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Rice straw decomposition is an attractive solution to open-field burning but the traditional method has slow kinetics and takes 60-90 days to obtain mature compost. In this study, we propose to boost up the decomposition process by addition of a novel microbial consortium rich in lignocellulolytic microbes. C: N ratio of the compost reached 11.69% and degradation efficiency of cellulose and hemicellulose was found to be 64 and 87% respectively within 25 days. Lignocellulolytic activity of the microbial consortium was confirmed by plate and activity assay. These parameters clearly indicated that a mature compost was obtained in 25 days. The 16S rRNA gene amplicon sequencing and functional analysis of predicted genes indicated amino acid and carbohydrate metabolism as the major metabolic pathway during composting. The tertiary level of functional analysis revealed the major metabolic pathways in the bacterial communities as pentose phosphate pathway, glycolysis and tricarboxylic acid cycle.

There is compelling evidence implicating intestinal permeability in the pathogenesis of nonalcoholic steatohepatitis (NASH), but the underlying mechanisms remain poorly understood. Here we examined the role of bile acids (BA) in western diet (WD)-induced loss of colonic epithelial barrier (CEB) function in mice with a genetic impairment in intestinal epithelial barrier function, junctional adhesion molecule A knockout mice, F11r(−/−). WD-fed knockout mice developed severe NASH, which was associated with increased BA concentration in the cecum and loss of CEB function. Analysis of cecal BA composition revealed selective increases in primary unconjugated BAs in the WD-fed mice, which correlated with increased abundance of microbial taxa linked to BA metabolism. In vitro permeability assays revealed that chenodeoxycholic acid (CDCA), which was elevated in the cecum of WD-fed mice, increased paracellular permeability, while the BA-binding resin sevelamer hydrochloride protected against CDCA-induced loss of barrier function. Sequestration of intestinal BAs by in vivo delivery of sevelamer to WD-fed knockout mice attenuated colonic mucosal inflammation and improved CEB. Sevelamer also reduced hepatic inflammation and fibrosis, and improved metabolic derangements associated with NASH. Collectively, these findings highlight a hitherto unappreciated role for BAs in WD-induced impairment of the intestinal epithelial barrier in NASH.

The analysis of hexavalent chromium (Cr (VI)) is an important water quality monitoring for public health safe consumption. Many high-end instruments were accessible to detect total Cr precisely at parts per trillion. Because of high upkeep of instruments, important to recognise on field examination and adjusting to low-volume (green chemistry) was quite challenging. The potential methods of detecting Cr in on-spot field examination were colorimetry. Numerous scientists were carried out by lab or compact spectrophotometer using 1,5-diphenylcarbazide and ability to produce magenta at 540 nm absorbance. The detection limit was achieved as per the WHO regulation levels. Still the requirement of standardisation in the field analysis was not completely suitable for low-volume due to use of standard chemicals. So in our study, the regular method was evaluated with the colour science approach by uniform (Lab, HLab and XYZ) and non-uniform models (RGB) with spectrophotometer and different cameras (mobile and digital still) using its flash light. The study showed Cr (VI) analysis by mobile camera was able to detect at 20 ng/mL. This was far better than recent reported studies with microfluidic and nanotechnology. The analytical relation with ICP-MS and mobile for Cr (VI) was found to be 0.60 (RSE-6.2%) to 0.72 (RSE-6.72%) with adjusted r2 value > 0.98. We have found to be in good agreement of ~70% with 98% confidence level of uniform models than non-uniform. The use of one-time colour standard references of uniform models might be helpful through naked eye judgment and ability to detect at 100 ng/mL based on individual perceptions in field analysis. This will improve in determining the sample collection, site evaluation for remediation and involvement of public in the water monitoring programmes. Further studies have to be conducted in tuning models to detect as precisely like high-end instruments using various NIST SRM standards.

The Internet is a massive collection of information that makes it extremely difficult to search and retrieve the required and valuable information. So, Search engine became an important tool for searching various data from the web. The primary evaluation of search engine is effectiveness and efficiency. While searching for information through search engines, always users retrieve redundant and irrelevant information. This replicated and uninteresting information affects both the effectiveness and efficiency of search engine by wasting users’ time by browsing the uninterested documents and its accessing time. Web content outlier mining plays a significant role in identifying and removing these redundant document (outliers) which is an important issue among the information retrieval and web mining research communities since most of the people rely on search engines to get the required information. Most existing algorithms for web content outlier mining focuses attention on applying weightage only to the common terms in the documents whereas in this research work, a mathematical approach based on term frequency ranking to identify the duplicates, and uses the domain dictionary to check for relevant document has been carried out to improve the effectiveness and efficiency of the search engine.

