Polyphosphate Kinase Activity during Phosphate Uptake by Bacteria

Polyphosphate kinase, one of the key enzymes for polyphosphate accumulation in bacteria, has been investigated in pure culture and activated sludge samples. Three bacterial species (Acinetobacter lwoffi, A. phosphadevorus and Pseudomonas fluorescens) appeared to have a polyphosphate kinase activity (between 0.3 and 4.7 nM of P04 transferred per minute and per mg of proteins). However tests carried out on Aeromonas hydrophila, Bacillus subtilis, E. coli and Serratia sp. showed these species did not have any measurable polyphosphate kinase activity. Enzyme activity in bacteria is dependent on environmental conditions and can be induced, in particular, by anaerobic stress, even without modification of extracellular phosphate concentrations. Most of the activated sludge samples taken from laboratory pilot plants achieving good phosphorus removal did not present any measurable polyphosphate kinase activity. Such poor results can be related to low numbers of phosphorus removing bacteria and inhibitory molecules in sludge extracts. The only observed activity was in pretreated sludges (washed sludges) and in sludges submitted in a batch reator to phosphate starvation. However, in these, enzyme activity was at least 20 times lower than those measured in pure culture of A. lwoffi. Polyphosphate kinase induction is a complicated and time consuming method which has to be used only in the research field. At the present time our results show that sludge phosphate uptake potential cannot be predicted by the measure of induction of polyphosphate kinase activity.

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Contribution of Pseudomonas spp. to phosphorus uptake in the anoxic zone of an anaerobic-anoxic-aerobic continuous activated sludge system

Water Science & Technology ◽

10.2166/wst.2001.0034 ◽

2001 ◽

Vol 43 (1) ◽

pp. 139-146 ◽

Cited By ~ 5

Author(s):

B. W. Atkinson ◽

D. D. Mudaly ◽

F. Bux

Keyword(s):

Activated Sludge ◽

Phosphorus Removal ◽

Phosphate Uptake ◽

Phosphorus Uptake ◽

Bulk Liquid ◽

Anoxic Zone ◽

Mixed Liquor ◽

Pseudomonas Spp ◽

Activated Sludge System ◽

Polyphosphate Accumulation

A continuously operated laboratory-scale (32 L) nitrification denitrification biological excess phosphorus removal (NDBEPR) activated sludge system (modeled on the 3-stage Phoredox configuration) was maintained for 140 d. The transition from a non-biological excess phosphorus removal (BEPR) sludge to one exhibiting a strong BEPR mechanism was monitored. Mixed liquor seed inoculum was obtained from a full-scale single aerobic activated sludge installation and subjected to conditions conducive to BEPR, i.e. increasing influent acetate (HAc) concentrations. At a sludge age of 10 d with 100% HAc feed, the system was capable of removing a maximum of ca. 40 mgPO4–P/L from the bulk liquid; P/VSS of ca. 0.27 (mgP/mgVSS); and VSS/TSS of 0.53 (mgVSS/mgTSS) in the aerobic zone was attained. Although typical BEPR phosphorus transformation patterns were routinely observed, i.e. anaerobic phosphate release and aerobic phosphate uptake, phosphate uptake in the anoxic zone was also recorded indicating the presence of denitrifying phosphorus accumulating organisms (DPAOs) in the sludge community. The microbial community was screened (using both isolation and direct methods of analysis) for the presence of Pseudomonas spp. as this genus is known to perform both polyphosphate accumulation and denitrification processes. Isolation of anoxic mixed liquor bacteria on solid media and identification using the API 20NE system resulted in the total dominance of the Pseudomonads (>50%). However, direct fluorescent in situ hybridizations (FISH) revealed that Pseudomonas spp. only constituted ca. 3% of the total bacterial community indicating that other bacterial genera are contributing to simultaneous polyphosphate accumulation and denitrification processes in the anoxic zones of NDBEPR systems.

