scholarly journals Metabolic Current Production by an Oral Biofilm Pathogen Corynebacterium matruchotii

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3141
Author(s):  
Divya Naradasu ◽  
Waheed Miran ◽  
Akihiro Okamoto
Keyword(s):  
Metabolic Activity ◽  
High Resolution Mass Spectrometry ◽  
Electrode System ◽  
Human Pathogens ◽  
Oral Biofilm ◽  
Hydrogen Electrode ◽  
Production Capability ◽  
Current Production ◽  
The Impact ◽  
Microbial Metabolic Activity

The development of a simple and direct assay for quantifying microbial metabolic activity is important for identifying antibiotic drugs. Current production capabilities of environmental bacteria via the process called extracellular electron transport (EET) from the cell interior to the exterior is well investigated in mineral-reducing bacteria and have been used for various energy and environmental applications. Recently, the capability of human pathogens for producing current has been identified in different human niches, which was suggested to be applicable for drug assessment, because the current production of a few strains correlated with metabolic activity. Herein, we report another strain, a highly abundant pathogen in human oral polymicrobial biofilm, Corynebacterium matruchotii, to have the current production capability associated with its metabolic activity. It showed the current production of 50 nA/cm2 at OD600 of 0.1 with the working electrode poised at +0.4 V vs. a standard hydrogen electrode in a three-electrode system. The addition of antibiotics that suppress the microbial metabolic activity showed a significant current decrease (>90%), establishing that current production reflected the cellular activity in this pathogen. Further, the metabolic fixation of atomically labeled 13C (31.68% ± 2.26%) and 15N (19.69% ± 1.41%) confirmed by high-resolution mass spectrometry indicated that C. matruchotii cells were metabolically active on the electrode surface. The identified electrochemical activity of C. matruchotii shows that this can be a simple and effective test for evaluating the impact of antibacterial compounds, and such a method might be applicable to the polymicrobial oral biofilm on electrode surfaces, given four other oral pathogens have already been shown the current production capability.

The contribution of instream wood to streambed organic matter controls on microbial metabolic activity

2021 ◽  
Author(s):  
Ben Howard ◽  
Sami Ullah ◽  
Nick Kettridge ◽  
Ian Baker ◽  
Stefan Krause
Keyword(s):  
Organic Matter ◽  
Metabolic Activity ◽  
Ghg Emissions ◽  
Catchment Management ◽  
Turnover Rates ◽  
Nutrient Turnover ◽  
Instream Wood ◽  
The Impact ◽  
Microbial Metabolic Activity

<p>Microbial metabolic activity (MMA) in streambeds drives greenhouse gas (GHG) production and nutrient turnover. Previous research has identified that the quantity and quality of organic matter (OM) are important controls on MMA. Instream wood may make a significant contribution to the total OM content of the streambed, especially in forested streams, but it has typically been ignored or explicitly omitted in previous research. By means of an incubation experiment, we investigate the impact of streambed wood on MMA, GHG production and nutrient turnover rates. By using three geologies (sandstone, chalk and limestone) and allowing temperatures to fluctuate with environmental conditions, we observe these impacts under a range of typical scenarios. These results could have implications for estimates of GHG emissions from streams and inform catchment management, for example the impacts of direct installation of instream wood in river restoration or the indirect input as a result of riparian planting.</p>

scholarly journals Insignificant Impact of Chemotactic Responses of Pseudomonas aeruginosa on the Bacterial Attachment to Organic Pre-Conditioned RO Membranes

Membranes ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 162
Author(s):  
Lan Hee Kim ◽  
Johannes S. Vrouwenvelder
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Metabolic Activity ◽  
Membrane Surface ◽  
Feed Solution ◽  
Physicochemical Characteristics ◽  
Bacterial Attachment ◽  
Organic Substances ◽  
Pseudomonas Aeruginosa Pao1 ◽  
The Impact ◽  
Microbial Metabolic Activity

