ESEEM Investigations of the High pH and Low pH Forms of Chicken Liver Sulfite Oxidase

1998 ◽  
Vol 120 (44) ◽  
pp. 11263-11278 ◽  
Author(s):  
Arnold M. Raitsimring ◽  
Andrew Pacheco ◽  
John H. Enemark
Keyword(s):  
Sulfite Oxidase ◽  
Low Ph ◽  
Chicken Liver ◽  
High Ph

Direct Detection of the Proton-Containing Group Coordinated to Mo(V) in the High pH Form of Chicken Liver Sulfite Oxidase by Refocused Primary ESEEM Spectroscopy:  Structural and Mechanistic Implications

2000 ◽  
Vol 122 (22) ◽  
pp. 5294-5302 ◽  
Author(s):  
Andrei V. Astashkin ◽  
M. L. Mader ◽  
Andrew Pacheco ◽  
John H. Enemark ◽  
Arnold M. Raitsimring
Keyword(s):  
Direct Detection ◽  
Sulfite Oxidase ◽  
Chicken Liver ◽  
High Ph

Expression patterns of two carbonic anhydrase genes, Na+/K+-ATPase and V-type H+-ATPase, in the freshwater crayfish, Cherax quadricarinatus, exposed to low pH and high pH

2017 ◽  
Vol 65 (1) ◽  
pp. 50 ◽  
Author(s):  
Muhammad Yousuf Ali ◽  
Ana Pavasovic ◽  
Peter B. Mather ◽  
Peter J. Prentis
Keyword(s):  
Carbonic Anhydrase ◽  
Expression Patterns ◽  
Maximum Level ◽  
Low Ph ◽  
Freshwater Crayfish ◽  
Α Subunit ◽  
Cherax Quadricarinatus ◽  
High Ph ◽  
Internal Ph ◽  
Ph Conditions

Carbonic anhydrase (CA), Na+/K+-ATPase (NKA) and Vacuolar-type H+-ATPase (HAT) play vital roles in osmoregulation and pH balance in decapod crustaceans. As variable pH levels have a significant impact on the physiology of crustaceans, it is crucial to understand the mechanisms by which an animal maintains its internal pH. We examined expression patterns of cytoplasmic (CAc) and membrane-associated form (CAg) of CA, NKA α subunit and HAT subunit a in gills of freshwater crayfish, Cherax quadricarinatus, at three pH levels – 6.2, 7.2 (control) and 8.2 – over 24 h. Expression levels of CAc were significantly increased at low pH and decreased at high pH conditions 24 h after transfer. Expression increased at low pH after 12 h, and reached its maximum level by 24 h. CAg showed a significant increase in expression at 6 h after transfer at low pH. Expression of NKA significantly increased at 6 h after transfer to pH 6.2 and remained elevated for up to 24 h. Expression for HAT and NKA showed similar patterns, where expression significantly increased 6 h after transfer to low pH and remained significantly elevated throughout the experiment. Overall, CAc, CAg, NKA and HAT gene expression is induced at low pH conditions in freshwater crayfish.

scholarly journals A method for the preparation of low-pH dodecyl sulphate/polyacrylamide-gradient gels

1981 ◽  
Vol 193 (3) ◽  
pp. 1013-1015 ◽  
Author(s):  
G D Jones ◽  
M T Wilson ◽  
V M Darley-Usmar
Keyword(s):  
Cytochrome Oxidase ◽  
Low Ph ◽  
High Ph ◽  
Gel System

1. A low-pH lithium dodecyl sulphate/polyacrylamide-gradient slab-gel system, suitable for electrophoresis, is described, and the migration properties of standard proteins are compared on this and conventional high-pH gels. 2. Cytochrome oxidase may be partially resolved into its component polypeptides. The order of migration of these is, however, dependent on the pH of the gel system.

Enhanced performance of air-cathode two-chamber microbial fuel cells with high-pH anode and low-pH cathode

2010 ◽  
Vol 101 (10) ◽  
pp. 3514-3519 ◽  
Author(s):  
Li Zhuang ◽  
Shungui Zhou ◽  
Yongtao Li ◽  
Yong Yuan
Keyword(s):  
Fuel Cells ◽  
Microbial Fuel Cells ◽  
Low Ph ◽  
Air Cathode ◽  
High Ph

scholarly journals The pH-based ecological coherence of active canonical methanotrophs in paddy soils

2020 ◽  
Vol 17 (6) ◽  
pp. 1451-1462 ◽  
Author(s):  
Jun Zhao ◽  
Yuanfeng Cai ◽  
Zhongjun Jia
Keyword(s):  
Soil Ph ◽  
Rice Paddy ◽  
Low Ph ◽  
Paddy Soils ◽  
Paddy Fields ◽  
Type I ◽  
Type Ii ◽  
High Ph ◽  
Niche Specialization ◽  
Rice Paddy Soils

Abstract. Soil pH is considered one of the main determinants of the assembly of globally distributed microorganisms that catalyze the biogeochemical cycles of carbon (C) and nitrogen (N). However, direct evidence for niche specialization of microorganisms in association with soil pH is still lacking. Using methane-oxidizing bacteria (methanotrophs) as a model system of C cycling, we show that pH is potentially the key driving force selecting for canonical γ (type I) and α (type II) methanotrophs in rice paddy soils. DNA-based stable isotope probing (DNA-SIP) was combined with high-throughput sequencing to reveal the taxonomic identities of active methanotrophs in physiochemically contrasting soils from six different paddy fields across China. Following microcosm incubation amended with 13CH4, methane was primarily consumed by Methylocystis-affiliated type II methanotrophs in soils with a relatively low pH (5.44–6.10), whereas Methylobacter- or Methylosarcina-affiliated type I methanotrophs dominated methane consumption in soils with a high pH (7.02–8.02). Consumption of 13CH4 contributed 0.203 % to 1.25 % of soil organic C, but no significant difference was observed between high-pH and low-pH soils. The fertilization of ammonium nitrate resulted in no significant changes in the compositions of 13C-labeled methanotrophs in the soils, although significant inhibition of methane oxidation activity was consistently observed in low-pH soils. Mantel analysis further validated that soil pH, rather than other parameters tested, had significant correlation to the variation in active methanotrophic compositions across different rice paddy soils. These results suggest that soil pH might have played a pivotal role in mediating the niche differentiation of ecologically important aerobic methanotrophs in terrestrial ecosystems and imply the importance of such niche specialization in regulating methane emissions in paddy fields following increasingly intensified input of anthropogenic N fertilizers.

