scholarly journals Biodiversity of anaerobic cellulolytic bacteria in landfill sites

2001 ◽  
Author(s):  
◽  
Loren Goldstone
Keyword(s):  
Cellulose Degradation ◽  
Microbial Interactions ◽  
Landfill Site ◽  
Microbial Consortia ◽  
Anaerobic Sludge ◽  
Cellulolytic Bacteria ◽  
Anaerobic Conditions ◽  
Solid Media ◽  
Harmful Effects ◽  
Anaerobic Media

Landfills play an important role in the removal of waste from the surroundings. There is a limit to the types of waste that can be recycled and the landfill becomes the final method of waste disposal. Because waste constitutes a wide variety of materials, the microbial consortia that develop within a landfill will be equally varied, depending on the type of waste deposited, the temperature of the landfill and moisture content of the waste. The metabolism of these microbial consortia can result in products that are either harmful or beneficial. In order to increase the pool of knowledge on landfill microbiology, it is important to study the various consortia that inhabit the landfill to determine the various microbial interactions that occur and subsequently to manipulate these interactions to enhance the benefits of a landfill site and reduce the harmful effects. In this research, an attempt was made to isolate anaerobic cellulolytic bacteria from a landfill site. Six waste samples, varying in age were obtained over a period of two years. Samples were excavated from a maximum depth of 4m. Samples are processed in anaerobic, phosphate buffer and cultivated in various pre-reduced anaerobic media and incubated under anaerobic conditions. Samples were also collected from other potential anaerobic sites namely, anaerobic sludge, decomposing bagasse, compost, manure, rumen and pond sediment. Results of degradation of the cellulose source (Whatman No. 1 filter paper) indicated that it was possible to cultivate cellulose-degrading microorganisms from the landfill. Zones of clearing around colonies, which would be indicative of cellulose degradation on solid media, were not obtained. Samples from the anaerobic sludge, compost and rumen showed degradation of cellulose in liquid media but not on solid media. It is concluded that the solid media used was unsuitable for the cultivation of anaerobic, cellulolytic bacteria or that the anaerobic conditions employed were not adequate to initiate the growth of the anaerobic cellulolytic bacteria.

scholarly journals INFLUENCE OF FORAGE PHENOLICS ON CELLULOLYTIC BACTERIA AND IN VITRO CELLULOSE DEGRADATION

1984 ◽  
Vol 64 (5) ◽  
pp. 39-40 ◽  
Author(s):  
V. H. VAREL ◽  
H. G. JUNG
Keyword(s):  
Key Words ◽  
Cinnamic Acid ◽  
Dry Matter ◽  
Cellulose Degradation ◽  
In Vitro Digestion ◽  
Cellulolytic Bacteria ◽  
Anaerobic Conditions

The forage phenolics, cinnamic acid and vanillin depressed in vitro dry matter disappearance of cellulose 14 and 49%, respectively. Compared to controls, the number of Bacteroides succinogenes was threefold greater for fermentations which contained vanillin. These results are contrary to those expected and vanillin-induced oxidation of anaerobic conditions may be involved. Key words: Forage phenolics, in vitro digestion, cellulolytic bacteria

Characterization of a designed synthetic autotrophic–heterotrophic consortia for fixing CO2 without light

RSC Advances ◽  
2016 ◽  
Vol 6 (81) ◽  
pp. 78161-78169 ◽  
Author(s):  
Jiajun Hu ◽  
Yiyun Xue ◽  
Jixiang Li ◽  
Lei Wang ◽  
Shiping Zhang ◽  
...  
Keyword(s):  
Microbial Interactions ◽  
Microbial Consortia ◽  
Synthetic Microbial Consortia

CO2 fixation efficiency of the devised synthetic microbial consortia with both autotrophic–autotrophic and autotrophic–heterotrophic microbial interactions were higher than the sum of theoretical CO2 fixation efficiency of the microbial components.