This study evaluated the effect of bioaugmentation of a newly enriched electroactive bacterial community DC5 on the performance of a pilot scale sequential two-step Horizontal Sub-surface flow Constructed Wetland-Microbial Fuel Cell (HSCW-MFC) system treating textile dye wastewater. The system consisted of CW-MFC-1 planted with Fimbristylis ferruginea and CW-MFC-2 planted with consortium of Fimbristylis ferruginea and Elymus repens plant species. Before bioaugmentation, HSCW-MFC system showed 62 ± 2% Chemical Oxygen Demand (COD) and 90 ± 1.5% American Dye Manufacturer's Institute (ADMI) removal and 177.3 mW/m2 maximum power density (CW-MFC-1). After bioaugmentation of DC5 into the HSCW-MFC, COD and ADMI removal was enhanced to 74.10 ± 1.75% and 97.32 ± 1.90% with maximum power density of 197.94 mW/m2 (CW-MFC-1). The genera Exiguobacterium, Desulfovibrio and Macellibacteroides of DC5 were significantly enriched at the electrodes of HSCW-MFC after bioaugmentation. These results demonstrate that the performance of the CW-MFC treating textile dye wastewater can be improved by bioaugmentation of electroactive bacterial community.

Rivers are the vital support system providing sustainable development and agricultural production to our highly industrialized world. However, extreme anthropogenic inputs have disturbed the natural ecological balance, structures and functions of riverine matrices. The origins, fate and various health hazards of the riverine contaminants are outlined in this chapter. To mitigate the river pollution and restoring its healthy status, effective restoration strategies are required to be adopted, this chapter reviews the application of eco-engineered systems for remediation of the polluted rivers. Different laboratory scale and on-site treatment technologies for river bioremediation are reviewed in this chapter for instance, constructed wetlands, floating islands, bioracks, ecotanks, biofilters, microbial nano-bubble systems, periphyton based bioremediation systems, as well as hybrid integrated treatment systems. The application of combined bioremediation technologies and engineering approaches are discussed for removal of various river pollutants. Suggestions have been made on future research for developing pragmatic approaches in the remediation of polluted riverine ecosystems.

Background & Aims The heterodimeric integrin receptor α4β7 regulates CD4 T cell recruitment to inflamed tissues, but its role in the pathogenesis of non-alcoholic steatohepatitis (NASH) is unknown. Herein, we examined the role of α4β7-mediated recruitment of CD4 T cells to the intestine and liver in NASH. Methods Male littermate F11r+/+ (control) and junctional adhesion molecule A knockout F11r−/− mice were fed a normal diet or a western diet (WD) for 8 weeks. Liver and intestinal tissues were analyzed by histology, quantitative reverse transcription PCR (qRT-PCR), 16s rRNA sequencing and flow cytometry. Colonic mucosa-associated microbiota were analyzed using 16s rRNA sequencing. Liver biopsies from patients with NASH were analyzed by confocal imaging and qRT-PCR. Results WD-fed knockout mice developed NASH and had increased hepatic and intestinal α4β7+ CD4 T cells relative to control mice who developed mild hepatic steatosis. The increase in α4β7+ CD4 T cells was associated with markedly higher expression of the α4β7 ligand mucosal addressin cell adhesion molecule 1 (MAdCAM-1) in the colonic mucosa and livers of WD-fed knockout mice. Elevated MAdCAM-1 expression correlated with increased mucosa-associated Proteobacteria in the WD-fed knockout mice. Antibiotics reduced MAdCAM-1 expression indicating that the diet-altered microbiota promoted colonic and hepatic MAdCAM-1 expression. α4β7 blockade in WD-fed knockout mice significantly decreased α4β7+ CD4 T cell recruitment to the intestine and liver, attenuated hepatic inflammation and fibrosis, and improved metabolic indices. MAdCAM-1 blockade also reduced hepatic inflammation and fibrosis in WD-fed knockout mice. Hepatic MAdCAM-1 expression was elevated in patients with NASH and correlated with higher expression of α4 and β7 integrins. Conclusions These findings establish α4β7/MAdCAM-1 as a critical axis regulating NASH development through colonic and hepatic CD4 T cell recruitment. Lay summary Non-alcoholic steatohepatitis (NASH) is an advanced and progressive form of non-alcoholic fatty liver disease (NAFLD), and despite its growing incidence no therapies currently exist to halt NAFLD progression. Herein, we show that blocking integrin receptor α4β7-mediated recruitment of CD4 T cells to the intestine and liver not only attenuates hepatic inflammation and fibrosis, but also improves metabolic derangements associated with NASH. These findings provide evidence for the potential therapeutic application of α4β7 antibody in the treatment of human NASH.

