Extremophiles, a Nifty Tool to Face Environmental Pollution: From Exploitation of Metabolism to Genome Engineering

Extremophiles are microorganisms that populate habitats considered inhospitable from an anthropocentric point of view and are able to tolerate harsh conditions such as high temperatures, extreme pHs, high concentrations of salts, toxic organic substances, and/or heavy metals. These microorganisms have been broadly studied in the last 30 years and represent precious sources of biomolecules and bioprocesses for many biotechnological applications; in this context, scientific efforts have been focused on the employment of extremophilic microbes and their metabolic pathways to develop biomonitoring and bioremediation strategies to face environmental pollution, as well as to improve biorefineries for the conversion of biomasses into various chemical compounds. This review gives an overview on the peculiar metabolic features of certain extremophilic microorganisms, with a main focus on thermophiles, which make them attractive for biotechnological applications in the field of environmental remediation; moreover, it sheds light on updated genetic systems (also those based on the CRISPR-Cas tool), which expand the potentialities of these microorganisms to be genetically manipulated for various biotechnological purposes.

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A Review on Recent Trends in Nanomaterials and Nanocomposites for Environmental Applications

Current Analytical Chemistry ◽

10.2174/1573411016666200102112728 ◽

2020 ◽

Vol 16 ◽

Author(s):

Kannappan Panchamoorthy Gopinath ◽

Malolan Rajagopal ◽

Abhishek Krishnan ◽

Shweta Kolathur Sreerama

Keyword(s):

Environmental Pollution ◽

Environmental Remediation ◽

Carbon Capture ◽

Potential Applications ◽

Important Challenge ◽

Term Basis ◽

Short And Long Term ◽

Recent Trends ◽

Water And Soil Pollution

Background: Depletion and contamination of environmental resources such as water, air and soil caused by human activities is an increasingly important challenge faced around the world. The consequences of environmental pollution are felt acutely by all living beings, both on a short and long-term basis, thereby making methods of remediation of environmental pollution an urgent requirement. Objectives: The objective of this review is to dissect the complications caused by environmental degradation, highlight advancements in the field of nanotechnology and to scrutinize its applications in environmental remediation. Furthermore, the review aims to concisely explain the merits and drawbacks of nanotechnology compared to existing methods. Conclusion: The current and potential applications of nanomaterials and nanocomposites in the prevention, control and reduction of air, water and soil pollution and the mechanisms involved have been elucidated, as have their various merits and demerits. The applications of nanotechnology in the fields of carbon capture and agriculture have also received attention in this review.

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Biodegradation and metabolic pathway of fenvalerate by Citrobacter freundii CD-9

AMB Express ◽

10.1186/s13568-020-01128-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jie Tang ◽

Dan Lei ◽

Min Wu ◽

Qiong Hu ◽

Qing Zhang

Keyword(s):

