bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phospholipase Dα1 acts as a negative regulator of high Mg2+-induced leaf senescence in Arabidopsis
Authors: Kocourková Daniela , Kroumanová Kristýna , Podmanická Tereza , Daněk Michal , Martinec Jan 
Published: August 2021

AbstractMagnesium is a macronutrient involved in essential cellular processes. Its deficiency or excess is a stress factor for plants, seriously affecting their growth and development and therefore, its accurate regulation is essential. Recently, we discovered that phospholipase Dα1 (PLDα1) activity is vital in the stress response to high-magnesium conditions in Arabidopsis roots. This study shows that PLDα1 acts as a negative regulator of high-Mg2+-induced leaf senescence in Arabidopsis. The level of phosphatidic acid produced by PLDα1 and the amount of PLDα1 in the leaves increase in plants treated with high Mg2+. A knockout mutant of PLDα1 (plda1-1), exhibits premature leaf senescence under high-Mg2+ conditions. In pldα1-1 plants, higher accumulation of abscisic and jasmonic acid and impaired magnesium, potassium and phosphate homeostasis were observed under high-Mg2+ conditions. High Mg2+ also led to an increase of starch and proline content in Arabidopsis plants. While the starch content was higher in plda1-1 plants, proline content was significantly lower in plda1-1 compared with WT. Our results show that PLDα1 is essential for Arabidopsis plants to cope with the pleiotropic effects of high-Mg2+ stress and delay the leaf senescence.
A modular platform for on-demand vaccine self-assembly enabled by decoration of bacterial outer membrane vesicles with biotinylated antigens
Authors: Weyant Kevin B. , Liao Julie , Jesus Mariela Rivera-De , Jaroentomeechai Thapakorn , Moeller Tyler D. , Hoang-Phou Steven , Pal Sukumar , Gilmore Sean F. , Singh Riya , Putnam David , Locher Christopher , de la Maza Luis M. , Coleman Matthew A. , DeLisa Matthew P. 
Published: August 2021

AbstractEngineered outer membrane vesicles (OMVs) derived from laboratory strains of bacteria are a promising technology for the creation of non-infectious, nanoparticle vaccines against diverse pathogens. As mimics of the bacterial cell surface, OMVs offer a molecularly-defined architecture for programming repetitive, high-density display of heterologous antigens in conformations that elicit strong B and T cell immune responses. However, antigen display on the surface of OMVs can be difficult to control and highly variable due to bottlenecks in protein expression and localization to the outer membrane of the host cell, especially for bulky and/or complex antigens. To address this shortcoming, we created a universal approach called AddVax (avidin-based dock- and-display for vaccine antigen cross (x)-linking) whereby virtually any antigen that is amenable to biotinylation can be linked to the exterior of OMVs whose surfaces are remodeled with multiple copies of a synthetic antigen receptor (SNARE) comprised of an outer membrane scaffold protein fused to a member of the avidin family. We show that SNARE-OMVs can be readily decorated with a molecularly diverse array of biotinylated subunit antigens, including globular and membrane proteins, glycans and glycoconjugates, haptens, lipids, and short peptides. When the resulting OMV formulations were injected in wild-type BALB/c mice, strong antigen-specific antibody responses were observed that depended on the physical coupling between the antigen and SNARE-OMV delivery vehicle. Overall, these results demonstrate AddVax as a modular platform for rapid self-assembly of antigen-studded OMVs with the potential to accelerate vaccine generation, respond rapidly to pathogen threats in humans and animals, and simplify vaccine stockpiling.
Cryo-EM structures reveal multiple stages of bacterial outer membrane protein folding
Authors: Doyle Matthew Thomas , Jimah John R. , Hinshaw Jenny E. , Bernstein Harris D. 
Published: August 2021