Aeration tank odour by dimethyl sulphoxide (DMSO) waste in sewage

2007 ◽  
Vol 55 (5) ◽  
pp. 319-326 ◽  
Author(s):  
D. Glindemann ◽  
J.T. Novak ◽  
J. Witherspoon
Keyword(s):  
Bulk Water ◽  
Sulphate Reduction ◽  
Anaerobic Sludge ◽  
Aeration Tank ◽  
Dimethyl Sulphide ◽  
Reduction Mechanism ◽  
Anaerobic Conditions ◽  
Sludge Flocs ◽  
Oxidation Resistant

Sewage plants can experience dimethyl sulphide (DMS) odour problems by at least one mg/L dimethylsulphoxide (DMSO) waste residue in plant influent, through a DMSO/DMS reduction mechanism. This bench-scale batch study simulates in bottles the role of poor aeration in wastewater treatment on the DMSO/DMS and sulphate/H2S reduction. The study compares headspace concentrations of sulphide odorants developed by activated sludge (closed bottles, half full) after six hours under anoxic versus anaerobic conditions, with 0 versus 2 mg/L DMSO addition. Anoxic sludge (0.1–2 mg/L dissolved oxygen, DO) with DMSO resulted in about 50 ppmv DMS and no other sulphide, while DMSO-free sludge was free of detectable sulphides. Anaerobic sludge (no measurable DO to the point of sulphate reduction) with DMSO resulted in 22/4/37 ppmv of H2S/methanethiol (MT)/DMS, while DMSO-free sludge resulted in 44/8/2 ppmv of H2S/MT/DMS. It is concluded that common “anoxic” aeration tank zones with measurable DO in bulk water but immeasurable DO inside sludge flocs (nitrate reducing) experience DMSO reduction to DMS that is oxidation resistant and becomes the most important odorant. Under anaerobic conditions, H2S from sulphate reduction becomes an additional important odorant. A strategy is developed that allows operators to determine from the quantity of different sulphides whether the DMSO/DMS mechanism is important at their wastewater plant.

scholarly journals Need for Laboratory Ecosystems To Unravel the Structures and Functions of Soil Microbial Communities Mediated by Chemistry

mBio ◽  
2018 ◽  
Vol 9 (4) ◽  
Author(s):  
Kateryna Zhalnina ◽  
Karsten Zengler ◽  
Dianne Newman ◽  
Trent R. Northen
Keyword(s):  
Microbial Communities ◽  
Metabolic Networks ◽  
Soil Microbial Communities ◽  
Microbial Interactions ◽  
Microbial Consortia ◽  
Cellular Biology ◽  
Model Organisms ◽  
Soil Microbial ◽  
Integrative Framework ◽  
Genome Annotations

ABSTRACTThe chemistry underpinning microbial interactions provides an integrative framework for linking the activities of individual microbes, microbial communities, plants, and their environments. Currently, we know very little about the functions of genes and metabolites within these communities because genome annotations and functions are derived from the minority of microbes that have been propagated in the laboratory. Yet the diversity, complexity, inaccessibility, and irreproducibility of native microbial consortia limit our ability to interpret chemical signaling and map metabolic networks. In this perspective, we contend that standardized laboratory ecosystems are needed to dissect the chemistry of soil microbiomes. We argue that dissemination and application of standardized laboratory ecosystems will be transformative for the field, much like how model organisms have played critical roles in advancing biochemistry and molecular and cellular biology. Community consensus on fabricated ecosystems (“EcoFABs”) along with protocols and data standards will integrate efforts and enable rapid improvements in our understanding of the biochemical ecology of microbial communities.

scholarly journals Flux Analysis of the Metabolism ofClostridium cellulolyticum Grown in Cellulose-Fed Continuous Culture on a Chemically Defined Medium under Ammonium-Limited Conditions