Environmental Pollution ◽

Environmental Remediation ◽

High Efficiency ◽

Mass Spectrometry Analysis ◽

Gas Chromatography Mass Spectrometry ◽

Citrobacter Freundii ◽

16S Rrna Sequence ◽

Intracellular Enzyme ◽

Pyrethroid Insecticides ◽

Spectrometry Analysis

Abstract Fenvalerate is a pyrethroid insecticide with rapid action, strong targeting, broad spectrum, and high efficiency. However, continued use of fenvalerate has resulted in its widespread presence as a pollutant in surface streams and soils, causing serious environmental pollution. Pesticide residues in the soil are closely related to food safety, yet little is known regarding the kinetics and metabolic behaviors of fenvalerate. In this study, a fenvalerate-degrading microbial strain, CD-9, isolated from factory sludge, was identified as Citrobacter freundii based on morphological, physio-biochemical, and 16S rRNA sequence analysis. Response surface methodology analysis showed that the optimum conditions for fenvalerate degradation by CD-9 were pH 6.3, substrate concentration 77 mg/L, and inoculum amount 6% (v/v). Under these conditions, approximately 88% of fenvalerate present was degraded within 72 h of culture. Based on high-performance liquid chromatography and gas chromatography-mass spectrometry analysis, ten metabolites were confirmed after the degradation of fenvalerate by strain CD-9. Among them, o-phthalaldehyde is a new metabolite for fenvalerate degradation. Based on the identified metabolites, a possible degradation pathway of fenvalerate by C. freundii CD-9 was proposed. Furthermore, the enzyme localization method was used to study CD-9 bacteria and determine that its degrading enzyme is an intracellular enzyme. The degradation rate of fenvalerate by a crude enzyme solution for over 30 min was 73.87%. These results showed that strain CD-9 may be a suitable organism to eliminate environmental pollution by pyrethroid insecticides and provide a future reference for the preparation of microbial degradation agents and environmental remediation.

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Assessment of Long-Term Fermentability of PHA-Based Materials from Pure and Mixed Microbial Cultures for Potential Environmental Applications

Water ◽

10.3390/w13070897 ◽

2021 ◽

Vol 13 (7) ◽

pp. 897

Author(s):

Neda Amanat ◽

Bruna Matturro ◽

Marta Maria Rossi ◽

Francesco Valentino ◽

Marianna Villano ◽

...

Keyword(s):

Environmental Remediation ◽

Volatile Fatty Acids ◽

Rapid Onset ◽

Pilot Scale ◽

Point Of View ◽

Microbial Cultures ◽

Extraction And Purification ◽

Fermentation Pattern ◽

Mixed Microbial Cultures

The use of polyhydroxyalkanoates (PHA) as slow-release electron donors for environmental remediation represents a novel and appealing application that is attracting considerable attention in the scientific community. In this context, here, the fermentation pattern of different types of PHA-based materials has been investigated in batch and continuous-flow experiments. Along with commercially available materials, produced from axenic microbial cultures, PHA produced at pilot scale by mixed microbial cultures (MMC) using waste feedstock have been also tested. As a main finding, a rapid onset of volatile fatty acids (VFA) production was observed with a low-purity MMC-deriving material, consisting of microbial cells containing 56% (on weight basis) of intracellular PHA. Indeed, with this material a sustained, long-term production of organic acids (i.e., acetic, propionic, and butyric acids) was observed. In addition, the obtained yield of conversion into acids (up to 70% gVFA/gPHA) was higher than that obtained with the other tested materials, made of extracted and purified PHA. These results clearly suggest the possibility to directly use the PHA-rich cells deriving from the MMC production process, with no need of extraction and purification procedures, as a sustainable and effective carbon source bringing remarkable advantages from an economic and environmental point of view.

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Dragonfly Inspired Smart Soft Robot

10.1101/2020.04.28.067033 ◽

2020 ◽

Author(s):

Vardhman Kumar ◽

Ung Hyun Ko ◽

Yilong Zhou ◽

Jiaul Hoque ◽

Gaurav Arya ◽

...

Keyword(s):

Environmental Remediation ◽

Stimuli Responsive ◽

Complex Environments ◽

Soft Robots ◽

Responsive Materials ◽

Environmental Perturbations ◽

Integration Strategies ◽

Soft Actuators ◽

Harsh Conditions

Recent advancements in soft robotics have led to the development of compliant robots that can exhibit complex motions driven by living cells(1, 2), chemical reactions(3), or electronics(4). Further innovations are however needed to create the next generation of soft robots that can carry out advanced functions beyond locomotion. Here we describe DraBot—a dragonfly-inspired, entirely soft, multifunctional robot that combines long-term locomotion over water surface with sensing, responding, and adaptation capabilities. By integrating soft actuators, stimuli-responsive materials, and microarchitectural features, we created a circuitry of pneumatic and microfluidic logic that enabled the robot to undergo user- and environment-controlled (pH) locomotion, including navigating hazardous (acidic) conditions. DraBot was also engineered to sense additional environmental perturbations (temperature) and detect and clean up chemicals (oil). The design, fabrication, and integration strategies demonstrated here pave a way for developing futuristic soft robots that can acclimatize and adapt to harsh conditions while carrying out complex tasks such as exploration, environmental remediation, and health care in complex environments.