Assembly of bacterial communities under xenobiotic stress, such as in the presence of various PAHs and their metabolic activities in form of consortia, are less studied. Eight bacterial consortia were developed from PAHs-contaminated sediments in minimal media, using various combinations of naphthalene, phenanthrene, fluoranthene and pyrene. Among eight, competency of consortium ACDMRT-8 was notable, it showed 88.5%, 85.8%, 58.0% and 60.3% degradation of naphthalene, phenanthrene, fluoranthene and pyrene (concentration of total-PAHs 800 ppm, each PAH 200 ppm) within 9 d at room temperature, respectively. After 40 enrichment cycles, bacterial communities were characterized using high-throughput 16S rRNA gene amplicon sequencing of all eight consortia. Though bacterial communities in all consortia were pre-dominated by Proteobacteria, individual diversity varied depending upon enrichment conditions and combinations of PAHs provided. Pseudomonas sp. were abundant in four consortia, which favored all-four PAHs degradation. Bordetella, Chelatococcus and Azoarcus were abundantly found in other consortia with changes in temperature and PAHs. The radical changes in bacterial community at genus level were well reflected in beta-diversity analysis, where four consortia were clustered together, while another group contained three consortia and single consortium remained separated from other two clusters. Dissimilarity analysis using SIMPER suggested that Pseudomonas, Azoarcus, Bordetella, Chelatococcus and Chelativorans formed top 5 abundant genera within eight consortia enriched for PAH biodegradation. Molecular ecological network amongst dominant 17 genera from eight consortia was constructed. The functional competence in form of hydrocarbon degrading genes and pathways were predicted using PICRUSt2 tool and has indicated abundance of ortho-cleavage over meta-cleavage pathways.

The early excitement of industrialization during the twentieth century and unprecedented population rise have now compelled us to think about developing environmental remediation strategies on a priority basis to save the basic essential components of life. Understanding the impact of dyes and dye intermediates which have been the major component of industrial pollutants in the environment is the prime need, to reclaim the pristine environment. Physical and chemical environmental cleanup technologies developed for dye and textile effluents are proven to be expensive and energy consuming, often generate toxic by-products, and more importantly are faced with limited success in a narrower scope. Consequently, the need for an alternate approach has led to the development of self-sustainable, greener biological methods (i.e., bioremediation). It offers a great advantage of astonishing catabolic diversity of the innate microbial population inhabiting the polluted environment. Factors like geological aspects, climate, soil and water characteristics, waste and disposal facilities, etc. play a vital role in the success of different technologies (including bioremediation). Besides chemical structure, degree of recalcitrance, toxicity, and bioavailability of dye molecules are considered significant parameters for their treatments. In this review, an attempt has been made to understand the complexities and constraints of existing technologies and few optimistic scenarios to improve and develop new methodologies for treatment of industrial effluents from dye and textile industries.

The conventional methods for industrial wastewater treatments are now facing challenges to cope up with the emergence of new pollutants, a growing population, rapid industrialization, and most importantly shrinking freshwater resources. Moreover, in many countries the aging of infrastructure is adding to the problem. Therefore a need of the upcoming decade is to develop the advanced treatment technologies for the effective removal of potentially toxic compounds which could not be eliminated by traditional processes. Emerging bioremediation technologies, such as microbial fuel cells, bioelectrochemical systems, processes based on nano(bio)technology, natural treatment systems (viz., constructed wetlands), integrated technologies involving physicochemical/biological methods, have shown effective results at lab- and pilot-level studies. Many of these technologies are in their developmental stages, and require significant improvements in process efficiency, economics, and energy conservation. They have to meet the existing challenges and need to be refined in order to integrate them into better performing sustainable universal systems.

Textile wastewater contains numerous xenobiotic compounds which have several detrimental effects on aquatic and terrestrial ecosystems. Therefore, the adequate treatment of textile wastewater is essential. This study elucidated the biodegradation of raw textile effluent (RTE) in an upflow fixed-film microaerophilic bioreactor (UFMB) along with the characterization of its bacterial community dynamics at different hydraulic retention times (HRTs) and organic loading rates (OLRs). Among the various packing materials tested in the UFMB operation, wood charcoal was found to be the most suitable packing material for the establishment of biofilm and biodegradation of RTE. The steady-state performance of UFMB having wood charcoal as packing material achieved 81.97% of American dye manufacturers institute (ADMI) colour index removal, 73.08% of biochemical oxygen demand (BOD) removal and 80.47% of chemical oxygen demand (COD) removal at 2d HRT. Whereas, upon integration of the UFMB with the sequential aerobic bioreactor (UFMB-AB system), achieved better performances with 98.6% COD, 98% ADMI and 92% BOD removal from the RTE. Additionally, the combined UFMB-AB system effectively removed other contaminants such as sulphate, phenolics and nitrogenous compounds in the RTE. The biofilm was synergistically established by the bacterial community DR4 and the native community of RTE. In response to different HRTs and OLRs, the UFMB bacterial biofilm community experienced various shifts in its composition. However, a core microbiome persisted throughout the bioreactor operation. The imputed metagenome analysis of the established UFMB biofilm using phylogenetic investigation of communities by unobserved state reconstruction (PICRUSt), revealed the presence of several xenobiotic degradation and metabolism pathways with an abundance of various different oxidoreductase genes responsible for the biodegradation of dyes and other organic pollutants present in the RTE.

