scholarly journals Rapid Hygiene Assay Sensitive to Cumulative Adenylate Homologues Exhibits Equal or Higher Frequencies of Soil Contamination Detection than Assay Limited to ATP Detection

2021 ◽  
Author(s):  
Scott Anthony Rankin ◽  
Casey Whyte ◽  
Ting Fung Ma ◽  
Jeffrey Sindelar
Keyword(s):  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Processing Plant ◽  
Meat Processing ◽  
Statistical Process ◽  
Safety Standards ◽  
Atp Assay ◽  
Processing Facility ◽  
Sanitary Conditions ◽  
Contamination Events

Based upon regulatory and food industry-driven food safety standards, there is a need for rapid, accurate methods for assessing sanitary conditions. A commonly utilized assay is based on the assessment of the biochemical molecule, adenosine triphosphate (ATP). A more recent assay (AXP) targets the cumulative presence of ATP and its dephosphorylated homologues, adenosine diphosphate (ADP) and adenosine monophosphate (AMP). Yet, there is little information that compares the practical performance of these two assays. This work examined these two assay types with a comparative study in a Grade A dairy foods processing plant and a licensed and inspected meat processing facility. A total of 1,920 concomitant analyses were conducted with main variables of assay type, processing facility type and hygiene zone category. Statistical process control methodology was used to calculate 95% confidence control limits (CL); data beyond those limits were considered contamination events. Results demonstrated that, overall, the AXP assay detected contamination events approximately two times more often than the ATP-only based assay. This increase in the rate of contamination event detection was especially more prevalent in the meat processing facility where, across all hygienic zones, there were 38 vs. 85 contaminations events detected for the ATP and AXP assays, respectively. Across hygiene zones, the AXP data displayed either an equal or increased incidence of soil detection compared to data from the ATP assay. This study provides applied evidence that assays solely dependent on ATP concentrations are less able to detect soil contaminants under conditions that favor ATP dephosphorylation reactions.

Cleaning Conveyor Belts in the Chicken-Cutting Area of a Poultry Processing Plant with 45°C Water

2014 ◽  
Vol 77 (3) ◽  
pp. 496-498 ◽  
Author(s):  
V. M. SOARES ◽  
J. G. PEREIRA ◽  
C. M. ZANETTE ◽  
L. A. NERO ◽  
J. P. A. N. PINTO ◽  
...  
Keyword(s):  
Conveyor Belt ◽  
Hot Water ◽  
Poultry Meat ◽  
Processing Plant ◽  
Meat Processing ◽  
Work Shift ◽  
Processing Facility ◽  
Processing Plants ◽  
Conveyor Belts ◽  
Poultry Processing

Conveyor belts are widely used in food handling areas, especially in poultry processing plants. Because they are in direct contact with food and it is a requirement of the Brazilian health authority, conveyor belts are required to be continuously cleaned with hot water under pressure. The use of water in this procedure has been questioned based on the hypothesis that water may further disseminate microorganisms but not effectively reduce the organic material on the surface. Moreover, reducing the use of water in processing may contribute to a reduction in costs and emission of effluents. However, no consistent evidence in support of removing water during conveyor belt cleaning has been reported. Therefore, the objective of the present study was to compare the bacterial counts on conveyor belts that were or were not continuously cleaned with hot water under pressure. Superficial samples from conveyor belts (cleaned or not cleaned) were collected at three different times during operation (T1, after the preoperational cleaning [5 a.m.]; T2, after the first work shift [4 p.m.]; and T3, after the second work shift [1:30 a.m.]) in a poultry meat processing facility, and the samples were subjected to mesophilic and enterobacterial counts. For Enterobacteriaceae, no significant differences were observed between the conveyor belts, independent of the time of sampling or the cleaning process. No significant differences were observed between the counts of mesophilic bacteria at the distinct times of sampling on the conveyor belt that had not been subjected to continuous cleaning with water at 45°C. When comparing similar periods of sampling, no significant differences were observed between the mesophilic counts obtained from the conveyor belts that were or were not subjected to continuous cleaning with water at 45°C. Continuous cleaning with water did not significantly reduce microorganism counts, suggesting the possibility of discarding this procedure in chicken processing.