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Exploring the hydrolytic potential of cultured halophilic bacteria isolated from the Atacama Desert

FEMS Microbiology Letters ◽

10.1093/femsle/fnz224 ◽

2019 ◽

Vol 366 (17) ◽

Cited By ~ 6

Author(s):

Robert Ruginescu ◽

Cristina Purcărea ◽

Cristina Dorador ◽

Paris Lavin ◽

Roxana Cojoc ◽

...

Keyword(s):

Halophilic Bacteria ◽

Agar Plate ◽

Atacama Desert ◽

Industrial Processes ◽

Biotechnological Applications ◽

Bacterial Isolates ◽

Salt Tolerant ◽

Essential Step ◽

Extremophilic Microorganisms ◽

Biological Sources

ABSTRACT Considering that most industrial processes are carried out under harsh physicochemical conditions, which would inactivate enzymes from commonly isolated mesophilic organisms, current studies are geared toward the identification of extremophilic microorganisms producing enzymes resistant to extreme salt concentrations, temperature and pH. Among the extremophiles, halophilic microorganisms are an important source of salt-tolerant enzymes that can be used in varying biotechnological applications. In this context, the aim of the present work was to isolate and identify halophiles producing hydrolases from the Atacama Desert, one of the harshest environments on Earth. Isolates were recovered from halite samples and screened for the presence of seven different hydrolase activities (amylase, caseinase, gelatinase, lipase, pectinase, cellulase and inulinase) using agar plate-based assays. From a total of 23 halophilic bacterial isolates, most showed lipolytic (19 strains) and pectinolytic (11 strains) activities. The molecular identification of eight selected isolates showed a strong similarity to members of the Halomonas and Idiomarina genera. Therefore, the present study represents a preliminary, but essential, step to identify novel biological sources of extremozymes in an environment once thought to be devoid of life.

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Cathepsin D in Breast Cancer Tissue

The International Journal of Biological Markers ◽

10.1177/172460089000500407 ◽

1990 ◽

Vol 5 (4) ◽

pp. 203-206 ◽

Cited By ~ 3

Author(s):

P. Gonzalez Gancedo ◽

M.L. G-Casaus ◽

J. Ruiz Cacho ◽

F. Calero ◽

J.M. Inocente ◽

...

Keyword(s):

Breast Cancer ◽

Cathepsin D ◽

Clinical Stage ◽

Point Of View ◽

Axillary Lymph Nodes ◽

Cancer Tissue ◽

Axillary Lymph ◽

Statistical Point ◽

High Concentrations ◽

Dependent State

The cathepsin D concentration in 18 women with benign breast pathology has a cut-off value of 43 pmol/mg of protein. High values have been detected in two cases of chronic mastitis. These high values of cathepsin D were found in a study of 62 patients suffering from breast cancer and are independent of the hormone dependent state of the tumour. The cathepsin D concentration may have a prognostic function in breast cancer determination, as high concentrations are found in combination with other prognostic factors such as clinical stage, size of the tumour, state of the axillary lymph nodes and in the histological differentiation grade, where from a statistical point of view, the combination is important.