SUMMARYTransmembrane β-barrel proteins are folded into the outer membrane (OM) of Gram-negative bacteria by the β-barrel assembly machine (BAM) via an unexplained process that occurs without known external energy sources. Here we used single-particle cryo-EM to visualize the folding dynamics of a model β-barrel protein (EspP) by BAM. We found that BAM binds the highly conserved “β-signal” motif of EspP to correctly orient β-strands in the OM during folding. We also found that the folding of EspP proceeds via remarkable “hybrid-barrel” intermediates in which membrane integrated β-sheets are attached to the essential BAM subunit, BamA. The structures show an unprecedented deflection of the membrane surrounding the EspP intermediates and suggest that β-sheets progressively fold towards BamA to form a β-barrel. Along with in vivo experiments that tracked β-barrel folding while the OM tension was modified, our results support a model in which BAM harnesses OM elasticity to accelerate β-barrel folding.
Neutrophil-associated responses to Vibrio cholerae infection in a natural host model
Authors: Farr Dustin , Nag Dhrubajyoti , Chazin Walter J. , Harrison Simone , Thummel Ryan , Luo Xixia , Raychaudhuri Saumya , Withey Jeffrey H. 
Published: August 2021

AbstractVibrio cholerae, the cause of human cholera, is an aquatic bacterium found in association with a variety of animals in the environment, including many teleost fish species. V. cholerae infection induces a pro-inflammatory response followed by a non-inflammatory convalescent phase. Neutrophils are integral to this early immune response. However, the relationship between the neutrophil-associated protein calprotectin and V. cholerae has not been investigated, nor have the effects of limiting transition metals on V. cholerae growth. Zebrafish are useful as a natural V. cholerae model as the entire infectious cycle can be recapitulated in the presence of an intact intestinal microbiome and mature immune responses. Here, we demonstrate that zebrafish produce a significant neutrophil, IL-8, and calprotectin response following V. cholerae infection. Bacterial growth was completely inhibited by purified calprotectin protein or the chemical chelator TPEN, but growth was recovered by addition of transition metals zinc and manganese. Expression of downstream calprotectin targets also significantly increased in the zebrafish. These findings are the first to illuminate the role of calprotectin and nutritional immunity in combating V. cholerae infection. Inhibition of V. cholerae growth through metal limitation may provide new approaches in the development of anti-V. cholerae therapeutics. This study also establishes a major role for calprotectin in combating infectious diseases in zebrafish.
Production and composition of group B streptococcal membrane vesicles varies across diverse lineages
Authors: McCutcheon Cole R. , Gaddy Jennifer A. , Aronoff David M. , Petroff Margaret G. , Manning Shannon D. 
Published: August 2021

ABSTRACTAlthough the neonatal and fetal pathogen Group B Streptococcus (GBS) asymptomatically colonizes the vaginal tract of ∼30% of pregnant women, only a fraction of their offspring develops invasive disease. We and others have postulated that these dimorphic clinical phenotypes are driven by strain variability; however, the bacterial factors that promote these divergent clinical phenotypes remain unclear. It was previously shown that GBS produces membrane vesicles (MVs) that contain active virulence factors capable of inducing adverse pregnancy outcomes. Because the relationship between strain variation and vesicle composition or production is unknown, we sought to quantify MV production and examine the protein composition, using label-free proteomics on MVs produced by diverse clinical GBS strains representing three phylogenetically distinct lineages. We found that MV production varied across strains, with certain strains displaying nearly two-fold increases in production relative to others. Hierarchical clustering and principal component analysis of the proteomes revealed that MV composition is lineage-dependent but independent of clinical phenotype. Multiple proteins that contribute to virulence or immunomodulation, including hyaluronidase, C5a peptidase, and sialidases, were differentially abundant in MVs, and were partially responsible for this divergence. Together, these data indicate that production and composition of GBS MVs vary in a strain-dependent manner, suggesting that MVs have lineage-specific functions relating to virulence. Such differences may contribute to variation in clinical phenotypes observed among individuals infected with GBS strains representing distinct lineages.
Developmental timing ofDrosophila pacheapupae is robust to temperature changes
Authors: Lefèvre Bénédicte M. , Mienanzambi Stecy , Lang Michael 
Published: August 2021