Selective sensing of adenosine monophosphate (AMP) over adenosine diphosphate (ADP), adenosine triphosphate (ATP), and inorganic phosphates with zinc(II)-dipicolylamine-containing gold nanoparticles

2021 ◽  
Author(s):  
Lena Reinke ◽  
Marcus Koch ◽  
Christine Müller-Renno ◽  
Stefan Kubik
Keyword(s):  
Gold Nanoparticles ◽  
Adenosine Triphosphate ◽  
Triethylene Glycol ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Mixed Monolayer ◽  
Inorganic Phosphates

Mixed monolayer-protected gold nanoparticles containing surface-bound triethylene glycol and dipicolylamine groups aggregated in water/methanol, 1:2 (v/v) in the presence of nucleotides, if the solution also contained zinc(II) nitrate to convert...

scholarly journals ON THE LOCALIZATION OF SOME PHOSPHATASES IN THREE DIFFERENT SEGMENTS OF THE PROXIMAL TUBULES IN THE RAT KIDNEY

1967 ◽  
Vol 15 (8) ◽  
pp. 456-469 ◽  
Author(s):  
N. O. JACOBSEN ◽  
F. JØRGENSEN ◽  
Å. C. THOMSEN
Keyword(s):  
Adenosine Triphosphate ◽  
Rat Kidney ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Proximal Tubules ◽  
Reaction Pattern ◽  
Cytoplasmic Bodies ◽  
Acid And Alkaline Phosphatase ◽  
Convoluted Tubules

The distribution of several phosphatases in three segments of the proximal tubules was studied in frozen sections of glutaraldehyde-fixed rat kidneys. Two segments of the convoluted tubules were identified by in vivo injection of trypan blue. By increasing the concentration of adenosine triphosphate to 3 mM in the Wachstein and Meisel ATPase medium, a clear segmental differentiation in the reaction pattern of the brush border, cytoplasmic bodies and basal infoldings of the proximal tubules was obtained. The specificity of the reaction was investigated by substituting adenosine diphosphate, adenosine monophosphate or β-glycerophosphate for adenosine triphosphate in the incubation medium and by employing cyanide or fluoride as inhibitors. The reaction pattern was also compared with the localization of acid and alkaline phosphatase activities. In addition, the distribution of glucose 6-phosphatase activity was studied which showed differences in the three segments of the proximal tubules.

Isolated flagellar apparatus of Chlamydomonas: characterization of forward swimming and alteration of waveform and reversal of motion by calcium ions in vitro

1978 ◽  
Vol 33 (1) ◽  
pp. 235-253 ◽  
Author(s):  
J.S. Hyams ◽  
G.G. Borisy
Keyword(s):  
Calcium Ions ◽  
Beat Frequency ◽  
Flagellar Apparatus ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Living Cells ◽  
Exogenous Calcium ◽  
Ph Range ◽  
Relationship Of

The control of flagellar activity in the biflagellate green alga, Chlamydomonas reinhardtii was investigated by the in vitro reactivation of the isolated flagellar apparatus (the 2 flagella attached to their respective basal bodies plus accessory structures). The waveform and beat frequency of the isolated apparatus in the presence of 1 mM adenosine triphophate (ATP) were comparable to those recorded for living cells. Equimolar concentrations of adenosine diphosphate (ADP) could be substituted for ATP with little change in beat frequency and no apparent change in waveform, suggesting that the latter is converted to ATP by axonemal adenylate kinase. No reactivation occurred in adenosine monophosphate (AMP). But frequencies in cytidine, guanosine and uridine triphosphates (CTP, GTP and UTP) were approximately 10% that obtained in ATP. Reactivation was optimal over a broad pH range between pH 6.4 and pH 8.9 in both APT and ADP. Isolated flagellar apparatus could be induced to change from forward to reverse motion in vitro by manipulation of exogenous calcium ions. The 2 types of motion were directly comparable to recorded responses of living cells. Forward swimming occurred at levels of calcium below 10(−6)M, the isolated apparatus changing to backward motion above this level. Motility was inhibited at concentrations above 10(−3)M. The threshold for reversal of motion by calcium was lowered to 10(−7)M when the flagellar membranes were solubilized with detergent, indicating that the flagellar membranes are involved in the regulaion of the level of calcium within the axoneme. The reversal of motion by calcium was itself freely reversible. The relationship of these observations to the known tactic responses of Chlamydomonas is discussed.

scholarly journals Crowding within synaptic junctions influence the degradation of adenoside nucleotides by CD39 and CD73 ectonucleotidases

2021 ◽  
Author(s):  
Hadi Rahmaninejad ◽  
Tom Pace ◽  
Peter Kekenes-Huskey
Keyword(s):  
Electrostatic Interactions ◽  
Configurational Entropy ◽  
Reaction Diffusion ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Surprising Result ◽  
Surface Charges ◽  
Association Rate ◽  
Synaptic Junction ◽  
Reaction Diffusion Model