This work studied eco-electrogenic treatment of real dyestuff wastewater along with characterization of electrode-enriched microbial community structures in Fimbristylis dichotoma planted closed-circuit constructed wetland-microbial fuel cell (CW-MFC) system. The CW-MFC-2 (experimental system) achieved 82.2 ± 1.7% ADMI removal and 70 ± 2% COD reduction; that were found to be 9% and 7.4% higher than the standalone constructed wetland (CW) system (bioremediation control) respectively. Likewise, the CW-MFC-2 system achieved maximum power density of 198.8 mW/m2, which was 85.6 ± 2.47% higher than the CW-MFC-1 system (eco-electricity control). Quantitative reverse transcription PCR (qRT-PCR) assays revealed significant down-regulation of hepatic oxidative stress response biomarker genes in Oreochromis niloticus exposed to CW-MFC-2 system treated dyestuff wastewater as compared with untreated wastewater. The biofilms associated with the anode and cathode of the CW-MFC-2 system exhibited selective enrichment of electrochemically active and dye degrading microbial communities.

This study evaluated Cr(VI) biosorption by a halotolerant gram-negative bacterium Halomonas sp. DK4 isolated from chrome electroplating sludge. The bacterium could withstand high concentrations of Cr(VI) exhibiting a minimal inhibitory concentration (MIC) of 250 mg/L. Plackett-Burman design confirmed glucose, KH2PO4, NaCl, inoculum size, and initial Cr(VI) concentration as significant variables influencing the Cr(VI) removal ability of the bacterium. The suspended culture of Halomonas sp. DK4 was able to remove 81% (100 mg/L) of Cr(VI) in optimized MSM medium from aqueous solutions within 48 h. The bacterium also removed 59% Cr(VI) in the presence of 15% NaCl concentration within 72 h. The main mechanism involved in Cr(VI) removal by Halomonas sp. DK4 was determined to be biosorption which was best explained using the Langmuir isotherm model, wherein the maximum adsorption of 150.7 mg/g was observed under equilibrium conditions. Kinetic studies reveal that chemisorption of Cr(VI) by Halomonas sp. DK4 was a rate-limiting process which followed pseudo-second-order kinetics (R2 = 0.99). Bacterial biomass exhibited maximum adsorption of 70.3% Cr(VI) at an initial concentration of 100 mg/L under optimal conditions. Fourier transform infrared spectroscopy (FTIR) analysis confirmed the presence of hydroxyl, carboxyl, amide, and phosphate groups on the bacterial surface which may be involved in Cr(VI) adsorption. Scanning electron microscopy coupled energy dispersive X-ray (SEM-EDX) analysis revealed morphological changes in the bacterial cell and accumulation of Cr(VI) on the cell surface. These results suggest the potential application of Halomonas sp. DK4 in the removal of Cr(VI) from saline chromium-containing industrial wastewaters.

Wastewaters are extensively generated on a daily basis from domestic and industrial sources across the globe; posing several challenges such as water crisis and environmental deterioration. Therefore, development of sustainable and energy-efficient wastewater treatment systems is sought after as a plausible solution to this problem. Recent research on microbial electrochemical technologies has shown initial success for simultaneous treatment of wastewaters with the recovery of clean energy and reclaiming usable water. Researchers have developed various configurations, electrode assemblies, and designs of microbial fuel cell (MFC) systems for treatment of industrial/domestic wastewaters using indigenous or enriched electrogenic microorganisms. From the conventional single and dual-chamber MFC systems to integrated hybrid MFCs, from lab-scale to pilot-scale level, various advancements have been made for wastewater treatment and power generation in the recent years. This chapter highlights the applications of MFC systems in treatment of different types of wastewaters.

The organisms on Earth always live in a multidimensional chemical and physical niche space. Many discoveries in the last century have tremendously expanded the range of “habitable” niches, and the environment which was considered as “nonhabitable” was found to be viable. The extremophilic microorganisms are constantly subjected to extreme environments, where they often experience high and low temperatures, high salt concentrations, low nutrient availability, abnormal atmospheric pressure, high amount of natural radiations, and other extremities, which is difficult for human and other eukaryotes to survive. To sustain the life in these environments, the indigenous microorganisms have evolved number of adaptation mechanisms with regard to metabolic activities, survival, perpetuation, and protection strategies. Various studies have provided insightful observations about extremophiles; however, advance genomics, proteomics, and sequencing technologies have started revealing the most astonishing features of life under extreme conditions.

SummaryAn optimal gut microbiota influences many beneficial processes in the metazoan host. However, the molecular mechanisms that mediate and function in symbiont-induced host responses have not yet been fully characterized. Here, we report that cellular ROS enzymatically generated in response to contact with lactobacilli in both mice and Drosophila has salutary effects against exogenous insults to the intestinal epithelium via the activation of Nrf2 responsive cytoprotective genes. These data show that the xenobiotic-inducible Nrf2 pathway participates as a signaling conduit between the prokaryotic symbiont and the eukaryotic host. Indeed, our data imply that the capacity of lactobacilli to induce redox signaling in epithelial cells is a highly conserved hormetic adaptation to impel cellular conditioning to exogenous biotic stimuli. These data also highlight the role the microbiota plays in eukaryotic cytoprotective pathways and may have significant implications in the characterization of a eubiotic microbiota.

