Characterization of Extracellular Proteins to Explore Their Role in Bio-Flocculation for Harvesting Algal Biomass for Wastewater Treatment

2018 ◽  
pp. 229-266
Author(s):  
Surajit Debnath
Keyword(s):  
Wastewater Treatment ◽  
Algal Biomass ◽  
Extracellular Proteins

Prediction of the O2 Conditions in the Selector

1994 ◽  
Vol 29 (7) ◽  
pp. 229-237 ◽  
Author(s):  
J. Kruit ◽  
F. Boley ◽  
L. J. A. M. Jacobs ◽  
T. W. M. Wouda
Keyword(s):  
Wastewater Treatment ◽  
Pilot Plant ◽  
Wastewater Treatment Plants ◽  
Coarse Filter ◽  
Plant Research ◽  
Influent Characterization

Influent characterization and biosorption experiments were carried out with settled influent of seven wastewater treatment plants to study the influence of O2 in the selector in relation to the success of developing good settling properties of the sludge. In previous years working selectors were installed and/or pilot plant research was carried out at these wastewater treatment plants. Characterization of the influent was done with help of standard COD and BOD measurements with help of a coarse filter. The research has elucidated that the presence of O2 in the selector, at initial sludge loadings of 3.5-6.5 kg BOD/kg MLSS.d, is important for producing good settling properties of the sludge when the sum of readily biodegradable COD and rapidly hydrolysable COD is greater than 40%. When the sum of sludge COD and slow hydrolysable COD is greater than 50% an unaerated selector can be used.

In Silico Identification and Molecular Characterization of Extracellular Cathepsin L Proteases from Giardia duodenalis

2020 ◽  
Vol 17 (4) ◽  
pp. 342-351
Author(s):  
Sergio A. Durán-Pérez ◽  
José G. Rendón-Maldonado ◽  
Lucio de Jesús Hernandez-Diaz ◽  
Annete I. Apodaca-Medina ◽  
Maribel Jiménez-Edeza ◽  
...  
Keyword(s):  
In Silico ◽  
Cathepsin L ◽  
Three Dimensional ◽  
Giardia Duodenalis ◽  
Evolutionary Genetics ◽  
Extracellular Proteins ◽  
In Silico Identification ◽  
Dimensional Models ◽  
Three Dimensional Models

Background: The protozoan Giardia duodenalis, which causes giardiasis, is an intestinal parasite that commonly affects humans, mainly pre-school children. Although there are asymptomatic cases, the main clinical features are chronic and acute diarrhea, nausea, abdominal pain, and malabsorption syndrome. Little is currently known about the virulence of the parasite, but some cases of chronic gastrointestinal alterations post-infection have been reported even when the infection was asymptomatic, suggesting that the cathepsin L proteases of the parasite may be involved in the damage at the level of the gastrointestinal mucosa. Objective: The aim of this study was the in silico identification and characterization of extracellular cathepsin L proteases in the proteome of G. duodenalis. Methods: The NP_001903 sequence of cathepsin L protease from Homo sapienswas searched against the Giardia duodenalisproteome. The subcellular localization of Giardia duodenaliscathepsin L proteases was performed in the DeepLoc-1.0 server. The construction of a phylogenetic tree of the extracellular proteins was carried out using the Molecular Evolutionary Genetics Analysis software (MEGA X). The Robetta server was used for the construction of the three-dimensional models. The search for possible inhibitors of the extracellular cathepsin L proteases of Giardia duodenaliswas performed by entering the three-dimensional structures in the FINDSITEcomb drug discovery tool. Results: Based on the amino acid sequence of cathepsin L from Homo sapiens, 8 protein sequences were identified that have in their modular structure the Pept_C1A domain characteristic of cathepsins and two of these proteins (XP_001704423 and XP_001704424) are located extracellularly. Threedimensional models were designed for both extracellular proteins and several inhibitory ligands with a score greater than 0.9 were identified. In vitrostudies are required to corroborate if these two extracellular proteins play a role in the virulence of Giardia duodenalisand to discover ligands that may be useful as therapeutic targets that interfere in the mechanism of pathogenesis generated by the parasite. Conclusion: In silicoanalysis identified two proteins in the Giardia duodenalisprotein repertoire whose characteristics allowed them to be classified as cathepsin L proteases, which may be secreted into the extracellular medium to act as virulence factors. Three-dimensional models of both proteins allowed the identification of inhibitory ligands with a high score. The results suggest that administration of those compounds might be used to block the endopeptidase activity of the extracellular cathepsin L proteases, interfering with the mechanisms of pathogenesis of the protozoan parasite Giardia duodenalis.