We investigated the impact of conditioning compositions on the way bacteria move and adhere to reverse osmosis (RO) membranes that have been pre-conditioned by organic compounds. We used humic acid (HA), bovine serum albumin (BSA), and sodium alginate (SA) to simulate conditioning layers on the RO membranes. First, we investigated the chemotactic responses of Pseudomonas aeruginosa PAO1 to the organic substances and the impact of changes in physicochemical characteristics of pre-conditioned membranes on bacterial attachment. Second, we observed bacterial attachment under the presence or absence of nutrients or microbial metabolic activity. Results showed that there was no relationship between the chemotactic response of P. aeruginosa PAO1 and the organic substances, and the changes in hydrophobicity, surface free energy, and surface charge resulting from changing the composition of the conditioning layer did not seem to affect bacterial attachment, whereas changing the roughness of the conditioned membrane exponentially did (exponential correlation coefficient, R2 = 0.85). We found that the initial bacterial attachment on the membrane surface is influenced by (i) the nutrients in the feed solution and (ii) the microbial metabolic activity, whereas the chemotaxis response has a negligible impact. This study would help to establish a suitable strategy to manage bacterial attachment.

scholarly journals Estimating the Impact of Decoupled Payments on Farm Production in Northern Ireland: An Instrumental Variable Fixed Effect Approach

2020 ◽  
Vol 12 (8) ◽  
pp. 3222
Author(s):  
Kehinde Oluseyi Olagunju ◽  
Myles Patton ◽  
Siyi Feng
Keyword(s):  
Northern Ireland ◽  
Agricultural Policy ◽  
Instrumental Variable ◽  
Fixed Effect Model ◽  
Livestock Production ◽  
Fixed Effect ◽  
Agricultural Subsidies ◽  
Decoupled Payments ◽  
Current Production ◽  
The Impact

The production stimulating impact of agricultural subsidies has been a well-debated topic in agricultural policy analysis for some decades. In light of the EU reform of the Common Agricultural Policy (CAP) in year 2005 in which agricultural subsidies were decoupled from current production decisions and the modification to this payment in 2015, this study investigates the impact of decoupled payments under these two reforms on livestock production in Northern Ireland. The study uses a farm-level panel dataset covering 2008–2016 period and employs an instrumental variable fixed effect model to control for relevant sources of endogeneity bias. According to the empirical results, the production impacts of decoupled payments were positive and significant but with differential impacts across livestock production sectors, suggesting that decoupled payments still maintain a significant effect on agricultural production and provide an indication of the supply response to changes in decoupled payments.

scholarly journals The impact of bZIP Atf1ortholog global regulators in fungi

2021 ◽  
Author(s):  
Éva Leiter ◽  
Tamás Emri ◽  
Klaudia Pákozdi ◽  
László Hornok ◽  
István Pócsi
Keyword(s):  
Transcription Factors ◽  
Stress Response ◽  
Secondary Metabolite ◽  
Plant Pathogens ◽  
Leucine Zipper ◽  
Secondary Metabolite Production ◽  
Special Focus ◽  
Human Pathogens ◽  
Metabolite Production ◽  
The Impact

Abstract Regulation of signal transduction pathways is crucial for the maintenance of cellular homeostasis and organismal development in fungi. Transcription factors are key elements of this regulatory network. The basic-region leucine zipper (bZIP) domain of the bZIP-type transcription factors is responsible for DNA binding while their leucine zipper structural motifs are suitable for dimerization with each other facilitiating the formation of homodimeric or heterodimeric bZIP proteins. This review highlights recent knowledge on the function of fungal orthologs of the Schizosaccharomyces pombe Atf1, Aspergillus nidulans AtfA, and Fusarium verticillioides FvAtfA, bZIP-type transcription factors with a special focus on pathogenic species. We demonstrate that fungal Atf1-AtfA-FvAtfA orthologs play an important role in vegetative growth, sexual and asexual development, stress response, secondary metabolite production, and virulence both in human pathogens, including Aspergillus fumigatus, Mucor circinelloides, Penicillium marneffei, and Cryptococcus neoformans and plant pathogens, like Fusarium ssp., Magnaporthe oryzae, Claviceps purpurea, Botrytis cinerea, and Verticillium dahliae. Key points • Atf1 orthologs play crucial role in the growth and development of fungi. • Atf1 orthologs orchestrate environmental stress response of fungi. • Secondary metabolite production and virulence are coordinated by Atf1 orthologs.