Around the World, metal pollution is a major problem. Conventional practices of toxic metal removal can be ineffective and/or expensive, delaying and exacerbating the crisis. Those communities dealing with contamination must be aware of the fundamentals advances of microbe-mediated metal removal practices because these methods can be easily used and require less remedial intervention. This book describes innovations and efficient applications for metal bioremediation for environments polluted by metal contaminates.

Prokaryotes and lower eukaryotes, such as yeasts, utilize two-component signal transduction pathways to adapt cells to environmental stress and to regulate the expression of genes associated with virulence. One of the central proteins in this type of signaling mechanism is the phosphohistidine intermediate protein Ypd1. Ypd1 is reported to be essential for viability in the model yeast Saccharomyces cerevisiae . We present data here showing that this is not the case for Candida albicans . Disruption of YPD1 causes cells to flocculate and filament constitutively under conditions that favor growth in yeast form. To determine the function of Ypd1 in the Hog1 mitogen-activated protein kinase (MAPK) pathway, we measured phosphorylation of Hog1 MAPK in ypd1 Δ/Δ and wild-type strains of C. albicans . Constitutive phosphorylation of Hog1 was observed in the ypd1 Δ/Δ strain compared to the wild-type strain. Furthermore, fluorescence microscopy revealed that green fluorescent protein (GFP)-tagged Ypd1 is localized to both the nucleus and the cytoplasm. The subcellular segregation of GFP-tagged Ypd1 hints at an important role(s) of Ypd1 in regulation of Ssk1 (cytosolic) and Skn7 (nuclear) response regulator proteins via phosphorylation in C. albicans . Overall, our findings have profound implications for a mechanistic understanding of two-component signaling pathways in C. albicans , and perhaps in other pathogenic fungi.

Treatment of raw textile effluent (RTE) is very difficult, due to its inherent heterogeneous, low-biodegradable and toxic compositions. Pure and mixed microbial cultures have limited metabolic capabilities in effective mineralization of complex RTE. Therefore, in this study a novel bacterial community DR4 was enriched directly into a complex RTE consisting of 27 different dyes using textile dye polluted soil as an inoculum. The rigorous enrichment process resulted in acclimatization of a taxonomically distinct bacterial population, with an abundance of the genus Comamonas in the bacterial community DR4 as compared to the abundance of Pseudomonas in the RTE respectively, as revealed by high-throughput 16S rRNA gene (V3–V4 region) sequencing. Microaerophilic treatment of RTE by enriched bacterial community DR4, in the presence of optimized electron donor (sucrose) and nitrogen source (yeast extract) resulted in 88% of American Dye Manufacturer's Institute (ADMI) removal and 98% of Chemical oxygen demand (COD) reduction within 32 h at 37 °C. In silico prediction of the functional genes within bacterial community DR4 was made by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis. The PICRUSt analysis revealed high abundance of xenobiotic degradation and metabolism genes. The predicted functional genes and textile dye degradation pathways were further validated using Ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared (FTIR) spectroscopy and High Resolution Liquid Chromatography coupled with Mass Spectrometry (HR-LCMS) based characterization of textile dye degradation metabolites. The activity of azoreductases in the cell-free extracts (CFE) of the enriched bacterial community DR4 was induced by 1.83–7.81 folds in the presence of representative textile dyes as compared to uninduced samples, which confirmed their role in textile effluent decolourization. The degradation of four representative azo dyes present in RTE such as Disperse orange 30, Reactive red 152, Direct blue 2 and Acid brown 15 depicted symmetric degradation of azo bonds by bacterial community DR4.

Background & Aims There is evidence from clinical studies that compromised intestinal epithelial permeability contributes to the development of nonalcoholic steatohepatitis (NASH), but the exact mechanisms are not clear. Mice with disruption of the gene ( F11r ) encoding junctional adhesion molecule A (JAM-A) have defects in intestinal epithelial permeability. We used these mice to study how disruption of the intestinal epithelial barrier contributes to NASH. Methods Male C57BL/6 (control) or F11r -/- mice were fed a normal diet or a diet high in saturated fat, fructose, and cholesterol (HFCD) for 8 weeks. Liver and intestinal tissues were collected and analyzed by histology, quantitative reverse-transcription polymerase chain reaction, and flow cytometry. Intestinal epithelial permeability was assessed in mice by measuring permeability to fluorescently labeled dextran. The intestinal microbiota were analyzed using 16S ribosomal RNA sequencing. We also analyzed biopsy specimens from proximal colons of 30 patients with nonalcoholic fatty liver disease (NAFLD) and 19 subjects without NAFLD (controls) undergoing surveillance colonoscopy. Results F11r -/- mice fed a HFCD, but not a normal diet, developed histologic and pathologic features of severe NASH including steatosis, lobular inflammation, hepatocellular ballooning, and fibrosis, whereas control mice fed a HFCD developed only modest steatosis. Interestingly, there were no differences in body weight, ratio of liver weight:body weight, or glucose homeostasis between control and F11r -/- mice fed a HFCD. In these mice, liver injury was associated with significant increases in mucosal inflammation, tight junction disruption, and intestinal epithelial permeability to bacterial endotoxins, compared with control mice or F11r -/- mice fed a normal diet. The HFCD led to a significant increase in inflammatory microbial taxa in F11r -/- mice, compared with control mice. Administration of oral antibiotics or sequestration of bacterial endotoxins with sevelamer hydrochloride reduced mucosal inflammation and restored normal liver histology in F11r -/- mice fed a HFCD. Protein and transcript levels of JAM-A were significantly lower in the intestinal mucosa of patients with NAFLD than without NAFLD; decreased expression of JAM-A correlated with increased mucosal inflammation. Conclusions Mice with defects in intestinal epithelial permeability develop more severe steatohepatitis after a HFCD than control mice, and colon tissues from patients with NAFLD have lower levels of JAM-A and higher levels of inflammation than subjects without NAFLD. These findings indicate that intestinal epithelial barrier function and microbial dysbiosis contribute to the development of NASH. Restoration of intestinal barrier integrity and manipulation of gut microbiota might be developed as therapeutic strategies for patients with NASH.