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The Fumigation of Ships with Liston's Cyanide Fumigator

Journal of Hygiene ◽

10.1017/s0022172400031430 ◽

1923 ◽

Vol 21 (3) ◽

pp. 199-219

Author(s):

W. Glen Liston ◽

S. N. Goré

Keyword(s):

Artificial Ventilation ◽

Point Of View ◽

High Concentrations ◽

Time Required ◽

Different Parts ◽

At Will

(1) These experiments prove that the fumigator is safer to use than the dumping fixture, because high concentrations of the poison gas are avoided, so that dangerous pockets are not developed.(2) The poison gas is more evenly distributed over the different parts of the section of the ship under treatment.(3) High concentrations, however, can be developed^ at will in any part which requires special attention.(4) The maximum concentrations of the poison gas were obtained in every part of the section in a shorter time, when the fumigator was used, than when the dumping fixture was employed.(5) The artificial ventilation caused by the fan, which is capable of blowing into the section 500 to 1000 cubic feet of fresh air per minute, according to the speed of the motor, materially assists the rapid clearing of the poison gas from the ship, after it has accomplished its work. It is thus possible to complete the fumigation and ventilation of a ship in 3 hours using the cyanide fumigator, while more than 4 hours are required for the dumping fixture.(6) Even more important is the fact that smaller quantities of cyanide can be used with greater efficiency in the fumigator, than larger quantities, with less efficiency in the dumping fixture.(7) The general conclusion is arrived at, that, from the point of view of efficiency, safety and economy, the fumigator is superior to the dumping fixture. Creel has shown that, in respect to the time required for completing the fumigation, and in respect to the thoroughness of the process, both in killing rats and insects, the dumping fixture is superior to the Clayton gas machine. It follows, therefore, that the cyanide fumigator is very much superior in these respects to the Clayton gas machine.

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Investigation of the Kinetic Regularities of the Process of Biodegradation of Betaine Surfactant by Bacteria of the Genus Pseudomonas

Applied Sciences ◽

10.3390/app11198939 ◽

2021 ◽

Vol 11 (19) ◽

pp. 8939

Author(s):

Anastasia S. Burlachenko ◽

Olesya V. Salishcheva ◽

Lyubov S. Dyshlyuk ◽

Alexander Y. Prosekov

Keyword(s):

Kinetic Data ◽

Industrial Wastewater ◽

Surfactant Concentration ◽

Time Interval ◽

Organic Substances ◽

High Concentration ◽

First Order ◽

High Concentrations ◽

Biological Decomposition ◽

Toxic Organic Substances

Surfactants are extremely common organic compounds that enter the environment in large quantities in the form of household and industrial wastewater. The toxicity of surfactants for biological systems, the high concentration of substances and the duration of the bioremediation process of polluted ecosystems requires improving the biotechnology of microbial wastewater treatment for surfactants. The purpose of this work is to study the kinetic laws of the reaction of the biological decomposition of betaine surfactants. Pseudomonas bacteria were used as bio-destructors of the surfactants. Kinetic data were obtained to create the possibility of further optimization of research on the biodegradation of toxic organic substances. The strains that were promising destructors of cocamidopropylbetaine were selected. The toxicity of high concentrations of surfactants in relation to microorganisms of the genus Pseudomonas was proven. Safe values of the surfactant concentration for conducting biodegradation tests were found. A kinetic model of the biodestructive process was constructed. It proves that the processes of biodegradation are described by a kinetic equation of the first order. With the derived equation, it is possible to determine the time interval of biodegradation of cocamidopropylbetaine to the specified values by means of mathematical calculations.

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Study on the Influence of Tourism Activities on Nature Reserves in China and Its Countermeasures

Learning & Education ◽

10.18282/l-e.v9i2.1429 ◽

2020 ◽

Vol 9 (2) ◽

pp. 145

Author(s):

Qi Ji

Keyword(s):