AbstractRearing temperature is correlated with the timing and speed of development in a wide range of poikiloterm animals that do not regulate their body temperature. However, exceptions exist, especially in species that live in environments with high temperature extremes or oscillations.Drosophila pacheais endemic to the Sonoran desert in Mexico, in which temperatures and temperature variations are extreme. We wondered if the developmental timing inD. pacheamay be sensitive to differing rearing temperatures or if it remains constant. We determined the overall timing of theDrosophila pachealife-cycle at different temperatures. The duration of pupal development was similar at 25°C, 29°C and 32°C, although the relative progress differed at particular stages. Thus,D. pacheamay have evolved mechanisms to buffer temperature effects on developmental speed, potentially to ensure proper development and individual’s fitness in desert climate conditions.
A novel multifunctional role for Hsp70 in binding post-translational modifications on client proteins
Authors: Nitika  , Zheng Bo , Ruan Linhao , Kline Jake T. , Sikora Jacek , Torres Mara Texeira , Wang Yuhao , Takakuwa Jade E. , Huguet Romain , Klemm Cinzia , Segarra Verónica A. , Winters Matthew J. , Pryciak Peter M. , Thorpe Peter H. , Tatebayashi Kazuo , Li Rong , Fornelli Luca , Truman Andrew W. 
Published: August 2021

SummaryHsp70 interactions are critical for cellular viability and the response to stress. Previous attempts to characterize Hsp70 interactions have been limited by their transient nature and inability of current technologies to distinguish direct vs bridged interactions. We report the novel use of cross-linking mass spectrometry (XL-MS) to comprehensively characterize the budding yeast Hsp70 protein interactome. Using this approach, we have gained fundamental new insights into Hsp70 function, including definitive evidence of Hsp70 self-association as well as multi-point interaction with its client proteins. In addition to identifying a novel set of direct Hsp70 interactors which can be used to probe chaperone function in cells, we have also identified a suite of PTM-associated Hsp70 interactions. The majority of these PTMs have not been previously reported and appear to be critical in the regulation of client protein function. These data indicate that one of the mechanisms by which PTMs contribute to protein function is by facilitating interaction with chaperones. Taken together, we propose that XL-MS analysis of chaperone complexes may be used as a unique way to identify biologically-important PTMs on client proteins.In vivoconfirmation of Hsp70 dimerizationComprehensive direct interactome of Hsp70Multi-domain interactions between Hsp70 and client proteinsIdentification of novel biologically-important client protein PTMs
COVID-19 and global clothing retailers' responsibility to vulnerable workers: NGO counter-rhetoric
Authors: Ahmad Nglaa , Haque Shamima , Islam Muhammad Azizul 
Published: August 2021

PurposeThis article aims to examine how non-governmental organisations (NGOs)' narratives portray the vulnerability of workers in global clothing supply chains during the COVID-19 crisis.Design/methodology/approachThe research analyses the rhetoric in global clothing retailers' and NGOs' counter-rhetoric during the first seven months of 2020.FindingsDuring this period, retailers employed rhetorical strategies to legitimise irresponsible actions (corporate hegemony prevailed), while NGOs embraced forms of counter-rhetoric trying to delegitimise the retailers' logic, stressing the role of neoliberalism in worsening the situation.Originality/valueThe authors contribute to the literature by providing new insight into the consequences of COVID-19 for retailers' neoliberal practices and the livelihood of workers in global supply chains. Findings of this study extend authors’ knowledge about retailers' COVID-19 measures: These have contributed to the plights of workers working for their supply factories in the global South.
TFP determinants in the manufacturing sector: the case of Ecuadorian firms
Authors: Camino-Mogro Segundo 
Published: August 2021

Purpose
Using a large firm-level data set, this paper examines total factor productivity (TFP) and its determinants in the Ecuadorian manufacturing sector in the period 2007–2018.

