Development of impedance spectroscopy based in-situ, self-calibrating, on-board wireless sensor with inbuilt metamaterial inspired small antenna for constituent detection in multi-phase mixtures like soil

Real time and accurate measurement of sub-surface soil moisture and nutrients is critical for agricultural and environmental studies. This work presents a novel on-board solution for a robust, accurate and self-calibrating soil moisture and nutrient sensor with inbuilt wireless transmission and reception capability that makes it ideally suited to act as a node in a network spread over a large area. The sensor works on the principle of soil impedance measurement by comparing the amplitude and phase of signals incident on and reflected from the soil in proximity of the sensor. The permittivity of the soil dielectric mixture which is calculated from these impedance measurements is used as input parameter to the dielectric mixing models which are used to estimate the ionic concentration in soil. The inbuilt wireless transceiver system is connected to a specially designed metamaterial inspired small antenna in order to reduce the sensor size while keeping the path losses to a minimum by using a low frequency. This composite right-left handed (CRLH) antenna for wireless transmission at 433 MHz doubles up as an underground, sensing element (external capacitor) and integrates with the on-board sensor for soil moisture and nutrient determination. The input impedance of the CRLH sensor, surrounded by the soil containing moisture and nutrient and other ions, is measured at multiple frequencies. It is shown that the change in moisture and ioinic-concentration can be successfully detected using the sensor. The inbuilt self-calibrating mechanism makes the sensor reliable at different environmental conditions and also useful for remote, underground and hand-held applications. A multi-power mode transceiver system has been designed to support the implementation of an energy efficient medium-access-control

Zebrafish as a Model for Drug Screening in Genetic Kidney Diseases

Genetic disorders account for a wide range of renal diseases emerging during childhood and adolescence. Due to the utilization of modern biochemical and biomedical techniques, the number of identified disease-associated genes is increasing rapidly. Modeling of congenital human disease in animals is key to our understanding of the biological mechanism underlying pathological processes and thus developing novel potential treatment options. The zebrafish (Danio rerio) has been established as a versatile small vertebrate organism that is widely used for studying human inherited diseases. Genetic accessibility in combination with elegant experimental methods in zebrafish permit modeling of human genetic diseases and dissecting the perturbation of underlying cellular networks and physiological processes. Beyond its utility for genetic analysis and pathophysiological and mechanistic studies, zebrafish embryos, and larvae are amenable for phenotypic screening approaches employing high-content and high-throughput experiments using automated microscopy. This includes large-scale chemical screening experiments using genetic models for searching for disease-modulating compounds. Phenotype-based approaches of drug discovery have been successfully performed in diverse zebrafish-based screening applications with various phenotypic readouts. As a result, these can lead to the identification of candidate substances that are further examined in preclinical and clinical trials. In this review, we discuss zebrafish models for inherited kidney disease as well as requirements and considerations for the technical realization of drug screening experiments in zebrafish

Kinetic and sequence-structure-function analysis of known LinA variants with different hexachlorocyclohexane isomers

BACKGROUND Here we report specific activities of all seven naturally occurring LinA variants towards three different isomers, α, γ and δ, of a priority persistent pollutant, hexachlorocyclohexane (HCH). Sequence-structure-function differences contributing to the differences in their stereospecificity for α-, γ-, and δ-HCH and enantiospecificity for (+)- and (-)-α -HCH are also discussed. METHODOLOGY/PRINCIPAL FINDINGS Enzyme kinetic studies were performed with purified LinA variants. Models of LinA2(B90A) A110T, A111C, A110T/A111C and LinA1(B90A) were constructed using the FoldX computer algorithm. Turnover rates (min(-1)) showed that the LinAs exhibited differential substrate affinity amongst the four HCH isomers tested. α-HCH was found to be the most preferred substrate by all LinA's, followed by the γ and then δ isomer. CONCLUSIONS/SIGNIFICANCE The kinetic observations suggest that LinA-γ1-7 is the best variant for developing an enzyme-based bioremediation technology for HCH. The majority of the sequence variation in the various linA genes that have been isolated is not neutral, but alters the enantio- and stereoselectivity of the encoded proteins.This work was supported by the Indo-Australian Biotechnology Fund from the Department of Education Science and Technology (DEST), Australia and the Department of Biotechnology (DBT), India

Kinetic and Sequence-Structure-Function Analysis of Known LinA Variants with Different Hexachlorocyclohexane Isomers