Environmental Pollution ◽

Industrial Structure ◽

Negative Impact ◽

Economic Value ◽

Point Of View ◽

Nature Reserves ◽

Negative Effects ◽

Continuous Increase ◽

Culture Development ◽

The Impact

China’s “industrial restructuring” has expanded the proportion of the tertiary industry in the economy and promoted the development of local tourism. The ongoing “industrial structure upgrading” is intended to make the industry bigger and stronger, which will promote the growth of local tourism. As a tourist resort, nature reserves have been attracting a large number of tourists and have great development potential and economic value. Under this situation, various management agencies of nature reserves have successively carried out tourism activities and carried out tourism development and construction. However, there is no doubt that both tourism activities and development will have an impact on the ecological system of nature reserves. The existing legal system of nature reserves in China emphasizes the prohibition of behaviors that directly destroy the ecological environment and ignores the impact of human tourism activities. The continuous increase in the number of tourism in our country, brought on nature reserves of rich tourist income at the same time, a large number of facts show that tourism has become a source of environmental pollution, so it is necessary for tourism environmental pollution the main way to do a summary and its particularity, summing up the basic law of tourism affect the environment, thus provide the basis for strengthening the environmental protection from the point of view of tourism management. The emergence and development of tourism culture is inseparable from the influence of the environment, and tourism culture also affects the environment. The negative effects and negative effects of tourism culture development on the environment are becoming more and more evident, which has aroused people’s general concern. In recent years, the negative impact of tourism and cultural activities on the environment has been paid much attention to by many scholars at home and abroad. This paper discusses the impact of tourism activities on nature reserves, and discusses the causes of this problem, so as to analyze the strategies to ensure the harmony and order of nature reserves in tourism activities.

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Arsenic Trioxide Selectively Induces Acute Promyelocytic Leukemia Cell Apoptosis Via a Hydrogen Peroxide-Dependent Pathway

Blood ◽

10.1182/blood.v94.6.2102 ◽

1999 ◽

Vol 94 (6) ◽

pp. 2102-2111 ◽

Cited By ~ 383

Author(s):

Yongkui Jing ◽

Jie Dai ◽

Ruth M.E. Chalmers-Redman ◽

Willam G. Tatton ◽

Samuel Waxman

Keyword(s):

Acute Promyelocytic Leukemia ◽

Leukemia Cell ◽

Promyelocytic Leukemia ◽

Point Of View ◽

Leukemic Cells ◽

Monocytic Leukemia ◽

Cytochrome C Release ◽

Nb4 Cells ◽

H2o2 Content ◽

High Concentrations

Abstract Low concentrations of As2O3 (≤1 μmol/L) induce long-lasting remission in patients with acute promyelocytic leukemia (APL) without significant myelosuppressive side effects. Several groups, including ours, have shown that 0.5 to 1 μmol/L As2O3 induces apoptosis in APL-derived NB4 cells, whereas other leukemic cells are resistant to As2O3 or undergo apoptosis only in response to greater than 2 μmol/L As2O3. In this report, we show that the ability of As2O3 to induce apoptosis in leukemic cells is dependent on the activity of the enzymes that regulate cellular H2O2 content. Thus, NB4 cells have relatively low levels of glutathione peroxidase (GPx) and catalase and have a constitutively higher H2O2content than U937 monocytic leukemia cells. Glutathione-S-transferase π (GSTπ), which is important for cellular efflux of As2O3, is also low in NB4 cells. Moreover, As2O3 further inhibits GPX activity and increases cellular H2O2 content in NB4 but not in U937 cells. Selenite pretreatment of NB4 cells increases the activity of GPX, lowers cellular H2O2 levels, and renders NB4 cells resistant to 1 μmol/L As2O3. In contrast, concentrations of As2O3 that alone are not capable of inducing apoptosis in NB4 cells induce apoptosis in the presence of the GPx inhibitor mercaptosuccinic acid. Similar effects are observed by modulating the activity of catalase with its inhibitor, aminotriazol. More important from a therapeutic point of view, U937 and HL-60 cells, which require high concentrations of As2O3 to undergo apoptosis, become sensitive to low, clinically acceptable concentrations of As2O3 when cotreated with these GPx and catalase inhibitors. The induction of apoptosis by As2O3 involves an early decrease in cellular mitochondrial membrane potential and increase in H2O2 content, followed by cytochrome c release, caspase 3 activation, DNA fragmentation, and the classic morphologic changes of apoptosis.

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