scholarly journals The Potential Role of Nonhuman Primate Models to Better Comprehend Early Life Immunity and Maternal Antibody Transfer

Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 306
Author(s):  
Julie Sartoretti ◽  
Christiane S. Eberhardt
Keyword(s):  
Nonhuman Primate ◽  
Early Life ◽  
Cost Effective ◽  
Maternal Antibody ◽  
Maternal Antibodies ◽  
Immunological Methods ◽  
Human Pathogens ◽  
Childhood Immunization ◽  
Primate Model ◽  
The Impact

Early life immunity is a complex field of research and there are still gaps in knowledge regarding the detailed mechanism of maternal antibody transfer, the impact of maternal antibodies on infant vaccine responses and the ontogeny of human early life immunity. A comprehensive understanding is necessary to identify requirements for early life vaccines and to improve early childhood immunization. New immunological methods have facilitated performing research in the youngest, however, some questions can only be addressed in animal models. To date, mostly murine models are used to study neonatal and infant immunity since they are well-described, easy to use and cost effective. Given their limitations especially in the transfer biology of maternal antibodies and the lack of infectivity of numerous human pathogens, this opinion piece discusses the potential and prerequisites of the nonhuman primate model in studying early life immunity and maternal antibody transfer.

Buyer-assisted lean intervention in supplier firms: a supplier development approach

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Imranul Hoque
Keyword(s):  
Financial Incentives ◽  
Large Scale ◽  
Qualitative Data ◽  
Research Approach ◽  
Capability Development ◽  
Content Type ◽  
Production Capability ◽  
Lean Tools ◽  
The Right ◽  
The Impact

PurposeThis study aims to investigate how buyer-assisted lean intervention in garment supplier factories affects garment suppliers' productivity and production capability development.Design/methodology/approachEmploying a qualitative research approach and a lean intervention design, a multiple case study method was adopted for this study. Quantitative data on productivity performance and qualitative data on production capability development were collected from a Danish buyer and their four corresponding garment suppliers. Collected data were analysed using standard lean measurement tools and qualitative data analysis techniques.FindingsThis study demonstrates that buyer-assisted lean intervention is a useful strategy for garment suppliers to enhance their productivity and production capability. However, suppliers need to select the right lean tools, ensure seriousness and commitment to lean initiatives, substantial involvement of top management and workers, arrange formal and informal training, provide performance-based financial/non-financial incentives and nurture a learning culture to facilitate suppliers' production capability development.Research limitations/implicationsThis study implemented few lean tools in a single sewing line in four supplier factories for a short intervention duration. Thus, there is a scope for future studies to investigate the impact of the lean intervention on a large scale.Practical implicationsThe findings of this study might bring new insights to the management of buyer and supplier firms concerning how buyers could involve in suppliers' lean intervention initiatives and what suppliers need to ensure to develop production capability.Originality/valueFor the first time, this study engaged a buyer in suppliers' lean intervention initiatives to improve productivity and production capability in the garment industry of a developing country.

scholarly journals Earthworm communities and microbial metabolic activity and diversity under conventional, feed and biogas cropping systems as affected by tillage practices

2022 ◽  
Vol 169 ◽  
pp. 104232
Author(s):  
Julia Denier ◽  
Michel-Pierre Faucon ◽  
Anne-Maïmiti Dulaurent ◽  
Julien Guidet ◽  
Léa Kervroëdan ◽  
...  
Keyword(s):  
Metabolic Activity ◽  
Cropping Systems ◽  
Tillage Practices ◽  
Microbial Metabolic Activity

scholarly journals Characterisation of Bt maize IE09S034 in decomposition and response of soil bacterial communities