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Stimulation of phosphate uptake and polyphosphate accumulation by activated sludge microorganisms in response to sulfite addition

Water Science & Technology ◽

10.2166/wst.2011.223 ◽

2011 ◽

Vol 63 (4) ◽

pp. 649-653 ◽

Cited By ~ 1

Author(s):

M. W-Y. Lai ◽

A. N. Kulakova ◽

J. P. Quinn ◽

J. W. McGrath

Keyword(s):

Activated Sludge ◽

Phosphate Uptake ◽

Sodium Sulfite ◽

Fold Increase ◽

Phosphate Removal ◽

Intracellular Accumulation ◽

Reduced Sulfur Compounds ◽

Sulfur Oxidizing ◽

Polyphosphate Accumulation ◽

Stimulation Of

Enhanced phosphate removal from wastewaters is dependent on the synthesis and intracellular accumulation of polyphosphate by sludge microorganisms. However the role played by polyphosphate in microbial metabolism and the factors that trigger its formation remain poorly-understood. Many examples of the accumulation of the biopolymer by environmental microorganisms are documented; these include a recent report of the presence of large polyphosphate inclusions in sulfur-oxidizing marine bacteria. To investigate whether any link might exist outside the marine environment between the presence of reduced sulfur compounds and enhanced levels of microbial phosphate uptake and polyphosphate accumulation, activated sludge cultures were grown under laboratory conditions in media that contained sulfite, thiosulfate, hydrosulfite or tetrathionate. Only in the presence of sulfite was there any evidence of a stimulatory effect; in medium that contained 0.5 mM sodium sulfite some 17% more phosphate was removed by the sludge, whilst there was an almost two-fold increase in intracellular polyphosphate levels. No indications of sulfite toxicity were observed.

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Parameters for Measuring the Activity and Viability of Activated Sludge

Water Quality Research Journal ◽

10.2166/wqrj.1974.022 ◽

1974 ◽

Vol 9 (1) ◽

pp. 235-249 ◽

Cited By ~ 1

Author(s):

S.G. Nutt ◽

K.L. Murphy

Keyword(s):

Organic Carbon ◽

Activated Sludge ◽

Biological System ◽

Analytical Methods ◽

Heterogeneous System ◽

Removal Rate ◽

Bacterial Species ◽

Atp Content ◽

Culture Studies ◽

Activated Sludge System

Abstract Conventional wastewater parameters are accepted as inadequate estimates of the condition of activated sludge but numerous other indices have been suggested as specific measurements of the activity and viability of the biomass. Literature in the related fields of microbiology and biochemistry were reviewed in order to select the most appropriate activity parameters for application to a heterogeneous biological material. Modified analytical methods were applied to a well-controlled biological system containing a single predominant bacterial species to evaluate the relative merit of each as an indicator of viability and activity. The potential of each parameter in a complex heterogeneous system was determined by monitoring each index in a bench activated sludge system. The predominant culture studies indicated that the ATP content of the biomass and the dehydrogenase activity were potential indicators of cell viability in a simple system. However, in the complex activated sludge system, only the ATP content showed significant correlation to the organic carbon removal rate.

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Verification of anoxic phosphate uptake as the main biochemical mechanism of the “dephanox” process

Water Science & Technology ◽

10.2166/wst.1997.0365 ◽

1997 ◽

Vol 35 (10) ◽

pp. 87-94 ◽

Cited By ~ 7

Author(s):

R. Sorm ◽

J. Wanner ◽

R. Saltarelli ◽

G. Bortone ◽

A. Tilche

Keyword(s):

Activated Sludge ◽

Nutrient Removal ◽

Uptake Rate ◽

Phosphate Uptake ◽

Biochemical Mechanism ◽

Batch Experiments ◽

Batch Tests ◽

Genetic Probes ◽

Activated Sludge Systems ◽

Removal System

The phenomenon of anoxic phosphate uptake with simultaneous denitrification was studied. For this purpose kinetic batch tests have been carried out by using the activated sludge samples from three modifications of nutrient removal activated sludge systems: two based on an anaerobic-anoxic-oxic (A2/O) system and a third on an anaerobic-oxic (A/O) system. The results showed significant differences in anoxic phosphate uptake rate between activated sludge which was alternatively exposed to anoxic conditions and activated sludge from the A/O arrangement. These differences were also accompanied by different denitrification rates. Simultaneously with batch experiments the microscopic observation of activated sludge samples was carried out. Neisser and Gram stained samples showed clear differences in shape, size and distribution of polyphosphate accumulating bacteria between A2/O and A/O Processes. Moreover, experiments performed using genetic probes confirmed the differences in microbiological composition of activated sludge samples from different nutrient removal system arrangements.