We report here the identification and characterization of a previously uncharacterized, two-component response regulator gene (orf19.5843) from Candida albicans . Because of its apparent functions in stress adaptation, we have named this gene SRR1 ( s tress r esponse r egulator 1). Disruption of SRR1 causes defects in hyphal development, reduced resistance to stress, and severe virulence attenuation in the mouse model of disseminated candidiasis.

Candida glabrata owes its success as a pathogen, in part, to a large repertoire of adhesins present on the cell surface. Our current knowledge of C. glabrata adhesins and their role in the interaction between host and pathogen is limited to work with only a single family of epithelial adhesins (Epa proteins). Here, we report on the identification and characterization of a family of glycosylphosphatidylinositol-anchored cell wall proteins in C. glabrata. These proteins are absent in both Saccharomyces cerevisiae and Candida albicans, suggesting that C. glabrata has evolved different mechanism(s) for interaction with host cells. In the current study, we present data on the characterization of Pwp7p (PA14 domain containing Wall Protein) and Aed1p (Adherence to Endothelial cells) of this family in the interaction of C. glabrata with human umbilical vein endothelial cells. The deletion of C. glabrata genes PWP7 and AED1 results in a significant reduction in adherence to endothelial cells compared with the wild-type parent. These data indicate that C. glabrata utilizes these proteins for adherence to endothelial cells in vitro.

Microbial bioremediation has been well-demonstrated as an ecofriendly and cost-competitive strategy for elimination of xenobiotic and or anthropogenic compounds from the polluted environments. However, successful execution of these versatile bioremediation strategies requires a thorough understanding of factors governing the growth, metabolism, dynamics and functions of indigenous microbial communities at contaminated sites. Recent innovative breakthroughs in genotypic profiling, ultrafast genome pyrosequencing, metagenomics, metatranscriptomics, metaproteomics and metabolomics along with bioinformatics tools have provided crucial in-sights of microbial communities and their mechanisms in bioremediation of environmental pollutants. Moreover, advances in these technologies have significantly improved the process of efficacy determination and implementation of microbial bioremediation strategies. The current review is focused on application of these molecular and "-omics" technologies in gauging the innate microbial community structures, dynamics and functions at contaminated sites or pollution containment facilities.

Bacterial consortium-AIE2 with a capability of contemporaneous Cr(VI) reduction and azo dye RV5 decolourization was developed from industrial wastewaters by enrichment culture technique. The 16S rRNA gene based molecular analyses revealed that the consortium bacterial community structure consisted of four bacterial strains namely, Alcaligenes sp. DMA, Bacillus sp. DMB, Stenotrophomonas sp. DMS and Enterococcus sp. DME. Cumulative mechanism of Cr(VI) reduction by the consortium was determined using in vitro Cr(VI) reduction assays. Similarly, the complete degradation of Reactive Violet 5 (RV5) dye was confirmed by FTIR spectroscopic analysis. Consortium-AIE2 exhibited simultaneous bioremediation efficiencies of (97.8 ± 1.4) % and (74.1 ± 1.2) % in treatment of both 50 mg l−1 Cr(VI) and RV5 dye concentrations within 48 h of incubation at pH 7 and 37°C in batch systems. Continuous bioreactor systems achieved simultaneous bioremediation efficiencies of (98.4 ± 1.5) % and (97.5 ± 1.4) % after the onset of steady-state at 50 mg l−1 input Cr(VI) and 25 mg l−1 input RV5 concentrations, respectively, at medium dilution rate (D) of 0.014 h−1. The 16S rRNA gene copy numbers in the continuous bioreactor as determined by real-time PCR assay indicated that Alcaligenes sp. DMA and Bacillus sp. DMB dominated consortium bacterial community during the active continuous bioremediation process.