2001 ◽  
Vol 67 (9) ◽  
pp. 3846-3851 ◽  
Author(s):  
Mickaël Desvaux ◽  
Henri Petitdemange
Keyword(s):  
Cellulose Degradation ◽  
Lactate Production ◽  
Nitrogen Sources ◽  
Maximum Growth ◽  
Defined Medium ◽  
Flux Analysis ◽  
Specific Rate ◽  
Cellulolytic Bacteria ◽  
Limiting Nutrient ◽  
Mesophilic Bacterium

ABSTRACT An investigation of cellulose degradation by the nonruminal, cellulolytic, mesophilic bacterium Clostridium cellulolyticum was performed in cellulose-fed chemostat cultures with ammonium as the growth-limiting nutrient. At any dilution rate (D), acetate was always the main product of the catabolism, with a yield of product from substrate ranging between 37.7 and 51.5 g per mol of hexose equivalent fermented and an acetate/ethanol ratio always higher than 1. AsD rose, the acetyl coenzyme A was rerouted in favor of ethanol pathways, and ethanol production could represent up to 17.7% of the carbon consumed. Lactate was significantly produced, but with increasing D, the specific lactate production rate declined, as did the specific rate of production of extracellular pyruvate. The proportion of the original carbon directed towards phosphoglucomutase remained constant, and the carbon surplus was balanced mainly by exopolysaccharide and glycogen biosyntheses at highD values, while cellodextrin excretion occurred mainly at lower ones. With increasing D, the specific rate of carbon flowing down catabolites increased as well, but when expressed as a percentage of carbon it declined, while the percentage of carbon directed through biosynthesis pathways was enhanced. The maximum growth and energetic yields were lower than those obtained in cellulose-limited chemostats and were related to an uncoupling between catabolism and anabolism leading to an excess of energy. Compared to growth on cellobiose in ammonium-limited chemostats (E. Guedon, M. Desvaux, and H. Petitdemange, J. Bacteriol. 182:2010–2017, 2000), (i) a specific consumption rate of carbon of as high as 26.72 mmol of hexose equivalent g of cells−1h−1 could not be reached and (ii) the proportions of carbon directed towards cellodextrin, glycogen, and exopolysaccharide pathways were not as high as first determined on cellobiose. While the use of cellobiose allows highlighting of metabolic limitation and regulation of C. cellulolyticumunder ammonium-limited conditions, some of these events should then rather be interpreted as distortions of the metabolism. Growth of cellulolytic bacteria on easily available carbon and nitrogen sources represents conditions far different from those of the natural lignocellulosic compounds.

Endo-1, 4-β-glucanase and β-glucosidase of the ciliate Polyplastron multivesiculatum free of cellulolytic bacteria

1986 ◽  
Vol 32 (3) ◽  
pp. 219-225 ◽  
Author(s):  
A. Bonhomme ◽  
G. Fonty ◽  
M. J. Foglietti ◽  
D. Robic ◽  
M. Weber
Keyword(s):  
Enzymatic Activity ◽  
Isoelectric Focusing ◽  
Reducing Sugars ◽  
Proteolytic Enzymes ◽  
Cellulose Degradation ◽  
Protein Fractions ◽  
Intracellular Bacteria ◽  
Cellulolytic Bacteria ◽  
Derivatives Of ◽  
Bacterial Cellulase

To determine the contribution of protozoal activity to cellulose degradation, we maintained the ciliate Polyplastron multivesiculatum free of extracellular and intracellular cellulolytic bacteria. Control experiments to verify the absence of such bacteria were performed on cellular extracts, on filtrates, and on ciliates before lyophilization. The enzymatic activity was determined by viscometry and by determining the amount of reducing sugars produced. The enzyme was found to be an endo-1, 4- β-glucanase. Polyplastron multivesiculatum which was maintained free of extracellular and intracellular bacteria degraded soluble derivatives of cellulose and slightly degraded native cellulose. The activity was not due to intracellular bacterial cellulase, as ingested bacteria were lysed and digested by proteolytic enzymes of the protozoan. In addition, when preparing the filtrate solutions, P. multivesiculatum was maintained in culture for 5 days with Streptococcus faecalis (a facultatively anaerobic, noncellulolytic bacterium). Isoelectric focusing and chromatofocusing of lyophilized P. multivesiculatum that was free of cellulolytic bacteria yielded three protein fractions that degrade carboxymethylcellulose and hydroxyethylcellulose. Chromatofocusing also revealed the presence of two protein fractions with β-glucosidase activity.