2021 ◽  
Author(s):  
Xiaoli Zhou ◽  
Jingang Liang ◽  
Ying Luan ◽  
Xinyuan Song ◽  
Zhengguang Zhang
Keyword(s):  
Metabolic Activity ◽  
Bacterial Communities ◽  
Bt Maize ◽  
Gm Crop ◽  
Soil Bacterial Communities ◽  
Significant Difference ◽  
Maize Residues ◽  
Soil Bacterial ◽  
June July ◽  
The Impact

Returning straw to the soil is an effective way to improve the soil quality. As genetically modified (GM) crops experience expanded growing scales, returning straw to the soil could also be necessary. However, the impact of GM crop straws on soil safety remains unclear. The environment (including soil types, humidity and temperature) can result in a significant difference in the diversity of soil bacterial communities. Here, we compared the impacts of the straw from Bt maize IE09S034 (IE) and near-isogenic non-Bt maize Zong31 (CK) on soil bacterial community and microbial metabolic activity in three different environments. Sampling was carried out following 6–10 months of decomposition (May, June, July, and August) in three localities in Chinese cities (Changchun, Jinan, and Beijing). Our results showed that Bt maize residues posed no direct impact on soil bacterial communities in contrast to the environment and decomposed time. The microbial functional diversity and metabolic activity showed no significant difference between IE and CK. The results could be a reference for further assessing the effect of Bt maize residues on the soil that promotes the commercialisation of Bt maize IE09S034.

scholarly journals Predictive value of suvmax changes between two sequential post-therapeutic FDG-pet in head and neck squamous cell carcinomas

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Thomas M. Stadler ◽  
Martin W. Hüllner ◽  
Martina A. Broglie ◽  
Grégoire B. Morand
Keyword(s):  
Head And Neck ◽  
Squamous Cell ◽  
Metabolic Activity ◽  
Fdg Pet ◽  
Tumor Recurrence ◽  
Standardized Uptake Value ◽  
University Hospital ◽  
Position Emission Tomography ◽  
The Impact

Abstract 18-flurodesoxyglucose position emission tomography (FDG-PET) with computed tomography (CT) or magnetic resonance imaging (MRI) is a broadly accepted tool for pretherapeutic staging and post-therapeutic assessment of response. The prognostic value of sequential post-therapeutic FDG-PETs and the impact of change in metabolic activity has been scarcely reported so far. We hypothesized that an increase in metabolic activity (as measured by maximum standardized uptake value, SUVmax) would be predictive for recurrence. We retrospectively assessed all oral, oropharyngeal, laryngeal, and hypopharyngeal squamous cell carcinoma patients treated at the Department of Otorhinolaryngology—Head and Neck Surgery, University Hospital Zurich between April 1st, 2010 and September 30th, 2018 (N = 337). After a negative post-treatment FDG-PET at 3 months, we measured the SUVmax of the local tumor area and the regional lymph nodes on follow-up FDG-PET at 9 months. We then correlated SUVmax difference between 9 and 3 months with tumor recurrence using Kaplan Meier analysis. During follow-up, 68 patients (20.2%) had local recurrence and 53 had regional recurrence (15.7%) at a median time of 9.0 (IQR 4.25–14) and 7.0 (IQR 5.25–23) months, respectively. An increase in local and/or regional SUVmax from the 3 months to the 9 months post-therapeutic FDG-PET resulted in a poorer recurrence-free survival (Log rank, P = 0.001, for both). An increase in local SUVmax between 3 and 9 months was associated with a hazard ratio of 4.17 for recurrence (95%CI 1.89–9.2, P = 0.0003). In conclusion, an increase in metabolic activity/SUVmax between two post-therapeutic FDG-PETs requires a histological examination as it is associated with tumor recurrence.

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