Three efficient Cr(VI) reducing bacterial strains were isolated from Cr(VI) polluted landfill and characterized for in vitro Cr(VI) reduction. Phylogenetic analysis using 16S rRNA gene sequencing revealed that the newly isolated strains G1DM20, G1DM22 and G1DM64 were closely related to Bacillus cereus, Bacillus fusiformis and Bacillus sphaericus, respectively. The suspended cultures of all Bacillus sp. exhibited more than 85% reduction of 1000 microM Cr(VI) within 30 h. The suspended culture of Bacillus sp. G1DM22 exhibited an ability for continuous reduction of 100 microM Cr(VI) up to seven consecutive inputs. Assays with the permeabilized cells and cell-free extracts from each of Bacillus sp. demonstrated that the hexavalent chromate reductase activity was mainly associated with the soluble fraction of cells and expressed constitutively. The Cr(VI) reduction by the cell-free extracts of Bacillus sp. G1DM20 and G1DM22 was maximum at 30 degrees C and pH 7 whereas, Bacillus sp. G1DM64 exhibited maximum Cr(VI) reduction at pH 6. Addition of 1mM NADH enhanced the Cr(VI) reductase activity in the cell-free extracts of all three isolates. Amongst all three isolates tested, crude cell-free extracts of Bacillus sp. G1DM22 exhibited the fastest Cr(VI) reduction rate with complete reduction of 100 microM Cr(VI) within 100 min. The apparent K(m) and V(max) of the chromate reductase activity in Bacillus sp. G1DM22 were determined to be 200 microM Cr(VI) and 5.5 micromol/min/mg protein, respectively. The Cr(VI) reductase activity in cell-free extracts of all the isolates was stable in presence of different metal ions tested except Hg(2+) and Ag(+).

Hexavalent chromate reductase activity was localized and characterized in vitro in cytosolic fraction of a newly isolated Pseudomonas sp. G1DM21. The suspended culture of the bacterium reduced 99.7% of 500 μM Cr(VI) and 93.06% of 1000 μM Cr(VI) in 48 h. The suspended culture repeatedly reduced 100 μM Cr(VI) within 6 h up to four consecutive inputs. The permeabilized cells of the bacterium reduced 92% of 100 μM Cr(VI) within 6 h. The cell-free extracts (CFE) reduced 90% of 100 μM Cr(VI) in 120 min. The Km and Vmax determined for chromate reductase activity in the CFE were 175 μM Cr(VI) and 1.6 μmoles/min/mg of protein, respectively, the Km and Vmax determined in the presence of 0.5 mM NADH were 150 μM Cr(VI) and 2.0 μmoles/min/mg of protein, respectively. Hexavalent chromate reductase activity was maximum at 30 °C and pH 7.0. Relative molecular mass (Mr) of the native Cr(VI) reductase in the cytosolic fraction was estimated as 61.7 kDa. The Cr(VI) reductase activity increased in the presence of metal ions like Cu2+, Mg2+, Na+ and electron donors like citrate, succinate, acetate and was significantly inhibited in the presence of metal ions like Hg2+, Ag+, Cd2+, disulfide reducers like 2-mercaptoethanol, while the respiratory inhibitors had a minute effect on the activity. Scanning probe atomic force microscopy (AFM) analysis indicates that exposure of Pseudomonas sp. G1DM21 to 1 mM Cr(VI) for 24 h, leads to an increase in cell length and height.

The mammalian intestine houses a complex microbial community, which influences normal epithelial growth and development, and is integral to the repair of damaged intestinal mucosa(1-3). Restitution of injured mucosa involves the recruitment of immune cells, epithelial migration and proliferation(4,5). Although microenvironmental alterations have been described in wound healing(6), a role for extrinsic influences, such as members of the microbiota, has not been reported. Here, we show that a distinct subpopulation of the normal mucosal-associated gut microbiota expands and preferentially colonizes sites of damaged murine mucosa in response to local environmental cues. Our results demonstrate that formyl peptide receptor 1 (FPR1) and neutrophilic NADPH oxidase (NOX2) are required for the rapid depletion of microenvironmental oxygen and compensatory responses, resulting in a dramatic enrichment of an anaerobic bacterial consortium. Furthermore, the dominant member of this wound-mucosa-associated microbiota, Akkermansia muciniphila (an anaerobic, mucinophilic gut symbiont(7,8)), stimulated proliferation and migration of enterocytes adjacent to the colonic wounds in a process involving FPR1 and intestinal epithelial-cell-specific NOX1-dependent redox signalling. These findings thus demonstrate how wound microenvironments induce the rapid emergence of 'probiont' species that contribute to enhanced repair of mucosal wounds. Such microorganisms could be exploited as potential therapeutics.