scholarly journals Screening of Cellulolytic Bacteria from Rotten Wood of Qinling (China) for Biomass Degradation and Cloning of Cellulases from Bacillus methylotrophicus

2019 ◽  
Author(s):  
Lingling Ma ◽  
Yingying Lu ◽  
Hong Yan ◽  
Xin Wang ◽  
Yanglei Yi ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Wheat Straw ◽  
Cellulose Degradation ◽  
Good Effect ◽  
Qinling Mountains ◽  
Cellulolytic Bacteria ◽  
Biomass Degradation ◽  
Bacillus Methylotrophicus ◽  
Rotten Wood ◽  
Degradation Effect

Abstract Background Cellulosic biomass degradation still needs to be paid more attentions as bioenergy is the most likely to replace fossil energy in the future, and more evaluable cellulolytic bacteria isolation will lay a foundation for this filed. Qinling Mountains have unique biodiversity, acting as promising source of cellulose-degrading bacteria exhibiting noteworthy properties. Therefore, the aim of this work was to find potential cellulolytic bacteria and verify the possibility of the cloning of cellulases from the selected powerful bacteria. Results In present study, 55 potential cellulolytic bacteria were screened and identified from the rotten wood of Qinling Mountains. Based on the investigation of cellulase activities and degradation effect on different cellulose substrates, Bacillus methylotrophicus 1EJ7, Bacillus subtilis 1AJ3 and Bacillus subtilis 3BJ4 were further applied to hydrolyze wheat straw, corn stover and switchgrass, and the results suggested that B. methylotrophicus 1EJ7 was the most preponderant bacterium, and which also indicated that Bacillus was the main cellulolytic bacteria in rotten wood. Furthermore, scanning electron microscopy (SEM) and X-ray diffraction analysis of micromorphology and crystallinity of wheat straw also verified the significant hydrolyzation. With ascertaining the target sequence of cellulase β-glucosidase (243 aa) and endoglucanase (499 aa) were successfully heterogeneously cloned and expressed from B. methylotrophicus 1EJ7, and which performed a good effect on cellulose degradation with enzyme activity of 1670.15±18.94 U/mL and 0.130±0.002 U/mL, respectively. In addition, based on analysis of amino acid sequence, it found that β-glucosidase were belonged to GH16 family, and endoglucanase was composed of GH5 family catalytic domain and a carbohydrate-binding module of CBM3 family. Conclusions Based on the screening, identification and cellulose degradation effect evaluation of cellulolytic bacteria from rotten wood of Qinling Mountains, it found that Bacillus were the predominant species among the isolated strains, and B. methylotrophicus 1EJ7 performed best on cellulose degradation. Meanwhile, the β-glucosidase and endoglucanase were successfully cloned and expressed from B. methylotrophicus for the first time, which provided new materials of both strain and the recombinant enzymes for the study of cellulose degradation and its application in industry.

scholarly journals Formation, Development, and Cross-Species Interactions in Biofilms

2022 ◽  
Vol 12 ◽  
Author(s):  
Aihua Luo ◽  
Fang Wang ◽  
Degang Sun ◽  
Xueyu Liu ◽  
Bingchang Xin
Keyword(s):  
Species Interactions ◽  
Bacterial Infections ◽  
Early Stage ◽  
Microbial Interactions ◽  
Bacterial Survival ◽  
Chronic Infections ◽  
Immune Attack ◽  
Biofilm Development ◽  
Natural Settings ◽  
Harmful Effects