Design/methodology/approach
I analyze the role played by traditional TPF determinants, including internal firm characteristics, international trade activities, financial constraints and competition intensity. I contribute to the literature by presenting quantile regression results. Moreover, I analyze industry patterns, distinguishing between industries according to their technological intensity (following the organisation for economic co-operation and development classification).

Findings
My results confirm that firm age is positively related to TFP level but negatively related to TFP growth. I also find that being an exporter and an importer at the same time is associated with higher TFP levels and that this effect is higher than when being only an exporter or an importer. Additionally, l find that credit is positively related to TFP levels. Finally, I find that more competition is positively related to productivity in lower quantiles of output.

Practical implications
The results are the source of tools to propose policy recommendations, which are stated in the present document.

Originality/value
This paper aims to reopen the debate of firm productivity determinants in a developing country such as Ecuador. The authors use a set of covariates less analyzed in this issue.
Mitigating the impact of SARS-CoV-2 on residential facilities for persons with intellectual disability and/or autism spectrum disorder: two experiences from the Italian red zone
Authors: Santambrogio Jacopo , Russo Michela , Terrevazzi Sergio , Peschi Gianluca , Clerici Massimo , Bertelli Marco O. 
Published: August 2021

Purpose
Persons with intellectual disability and/or low-functioning autism spectrum didorder are with high support need (ID/ASD-HSN) are among the people who are most vulnerable to the COVID-19 pandemic. The specific vulnerability and the protective factors for persons with ID/LF-ASD attending residential and rehabilitative facilities have however received little attention. This paper aims to describe how two facilities located in the Italian COVID-19 red zone faced the risks associated with the spread of the pandemic and the results they have achieved so far.

Design/methodology/approach
Interventions to contrast the spread of the pandemic and preserve clients’ health conditions have been systematically monitored and recorded since the very beginning of the pandemic.

Findings
26/138 clients had to undergo clinical screening and laboratory tests for COVID-like symptomatology, but only one resulted affected by COVID-19 and survived. Considering that Lombardy had 89,595 cases and 16,262 deaths (January–May 2020), one COVID-19 case/138 clients is a good result. Temporarily limiting physical contacts with friends/family in favor of reducing the burden of risk and adopting a system of prevention/safety strategies directed for persons with ID/LF-ASD attending and their caregivers have been useful measures.

Research limitations/implications
Structured or semi-structured interviews (using professional caregivers as informant) to confirm behavioral and emotional changes in the clients could not be carried out because of lack of time and resources (which were captured by the management of the pandemic) and could be the next goal for our residential facilities to implement the management of epidemic acute phases in a research-oriented view.

Originality/value
This study is a service evaluation report about facing COVID-19 pandemic. Only few such studies are present in medical literature about ID/ASD.
Exploring consumer loyalty towards brands of safe vegetables in Vietnam
Authors: Ngo Hai Minh , Liu Ran , Taieb Seifeddine Ben , Moritaka Masahiro , Fukuda Susumu 
Published: August 2021

PurposeExpanding the market share of safe food through a modern retail system has faced a lot of difficulties in Vietnam. Thus, a further understanding of consumer behaviour and loyalty towards such food is essential for food retailers. This study aims at exploring segments of consumer loyalty and its influential factors towards safe food brands in the country.Design/methodology/approachBased on a sample of 250 consumers buying safe food in Hanoi city in February 2019, two-step cluster and multinomial logistic regression analyses were applied.FindingsThe results show that four segments of brand loyalty were formed from the interaction between attitudinal and behavioural loyalty as the framework of Dick and Basu (1994), namely, true loyalty, spurious loyalty, latent loyalty and disloyalty. Notably, over 60% of the consumers were in latent loyalty and spurious loyalty, indicating variety-seeking behaviour, multi-brand loyalty or low recognition of the brand. Consumer satisfaction was the most vital motivating consumers to higher loyalty levels. Additionally, brand trust and brand familiarity played significant roles in developing true brand loyalty. An attractive selling store and friendly staff were also important in enhancing brand loyalty.Originality/valueThis study is one of the first to elicit consumer loyalty and identify factors driving the loyalty towards brands of safe food in a developing country like Vietnam.
Politics, government health expenditure and infant mortality: does political party orientation matter?
Authors: Alexiou Constantinos , Trachanas Emmanouil 
Published: August 2021