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Toxicity of anionic and cationic surfactant to Acinetobacter junii in pure culture

Open Life Sciences ◽

10.2478/s11535-007-0029-7 ◽

2007 ◽

Vol 2 (3) ◽

pp. 405-414 ◽

Cited By ~ 22

Author(s):

Jasna Hrenovic ◽

Tomislav Ivankovic

Keyword(s):

Activated Sludge ◽

Pure Culture ◽

Sodium Dodecyl ◽

P Uptake ◽

Hexadecyltrimethylammonium Bromide ◽

Negative Effects ◽

Acinetobacter Junii ◽

Uptake Rates ◽

Eukaryotic Organisms ◽

P Uptake Rates

AbstractThe harmful effects of surfactants to the environment are well known. We were interested in investigating their potential toxicity in a pure culture of Acinetobacter junii, a phosphate (P)-accumulating bacterium. Results showed a high acute toxicity of sodium dodecyl sulfate (SDS) and hexadecyltrimethylammonium bromide (HDTMA) against A. junii. The estimated EC50 values of the HDTMA for the inhibition of CFUs in the pure culture of A. junii was 3.27 ± 1.12 × 10−7 mol L−1 and for the inhibition of the P-uptake rates 2.47 ± 0.51 × 10−6 mol L−1. For SDS, estimated EC50 values for the inhibition of CFUs in the pure culture of A. junii was 5.00 ± 2.95 × 10−6 mol L−1 and for the inhibition of the P-uptake rates 3.33 ± 0.96 × 10−4 mol L−1. The obtained EC50 values in the standardised yeast toxicity test using Saccharomyces cerevisiae were 3.03 ± 0.38 × 10−4 and 4.33 ± 0.32 × 10−5 mol L−1 for SDS and HDTMA, respectively. These results emphasized the need to control concentrations of surfactants entering the activated sludge system. The negative effects of these toxicants could greatly decrease populations of P-accumulating bacteria, as well as eukaryotic organisms, inhabiting activated sludge systems, which in turn could result in the decrease of the system efficiency.

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Study of Antibacterial Activity of Nanosilver-Polypropylene Composite against Contaminated Bacteria in Molasses

Materials Science Forum ◽

10.4028/www.scientific.net/msf.939.163 ◽

2018 ◽

Vol 939 ◽

pp. 163-169

Author(s):

Kittiya Pongsapasiritat ◽

Nongnapat Jumnienkul ◽

Rapeepun Dangtungee ◽

Malinee Sriariyanun

Keyword(s):

Antibacterial Activity ◽

Antibacterial Agent ◽

Bacterial Species ◽

Antibacterial Activities ◽

Research Field ◽

Total Sugar ◽

Bioethanol Production ◽

Polypropylene Composite ◽

Nanosilver Particles ◽

Sugar Degradation

The nanosilver particles are attractive in the research field of nanotechnology due to one of their applications as an effective antibacterial agent. The main objective of the current research is to inhibit the bacterial growth in the molasses to decrease the rate of total sugar degradation caused by contaminated bacteria. The polypropylene masterbatch containing with AgNPs (PP/AgNPs) was prepared and tested against contaminated bacterial species identified in molasse. The percentage of bacterial inhibition was calculated by observing the viability of bacteria cultures by using spread plate technique after treated with PP/AgNPs masterbatch in batch experiment. The concentrations of nanoparticles in masterbatch were varied to be 200, 500, 1000, 1200 and 1500 ppm. At 1500 ppm, the compromised antibacterial activities were observed in all tested bacterial species with 2-h-long exposure time. The results in this study could be further applied to fit in operation of molasse use in industrial scale in various application, including bioethanol production.

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A Stringent Analysis of Polyphosphate Dynamics inEscherichia coli

Journal of Bacteriology ◽

10.1128/jb.00070-19 ◽

2019 ◽

Vol 201 (9) ◽

Author(s):

Michael Downey

Keyword(s):

Escherichia Coli ◽

Infection Control ◽

Bacterial Species ◽

Stringent Response ◽

Industrial Applications ◽

Bacterial Cells ◽

Inescherichia Coli ◽

Content Type ◽

Polyphosphate Accumulation ◽

Inorganic Phosphates

ABSTRACTDuring stress, bacterial cells activate a conserved pathway called the stringent response that promotes survival. Polyphosphates are long chains of inorganic phosphates that modulate this response in diverse bacterial species. In this issue, Michael J. Gray provides an important correction to the model of how polyphosphate accumulation is regulated during the stringent response inEscherichia coli(M. J. Gray, J. Bacteriol, 201:e00664-18, 2019,https://doi.org/10.1128/JB.00664-18). With other recent publications, this study provides a revised framework for understanding how bacterial polyphosphate dynamics might be exploited in infection control and industrial applications.