Biofilms, which are essential vectors of bacterial survival, protect microbes from antibiotics and host immune attack and are one of the leading causes that maintain drug-resistant chronic infections. In nature, compared with monomicrobial biofilms, polymicrobial biofilms composed of multispecies bacteria predominate, which means that it is significant to explore the interactions between microorganisms from different kingdoms, species, and strains. Cross-microbial interactions exist during biofilm development, either synergistically or antagonistically. Although research into cross-species biofilms remains at an early stage, in this review, the important mechanisms that are involved in biofilm formation are delineated. Then, recent studies that investigated cross-species cooperation or synergy, competition or antagonism in biofilms, and various components that mediate those interactions will be elaborated. To determine approaches that minimize the harmful effects of biofilms, it is important to understand the interactions between microbial species. The knowledge gained from these investigations has the potential to guide studies into microbial sociality in natural settings and to help in the design of new medicines and therapies to treat bacterial infections.

Influence of bacteria on rock-water interaction and clay mineral formation in subsurface granitic environments

Clay Minerals ◽  
2001 ◽  
Vol 36 (4) ◽  
pp. 599-613 ◽  
Author(s):  
K. Hama ◽  
K. Bateman ◽  
P. Coombs ◽  
V. L. Hards ◽  
A. E. Milodowski ◽  
...  
Keyword(s):  
Hard Rock ◽  
Microbial Interactions ◽  
Anaerobic Conditions ◽  
Crushed Material ◽  
Fine Grained ◽  
Rock Laboratory ◽  
Stirred Reactor ◽  
Reducing Conditions ◽  
Rock Water Interaction ◽  
Reducing Bacteria

AbstractStudies of the subsurface microbiology of the Äspö Hard Rock Laboratory, Sweden have revealed the presence of many different bacteria in the deep groundwaters which appear to maintain reducing conditions. Experiments were conducted to study the rock-water and microbial interactions. These used crushed Äspö diorite, Äspö groundwater and iron- and sulphate-reducing bacteria in flowing systems under anaerobic conditions. In column experiments, there was evidence of loss and mobilization of fine-grained crushed material (<5 μm) which had originally adhered to grain surfaces in the starting material. The mobilized fines were trapped between grains. The degree of mineralogical alteration was greater in the experiments when bacteria were present. In both column and continuously stirred reactor experiments, there is evidence for the formation of a secondary clay. These experiments have shown that microbial activity can influence rock-water interactions even in nutrient-poor conditions.

scholarly journals A Diverse Community To Study Communities: Integration of Experiments and Mathematical Models To Study Microbial Consortia

2017 ◽  
Vol 199 (15) ◽  
Author(s):  
Antonella Succurro ◽  
Fiona Wanjiku Moejes ◽  
Oliver Ebenhöh
Keyword(s):  
Mathematical Models ◽  
Theoretical Models ◽  
Theoretical Description ◽  
Microbial Interactions ◽  
Microbial Consortia ◽  
Sequencing Data ◽  
Natural Ecosystems ◽  
Theoretical Approaches

ABSTRACT The last few years have seen the advancement of high-throughput experimental techniques that have produced an extraordinary amount of data. Bioinformatics and statistical analyses have become instrumental to interpreting the information coming from, e.g., sequencing data and often motivate further targeted experiments. The broad discipline of “computational biology” extends far beyond the well-established field of bioinformatics, but it is our impression that more theoretical methods such as the use of mathematical models are not yet as well integrated into the research studying microbial interactions. The empirical complexity of microbial communities presents challenges that are difficult to address with in vivo/in vitro approaches alone, and with microbiology developing from a qualitative to a quantitative science, we see stronger opportunities arising for interdisciplinary projects integrating theoretical approaches with experiments. Indeed, the addition of in silico experiments, i.e., computational simulations, has a discovery potential that is, unfortunately, still largely underutilized and unrecognized by the scientific community. This minireview provides an overview of mathematical models of natural ecosystems and emphasizes that one critical point in the development of a theoretical description of a microbial community is the choice of problem scale. Since this choice is mostly dictated by the biological question to be addressed, in order to employ theoretical models fully and successfully it is vital to implement an interdisciplinary view at the conceptual stages of the experimental design.

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