scholarly journals Characterization of efficient xylanases from industrial-scale pulp and paper wastewater treatment microbiota

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jia Wang ◽  
Jiawei Liang ◽  
Yonghong Li ◽  
Lingmin Tian ◽  
Yongjun Wei
Keyword(s):  
Wastewater Treatment ◽  
Xylanase Activity ◽  
Pulp And Paper ◽  
Optimal Conditions ◽  
Paper Wastewater ◽  
Termite Hindgut ◽  
Uncultured Microorganisms ◽  
Metagenomic Approach ◽  
Gh10 Family

AbstractXylanases are widely used enzymes in the food, textile, and paper industries. Most efficient xylanases have been identified from lignocellulose-degrading microbiota, such as the microbiota of the cow rumen and the termite hindgut. Xylanase genes from efficient pulp and paper wastewater treatment (PPWT) microbiota have been previously recovered by metagenomics, assigning most of the xylanase genes to the GH10 family. In this study, a total of 40 GH10 family xylanase genes derived from a certain PPWT microbiota were cloned and expressed in Escherichia coli BL21 (DE3). Among these xylanase genes, 14 showed xylanase activity on beechwood substrate. Two of these, PW-xyl9 and PW-xyl37, showed high activities, and were purified to evaluate their xylanase properties. Values of optimal pH and temperature for PW-xyl9 were pH 7 and 60 ℃, respectively, while those for PW-xyl37 were pH 7 and 55 ℃, respectively; their specific xylanase activities under optimal conditions were 470.1 U/mg protein and 113.7 U/mg protein, respectively. Furthermore, the Km values of PW-xyl9 and PW-xyl37 were determined as 8.02 and 18.8 g/L, respectively. The characterization of these two xylanases paves the way for potential application in future pulp and paper production and other industries, indicating that PPWT microbiota has been an undiscovered reservoir of efficient lignocellulase genes. This study demonstrates that a metagenomic approach has the potential to screen efficient xylanases of uncultured microorganisms from lignocellulose-degrading microbiota. In a similar way, other efficient lignocellulase genes might be identified from PPWT treatment microbiota in the future.

The first sequenced Sphaerotilus natans bacteriophage– characterization and potential to control its filamentous bacterium host

2021 ◽  
Vol 97 (4) ◽  
Author(s):  
Rute Ferreira ◽  
Rui Amado ◽  
Jorge Padrão ◽  
Vânia Ferreira ◽  
Nicolina M Dias ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Bacterial Communities ◽  
Potential Application ◽  
Deleterious Effect ◽  
Wastewater Treatment Plants ◽  
Lytic Phage ◽  
Filamentous Bacterium ◽  
Sphaerotilus Natans ◽  
Isolation And Characterization

ABSTRACT Bacteriophages (phages) are ubiquitous entities present in every conceivable habitat as a result of their bacterial parasitism. Their prevalence and impact in the ecology of bacterial communities and their ability to control pathogens make their characterization essential, particularly of new phages, improving knowledge and potential application. The isolation and characterization of a new lytic phage against Sphaerotilus natans strain DSM 6575, named vB_SnaP-R1 (SnaR1), is here described. Besides being the first sequenced genome of a Sphaerotilus natans infecting phage, 99% of its 41507 bp genome lacks homology with any other sequenced phage, revealing its uniqueness and previous lack of knowledge. Moreover, SnaR1 is the first Podoviridae phage described infecting this bacterium. Sphaerotilus natans is an important filamentous bacterium due to its deleterious effect on wastewater treatment plants (WWTP) and thus, phages may play a role as novel biotechnological tools against filamentous overgrowth in WWTP. The lytic spectrum of SnaR1 was restricted to its host strain, infecting only one out of three S. natans strains and infection assays revealed its ability to reduce bacterial loads. Results suggest SnaR1 as the prototype of a new phage genus and demonstrates its potential as a non-chemical alternative to reduce S. natans DSM 6575 cells.