BACKGROUND: Here we report specific activities of all seven naturally occurring LinA variants towards three different isomers, α, γ and δ, of a priority persistent pollutant, hexachlorocyclohexane (HCH). Sequence-structure-function differences contributing to the differences in their stereospecificity for α-, γ-, and δ-HCH and enantiospecificity for (+)- and (-)-α -HCH are also discussed. METHODOLOGY/PRINCIPAL FINDINGS: Enzyme kinetic studies were performed with purified LinA variants. Models of LinA2(B90A) A110T, A111C, A110T/A111C and LinA1(B90A) were constructed using the FoldX computer algorithm. Turnover rates (min(-1)) showed that the LinAs exhibited differential substrate affinity amongst the four HCH isomers tested. α-HCH was found to be the most preferred substrate by all LinA's, followed by the γ and then δ isomer. CONCLUSIONS/SIGNIFICANCE: The kinetic observations suggest that LinA-γ1-7 is the best variant for developing an enzyme-based bioremediation technology for HCH. The majority of the sequence variation in the various linA genes that have been isolated is not neutral, but alters the enantio- and stereoselectivity of the encoded proteins

Bacterial community structure of a pesticide-contaminated site and assessment of changes induced in community structure during bioremediation

The introduction of culture-independent molecular screening techniques, especially based on 16S rRNA gene sequences, has allowed microbiologists to examine a facet of microbial diversity not necessarily reflected by the results of culturing studies. The bacterial community structure was studied for a pesticide-contaminated site that was subsequently remediated using an efficient degradative strain Arthrobacter protophormiae RKJ100. The efficiency of the bioremediation process was assessed by monitoring the depletion of the pollutant, and the effect of addition of an exogenous strain on the existing soil community structure was determined using molecular techniques. The 16S rRNA gene pool amplified from the soil metagenome was cloned and restriction fragment length polymorphism studies revealed 46 different phylotypes on the basis of similar banding patterns. Sequencing of representative clones of each phylotype showed that the community structure of the pesticide-contaminated soil was mainly constituted by Proteobacteria and Actinomycetes. Terminal restriction fragment length polymorphism analysis showed only nonsignificant changes in community structure during the process of bioremediation. Immobilized cells of strain RKJ100 enhanced pollutant degradation but seemed to have no detectable effects on the existing bacterial community structur

Comparative meta-analysis of antimicrobial resistance from different food sources along with one health approach in the Egypt and UK

Background: Antimicrobial resistance (AMR) is a critical global issue that poses significant threats to human health, animal welfare, and the environment. With the increasing emergence of resistant microorganisms, the effectiveness of current antimicrobial medicines against common infections is diminishing. This study aims to conduct a competitive meta-analysis of surveillance data on resistant microorganisms and their antimicrobial resistance patterns in two countries, Egypt and the United Kingdom (UK). Methods: Data for this study were obtained from published reports spanning the period from 2013 to 2022. In Egypt and the UK, a total of 9,751 and 10,602 food samples were analyzed, respectively. Among these samples, 3,205 (32.87%) in Egypt and 4,447 (41.94%) in the UK were found to contain AMR bacteria. Results: In Egypt, the predominant resistance was observed against β-lactam and aminoglycosides, while in the United Kingdom, most isolates exhibited resistance to tetracycline and β-lactam. The findings from the analysis underscore the increasing prevalence of AMR in certain microorganisms, raising concerns about the development of multidrug resistance. Conclusion: This meta-analysis sheds light on the escalating AMR problem associated with certain microorganisms that pose a higher risk of multidrug resistance development. The significance of implementing One Health AMR surveillance is emphasized to bridge knowledge gaps and facilitate accurate AMR risk assessments, ensuring consumer safety. Urgent actions are needed on a global scale to combat AMR and preserve the effectiveness of antimicrobial treatments for the well-being of all living beings

Identification of candidate odorant degrading gene/enzyme systems in the antennal transcriptome of Drosophila melanogaster

AbstractThe metabolism of volatile signal molecules by odorant degrading enzymes (ODEs) is crucial to the ongoing sensitivity and specificity of chemoreception in various insects, and a few specific esterases, cytochrome P450s, glutathione S-transferases (GSTs) and UDP-glycosyltransferases (UGTs) have previously been implicated in this process. Significant progress has been made in characterizing ODEs in Lepidoptera but very little is known about them in Diptera, including in Drosophila melanogaster, a major insect model. We have therefore carried out a transcriptomic analysis of the antennae of D. melanogaster in order to identify candidate ODEs. Virgin male and female and mated female antennal transcriptomes were determined by RNAseq. As with the Lepidoptera, we found that many esterases, cytochrome P450 enzymes, GSTs and UGTs are expressed in D. melanogaster antennae. As olfactory genes generally show selective expression in the antennae, a comparison to previously published transcriptomes for other tissues has been performed, showing preferential expression in the antennae for one esterase, JHEdup, one cytochrome P450, CYP308a1, and one GST, GSTE4. These largely uncharacterized enzymes are now prime candidates for ODE functions. JHEdup was expressed heterologously and found to have high catalytic activity against a chemically diverse group of known ester odorants for this species. This is a finding consistent with an ODE although it might suggest a general role in clearing several odorants rather than a specific role in clearing a particular odorant. Our findings do not preclude the possibility of odorant degrading functions for other antennally expressed esterases, P450s, GSTs and UGTs but, if so, they suggest that these enzymes also have additional functions in other tissues