PurposeMotivated by the scant available evidence, this paper explores the relationship between government political party orientation and infant mortality.Design/methodology/approachA panel quantile methodology is applied to a data set that consists of 15 countries of the G20 group over the period 2000–2018. The authors control for heterogeneous parameters across countries and quantiles and obtain estimates across the different points of the conditional distribution of the dependent variable.FindingsThe findings support the hypothesis that political party orientation has a significant effect on a population health indicator such as infant mortality. The analysis suggests that, to a great extent, left-wing government parties contribute to better health outcomes – when compared to right and centre political parties – both individually as well as interacted with government health expenditure. Moreover, the impact of redistributing policies appears to be of a paramount importance in alleviating infant mortality, while more education and lower unemployment can also contribute to better health outcomes.Originality/valueThe authors explore the relationship between the nature of government political party orientation (i.e. right, centre and left) and infant mortality whilst at the same time gauging the mediating effect of party orientation via government health expenditure on infant mortality. Additional aspects of the impact of other control variables, such as income inequality, unemployment and education on infant mortality are also investigated.
Exploring personal definitions of sustainability and their impact on perceptions of sustainability culture
Authors: Alexander Rob , Jacovidis Jessica , Sturm Deborah 
Published: August 2021

Purpose
The purpose of this paper is to present an exploratory analysis of campus community member (i.e. students, faculty, staff) definitions of sustainability, their perceptions of select elements of sustainability culture and the relationship between the two.

Design/methodology/approach
Researchers implemented a cross-sectional design where participants from two higher education institutions in the USA completed an online survey. The 352 respondents from James Madison University and 349 respondents from Wofford College included students, faculty and staff members. Descriptive statistics were used to examine patterns in the quantitative data, and an inductive theme approach was used to analyze the qualitative data.

Findings
This study provides evidence that sustainability is often viewed from an environmental lens, and personal definitions of sustainability may impact perceptions of campus sustainability culture elements. Generally, the highest rated elements of culture examined (i.e. university actions, signs and symbols and institutional commitments) were all aligned with the environment dimension of sustainability and consistent across sustainability definitions. However, respondents with a more integrative definition of sustainability expected to see elements of culture that aligned with the social dimension of sustainability at a considerably higher rate than the respondents who reported more narrow definitions of sustainability.

Research limitations/implications
Lack of generalizability, low response rates and self-selection bias are some of the limitations of the study.

Practical implications
Personal definitions of sustainability may impact campus community member perceptions of sustainability culture and progress on their campuses. Practitioners may use this study to inform development of more effective strategies for creating and assessing the culture of sustainability that colleges and universities are pursuing.

Originality/value
The empirical analysis of campus community members on two very different campus communities responds to Owens and Legere (2015) who argue for further studies to understand the concept of sustainability at other higher education institutions that are at different stages of pursuing sustainability. This paper links research about sustainability definitions to the emergent research on campus sustainability culture, filling a gap between these two areas.
Past, present and future of luxury brands: a review and bibliometric analysis
Authors: Husain Rehan , Samad Taab Ahmad , Qamar Yusra 
Published: August 2021

PurposeThis study aims to identify the present research trends and streamline future research possibilities in luxury brands by a systematic review of the existing literature.Design/methodology/approachA portfolio of 552 articles published between 1996 and 2020 in the luxury brands domain is collected from the Scopus database and analyzed using an integrated approach comprising bibliometric and content analyses.FindingsA comprehensive review of the available literature was done by identifying emerging topics, keywords and research themes. The study's findings indicate that the luxury brand is an exponentially growing theme; seven representative research clusters are identified and analyzed.Originality/valueThis study enriches the literature of luxury brand by presenting a holistic view of the academic literature using an integrated research methodology comprising bibliometric and content analysis techniques.