Detection and molecular characterization of enteric adenovirus in treated wastewater in the Brazilian Federal District

2021 ◽  
Vol 3 (7) ◽  
Author(s):  
T. S. C. Quintão ◽  
F. G. Silva ◽  
A. L. Pereira ◽  
W. N. Araújo ◽  
P. M. Oliveira ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Federal District ◽  
Treated Wastewater ◽  
Conventional Pcr ◽  
Rainfall Index ◽  
Enteric Adenovirus ◽  
Enteric Adenoviruses

AbstractHuman enteric viruses, such as enteric adenoviruses (HAdV), are known to be involved with gastrointestinal disorders, especially acute gastroenteritis. Several studies have used HAdV as an indicator of water quality, since they are considered highly stable and widely distributed viruses in water matrices. The aim of this study was to detect and genotype HAdVs in water matrices impacted by discharges of treated effluents from wastewater treatment plants (WWTPs). Wastewater treatment plants from the sanitary system of the Brazilian Federal District were assessed in 2018 and 2019. Samples were collected upstream and downstream from discharge points for each WWTP. Viral concentration based on adsorption-elution and conventional PCR was used for molecular detection, and positive samples were sequenced for phylogenetic analysis. Pluviosity data for the period in which the samples were collected were obtained. Our results demonstrated the presence of HAdVs in 27.2% (61/224) of the samples. The positivity was significantly higher in downstream samples compared to upstream. Moreover, the HAdV positivity was higher in downstream samples collected from receiving water bodies impacted by secondary-level WWTPs in comparison with those impacted by tertiary-level WWTPs. Phylogenetic analysis demonstrated the presence of genotypes 40 and 41, with prevalence of HAdV genotype 41. Despite the predominance of HAdV-41, an increasing frequency of the HAdV-40 was associated with higher pluviosity. In conclusion, this study is the first documentation in the Brazilian Federal District dealing with the prevalence and diversity of HAdVs in several WWTP, along with their correlation with rainfall index.

scholarly journals LAYERED DOUBLE HYDROXIDES: NANOMATERIALS FOR APPLICATIONS IN AGRICULTURE

2015 ◽  
Vol 39 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Luíz Paulo Figueredo Benício ◽  
Rejane Alvarenga Silva ◽  
Júnia Aparecida Lopes ◽  
Denise Eulálio ◽  
Rodrigo Morais Menezes dos Santos ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Layered Double Hydroxides ◽  
Slow Release ◽  
Structural Characteristics ◽  
Synthesis Methods ◽  
Double Hydroxides ◽  
Near Future

The current research aims to introduce Layered Double Hydroxides (LDH) as nanomaterials to be used in agriculture, with particular reference to its use as storage and slow release matrix of nutrients and agrochemicals for plant growing. Structural characteristics, main properties, synthesis methods and characterization of LDH were covered in this study. Moreover, some literature data have been reported to demonstrate their potential for storage and slow release of nitrate, phosphate, agrochemicals, besides as being used as adsorbent for the wastewater treatment. This research aims to expand, in near future, the investigation field on these materials, with application in agriculture, increasing the interface between chemistry and agronomy.

Characterization of extracellular proteins produced byAeromonas hydrophila AH-1

PROTEOMICS ◽  
2007 ◽  
Vol 7 (3) ◽  
pp. 436-449 ◽  
Author(s):  
Hong Bing Yu ◽  
Rasvinder Kaur ◽  
Simin Lim ◽  
Xian Hui Wang ◽  
Ka Yin Leung
Keyword(s):  
Extracellular Proteins
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