Two-component signal transduction pathways are one of the primary means by which microorganisms respond to environmental signals. These signaling cascades originated in prokaryotes and were inherited by eukaryotes via endosymbiotic lateral gene transfer from ancestral cyanobacteria. We report here that the nuclear genome of the pathogenic fungus Candida albicans contains elements of a two-component signaling pathway that seem to be targeted to the mitochondria. The C. albicans two-component response regulator protein Srr1 ( s tress r esponse r egulator 1) contains a mitochondrial targeting sequence at the N terminus, and fluorescence microscopy reveals mitochondrial localization of green fluorescent protein-tagged Srr1. Moreover, phylogenetic analysis indicates that C. albicans Srr1 is more closely related to histidine kinases and response regulators found in marine bacteria than are other two-component proteins present in the fungi. These data suggest conservation of this protein during the evolutionary transition from endosymbiont to a subcellular organelle. We used microarray analysis to determine whether the phenotypes observed with a srr1Δ/Δ mutant could be correlated with gene transcriptional changes. The expression of mitochondrial genes was altered in the srr1Δ/Δ null mutant in comparison to their expression in the wild type. Furthermore, apoptosis increased significantly in the srr1Δ/Δ mutant strain compared to the level of apoptosis in the wild type, suggesting the activation of a mitochondrion-dependent apoptotic cell death pathway in the srr1Δ/Δ mutant. Collectively, this study shows for the first time that a lower eukaryote like C. albicans possesses a two-component response regulator protein that has survived in mitochondria and regulates a subset of genes whose functions are associated with the oxidative stress response and programmed cell death (apoptosis).

Microorganisms play essential roles in nutrient cycles, interact with all living organisms and form bedrock of sustainable ecosystems. For implementation of bioremediation strategies it is essential that we understand how the environment (oxygen, water, nutrients, temperature and pH) modulates microbial activities. Microbial activities like oxidation, reduction, binding, immobilization, volatization, or transformation are carried out by enzymes such as oxidases, reductases, oxygenases and many more. Only few enzymes by their specific function are involved in bioremediation. However, there are many enzymes which by their specific role are involved in cellular metabolic functions but under stress conditions induced by anthropogens such as hydrocarbons, dyes, aromatic and xenobiotic compounds they perform alternate functions in metabolic pathways involved in biodegradation. The complete genome sequencing has become a very regular phenomenon and there is a significant augmentation in microbial genome databases. Consequently, it is possible to hypothesize the role of genes involved in bioremediation. However, to ascertain how many of them are actually involved in bioremediation we need transcriptome and proteome profiles. Cellular expression of proteins and metabolites varies with the stress and characterizing the differentially expressed molecules will provide the missing links in the degradation pathways. Innovative breakthroughs in technologies of sequencing, fingerprinting techniques, microarray and mass spectrometry along with bioinformatics tools have led a paradigm shift in characterizing microbial activities at molecular level. At the same time the use of molecular techniques has led to realization that microbial diversity is several folds higher than ever anticipated. Any one particular microorganism is incapable of processing all the metabolic reactions to degrade recalcitrant compounds, however a group of organisms form a community and collectively process all the reactions for bioremediation. Emerging fields like metagenomics, metatranscriptomics, metaproteomics and metabolomics have solved and are solving the complex biodegradation pathways. In future, applications of techniques such as lateral gene transfers, genetic engineering and protein engineering by rational or irrational experimental designs for direct or indirect evolution will develop recombinant strains with novel capabilities.

Mixed-ligand complexes of oxovanadium(IV) of the type [VOAL]*2H(2)O [where A = ciprofloxacin and L = uninegative bidentate ligands] have been synthesized and characterized using infrared spectra, electronic spectra, magnetic measurements, elemental analyses, thermal investigation, and mass spectroscopy. Here, we tried to increase an antibacterial activity of ciprofloxacin drug due to formation of mixed-ligand complexes. The complexes were found to be more potent compare to some standard drugs, ligands and metal salt against selective gram(+ve) and gram(-ve) organisms. Binding of the complexes with DNA have been investigated by spectroscopic absorption titration and viscometric techniques. The mixed-ligand complexes show good binding ability. The cleavage efficacy has been determined using gel electrophoresis method and complexes were found to be more active compared to parental ligands and metal salt.

PCR inhibitor-free metagenomic DNA of high quality and high yield was extracted from highly polluted sediments using a simple remediation strategy of adsorption and ion-exchange chromatography. Extraction procedure was optimized with series of steps, which involved gentle mechanical lysis, treatment with powdered activated charcoal (PAC) and ion-exchange chromatography with amberlite resin. Quality of the extracted DNA for molecular diversity analysis was tested by amplifying bacterial 16S rDNA (16S rRNA gene) with eubacterial specific universal primers (8f and 1492r), cloning of the amplified 16S rDNA and ARDRA (amplified rDNA restriction analysis) of the 16S rDNA clones. The presence of discrete differences in ARDRA banding profiles provided evidence for expediency of the DNA extraction protocol in molecular diversity studies. A comparison of the optimized protocol with commercial Ultraclean Soil DNA isolation kit suggested that method described in this report would be more efficient in removing metallic and organic inhibitors, from polluted sediment samples.