress. In the course of studies intended to examine PCM function in metabolically inactive cells, we identified pcm as a gene whose mutation influences the formation of ofloxacin-tolerant persisters. Specifically, a Δ pcm mutant produced persisters for an extended period in stationary phase, and a Δ glpD mutation drastically increased persisters in a Δ pcm background, reaching 23% of viable cells. The high-persister double mutant showed much higher competitive fitness than the pcm mutant in competition with wild type during long-term stationary phase, suggesting a link between persistence and the mitigation of unrepaired protein damage. We hypothesized that reduced metabolism in the high-persister strain might retard protein damage but observed no gross differences in metabolism relative to wild-type or single-mutant strains. However, methylglyoxal, which accumulates in glpD mutants, also increased fitness, suggesting a possible mechanism. High-level persister formation in the Δ pcm Δ glpD mutant was dependent on guanosine pentaphosphate [(p)ppGpp] and polyphosphate. In contrast, persister formation in the Δ pcm mutant was (p)ppGpp independent and thus may occur by a distinct pathway. We also observed an increase in conformationally unstable proteins in the high-persister strain and discuss this as a possible trigger for persistence as a response to unrepaired protein damage. IMPORTANCE Protein damage is an important factor in the survival and function of cells and organisms. One specific form of protein damage, the formation of the abnormal amino acid isoaspartate, can be repaired by a nearly universally conserved enzyme, PCM. PCM-directed repair is associated with stress survival and longevity in bacteria, insects, worms, plants, mice, and humans, but much remains to be learned about the specific effects of protein damage and repair. This paper identifies an unexpected connection between isoaspartyl protein damage and persisters, subpopulations in bacterial cultures showing increased tolerance to antibiotics. In the absence of PCM, the persister population in Escherichia coli bacteria increased, especially if the metabolic gene glpD was also mutated. High levels of persisters in pcm glpD double mutants correlated with increased fitness of the bacteria in a competition assay, and the fitness was dependent on the signal molecule (p)ppGpp; this may represent an alternative pathway for responding to protein damage