Synapsed cells can communicate using exocytosed nucleotides like adenosine triphosphate (ATP). Ectonucleotidases localized to a synaptic junction degradesuch nucleotides into metabolites like adenosine monophosphate (AMP) or adenosine, oftentimes in a sequential manner. CD39 and CD73 are a representativeset of coupled ectonucleotidases, where CD39 first converts ATP and adenosine diphosphate (ADP) into AMP, after which the AMP product is dephosphorylated into adenosine by CD73. Hence, CD39/CD73 help shape cellular responses to extracellular ATP. In a previous study [1] we demonstrated that the rates of coupled CD39/CD73 activity within synapse-like junctions are strongly controlled by the enzymes' co-localization, their surface charge densities, and the electrostatic potential of the surrounding cell membranes. In this study, we demonstrate that crowders within a synaptic junction, which can include globular proteins like cytokines and membrane-bound proteins, impact coupled CD39/CD73 electronucleotidase activity and in turn, the availability of intrasynapse ATP. Specifically, we simulated a spatially-explicit, reaction-diffusion model for the coupled conversion of ATP -> AMP and AMP -> adenosine in a model synaptic junction with crowders via the finite element method. Our modeling results suggest that the association rate for ATP to CD39 is strongly influenced by the density of intrasynaptic protein crowders, as increasing crowder density suppressed ATP association kinetics. Much of this suppression can be rationalized based on a loss of configurational entropy. The surface charges of crowders can further influence the association rate, with the surprising result that favorable crowder/nucleotide electrostatic interactions can yield CD39 association rates that are faster than crowder-free configurations. However, attractive crowder/nucleotide interactions decrease the rate and efficiency of adenosine production, which in turn increases the availability of ATP and AMP within the synapse relative to crowder-free configurations. These findings highlight how CD39/CD73 ectonucleotidase activity, electrostatics and crowding within synapses influence the availability of nucleotides for intercellular communication.

scholarly journals Studies on Human Erythrocyte Nucleotide Metabolism. II. Nonspherocytic Hemolytic Anemia, High Red Cell ATP, and Ribosephosphate Pyrophosphokinase (RPK, E.C. 2.7.6.1) Deficiency

Blood ◽  
1972 ◽  
Vol 39 (5) ◽  
pp. 674-684 ◽  
Author(s):  
William N. Valentine ◽  
Helen M. Anderson ◽  
Donald E. Paglia ◽  
Ernst R. Jaffé ◽  
Patricia N. Konrad ◽  
...  
Keyword(s):  
Hemolytic Anemia ◽  
Reduced Glutathione ◽  
Adenine Nucleotides ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Blood Film ◽  
Nucleotide Metabolism ◽  
Glutathione Metabolism ◽  
Final Decision ◽  
Blood Samples

Abstract A 29-yr-old black woman was found to have a long-standing, nonspherocytic hemolytic disorder associated with a marked reduction in the activity of erythrocyte ribosephosphate pyrophosphokinase (RPK, PRPP synthetase, E.C. 2.7.6.1). Although the patient’s erythrocytes had about 50% of the average RPK activity of normal mature human erythrocytes, this level represented only about 20-30% of the activity in comparable reticulocyte-rich blood samples from patients with other types of hemolytic anemias. The concentrations of adenosine triphosphate adenosine diphosphate, adenosine monophosphate and, therefore, of total adenine nucleotides in her erythrocytes were markedly increased, even well above the levels in extracts of comparable reticulocyte-rich blood samples. ATPase activity was increased three- to fourfold, consistent with the reticulocytosis. Adenylate kinase and adenine phosphoribosyltransferase activities were normal. The activities of all enzymes of the Embden-Meyerhof and hexose monophosphate shunt pathways and enzymes related to glutathione metabolism were normal or increased, consistent with the reticulocytosis. The concentrations of glycolytic intermediates, other than adenine nucleotides, were normal. The conversion of glucose, adenosine, and inosine to lactate was normal or increased. Autohemolysis was of the Dacie Type II. The concentrations of erythrocyte-reduced glutathione were high normal or elevated. The stained blood film showed a striking degree of basophilic stippling of the erythrocytes. Studies of the erythrocytes of the patient’s only known relative, a son, have failed to reveal any hematologic or enzymatic abnormalities. A direct causal relationship between RPK deficiency, high ATP concentrations, and nonspherocytic hemolytic anemia could not be derived from data now available. The final decision as to whether the deficiency is primary and causative or is an epiphenomenon requires investigation of additional cases.

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