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Causes of Increased Plasma Creatine Kinase Activity after Surgery

Clinical Chemistry ◽

10.1093/clinchem/20.3.340 ◽

1974 ◽

Vol 20 (3) ◽

pp. 340-342 ◽

Cited By ~ 11

Author(s):

Kannika S Phornphutkul ◽

Sinn Anuras ◽

Raymond S Koff ◽

Leonard B Seeff ◽

Donald L Mahler ◽

...

Keyword(s):

Creatine Kinase ◽

Enzyme Activity ◽

Drug Exposure ◽

Kinase Activity ◽

Clinical Evidence ◽

Creatine Kinase Activity ◽

Drug Reactions ◽

Ornithine Carbamoyl Transferase ◽

Elective Surgical Procedures ◽

Plasma Creatine Kinase

Abstract To determine whether drug reactions might play a role in postoperatively increased plasma enzyme activity, we measured creatine kinase (CK), and ornithine carbamoyl transferase (OCT) activities immediately before and on the 1st, 4th, and 8th day after 343 elective surgical procedures performed on 327 patients who had received various drugs pre-operatively. We saw no overt clinical evidence of muscle damage, but plasma CK activity was significantly increased on the first postoperative day. Plasma OCT activity was not significantly altered. We found no relationship between prior drug exposure and in creased CK activity, but the administration of general rather than regional anesthesia and the duration of anesthesia during surgery were closely related to increased CK activity. Halothane or succinylcholine administration during operation was also associated with a significant increase in CK activity in subjects whose pre-operative CK activity was normal. In contrast, subjects with increased pre-operative CK activities did not show this response to halothane or succinylcholine.

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Comparison of hydrolytic enzyme systems in pure culture and activated sludge under different electron acceptor conditions

Water Science & Technology ◽

10.2166/wst.1998.0659 ◽

1998 ◽

Vol 37 (4-5) ◽

pp. 335-343 ◽

Cited By ~ 21

Author(s):

Rajeev Goel ◽

Takashi Mino ◽

Hiroyasu Satoh ◽

Tomonori Matsuo

Keyword(s):

Enzyme Activity ◽

Activated Sludge ◽

Electron Acceptor ◽

Bacillus Amyloliquefaciens ◽

Enzyme System ◽

Weak Link ◽

Batch Reactor ◽

Hydrolytic Enzyme ◽

Hydrolytic Enzymes ◽

Pure Cultures

Enzymatic hydrolysis under different electron acceptor conditions in nutrient removal activated sludge treatment processes is a weak link in the Activated Sludge Model no. 2 (Henze et al., 1995). An experimental study was undertaken to gain insight into the hydrolysis process with specific focus on hydrolysis kinetics and rates under different electron acceptor conditions. Two pure cultures, Bacillus amyloliquefaciens (Gram positive) and Pseudomonas saccharophila (Gram negative) were chosen for the study. In addition, activated sludge grown in an anaerobic-aerobic system was tested for enzymatic activity using starch as the model substrate. The hydrolytic enzymes were found to be released into the bulk in pure cultures whereas the enzyme activity was found to be mainly associated with the cell surfaces in activated sludge. Further, it was observed that the development of the hydrolytic enzyme system in Bacillus amyloliquefaciens and P. saccharophila is strongly suppressed under anoxic and anaerobic conditions. However, the effect of anaerobic and aerobic incubation on hydrolytic enzyme activity in activated sludge was found to be small. Starch hydrolysis kinetic data from batch experiments with activated sludge followed substrate saturation kinetics that were linear with biomass concentration. Finally, the similar hydrolytic enzyme activities observed under anaerobic and aerobic phases of a sequencing batch reactor are explained by considering the aspects of enzyme location and enzyme system development under aerobic and anaerobic phases. It is proposed that the floc bound enzymes are recycled in a single sludge system so that an equilibrium exists between enzyme loss and synthesis at steady state.

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