Growth of Listeria monocytogenes on Vacuum-packaged Beef

1990 ◽  
Vol 53 (9) ◽  
pp. 739-741 ◽  
Author(s):  
FREDERICK H. GRAU ◽  
PAUL B. VANDERLINDE
Keyword(s):  
Listeria Monocytogenes ◽  
Low Ph ◽  
Tissue Growth ◽  
Initial Population ◽  
Fatty Tissue ◽  
High Ph ◽  
Packaged Beef

Pieces of beef striploin (400 g) were inoculated with Listeria monocytogenes strain Murray B, vacuum packaged, and stored at either 0°C or 5.3°C. Growth of the organism on the beef depended on the temperature of storage, the pH of the lean, and the type of tissue. Growth was more rapid at 5.3°C than at 0°C, and faster on striploins of high pH (6.0–6.1) than on striploins of low pH (5.5–5.7). During storage, the population of L. monocytogenes was higher on fatty tissue than on lean principally because growth occurred earlier on the fat. When low pH striploins were held at 5.3°C, listeria grew from an initial count of 2–5×103 CFU/cm2 to 3×107 CFU/cm2 in 16 d on the fat, and in 20 d, to 106 CFU/cm2 on the lean and to 5×107 CFU/ml in the purge fluid. After storage at 0°C for 76 d, the populations reached were 106 CFU/cm2 on the fat, 104 CFU/cm2 on the lean, and 3×105 CFU/ml in the purge fluid. When high pH striploins were held at 0°C for 10 weeks, listeria grew from an initial population of 150–400 CFU/cm2 to just over 106 CFU/cm2 on the fat, 2×105 CFU/cm2 on the lean, and 4×106 CFU/ml in purge fluid.

Comparing metal leaching and toxicity from high pH, low pH, and high ammonia fly ash

Fuel ◽  
2007 ◽  
Vol 86 (10-11) ◽  
pp. 1623-1630 ◽  
Author(s):  
Anthony V. Palumbo ◽  
Jana R. Tarver ◽  
Lisa A. Fagan ◽  
Meghan S. McNeilly ◽  
Rose Ruther ◽  
...  
Keyword(s):  
Fly Ash ◽  
Low Ph ◽  
Metal Leaching ◽  
High Ph ◽  
High Ammonia

Electrochemical Behavior of Cu2+-Histidine Complexes on a Glassy Carbon Electrode

2011 ◽  
Vol 66 (3) ◽  
pp. 279-288 ◽  
Author(s):  
Yu-Ching Weng ◽  
Tian-Hao Cheng
Keyword(s):  
Glassy Carbon Electrode ◽  
Glassy Carbon ◽  
Electrochemical Behavior ◽  
Rotating Disk ◽  
Low Ph ◽  
Rotating Disk Electrode ◽  
Molar Ratio ◽  
Carbon Electrode ◽  
Oxidation Reactions ◽  
High Ph

The electrochemical behavior of Cu2+-L-histidine complexes on a glassy carbon electrode with various coordination environments in aqueous solution has been investigated. The Cu2+-histidine complexes are more easily reduced and oxidized at low pH (pH = 3 ~ 4) than at high pH (pH = 8 ~ 10). Both reduction and oxidation reactions of the Cu2+-histidine complexes are controlled by mass transfer at medium (pH = 5 ~ 7) and high pH (pH = 8 ~ 10) solutions. Even if the molar ratio of histidine to Cu2+ ions is as high as 100 : 1 at low pH of 4, the complexes are easily reduced to form Cu metal directly on the electrode surface. Glassy carbon rotating disk electrode experiments have shown that the electron transfer of the reduction reaction of the Cu2+-histidine complexes is close to 2.

Meat quality and chemical assessment of porcine longissimus dorsi within different muscle pH

2019 ◽  
Vol 59 (6) ◽  
pp. 1155 ◽  
Author(s):  
D. R. Kang ◽  
S. A. Belal ◽  
E. S. R. Cho ◽  
H. N. Kang ◽  
J. H. Jung ◽  
...  
Keyword(s):  
Amino Acids ◽  
Adenosine Diphosphate ◽  
Physicochemical Characteristics ◽  
Low Ph ◽  
Eating Quality ◽  
Longissimus Dorsi ◽  
Pork Quality ◽  
Isoleucine Leucine ◽  
High Ph ◽  
Longissimus Dorsi Muscle

This study was carried out to investigate the influence of pH on the Berkshire’s pork longissimus dorsi muscle, by comparing physicochemical characteristics in a high pH group (5.92 ± 0.02) and a low pH group (5.55 ± 0.03) on the basis of muscle pH24 h post-mortem. Fifteen pigs were assigned to each group (n = 15). The low pH group showed higher filter-paper fluid uptake, cooking loss and National Pork Producers Council marbling scores but did not significantly differ from the high pH group (P > 0.05). The low pH group also showed higher Commission International de l’Eclairage L* and b*, drip loss, and shearing forces were significantly different from the high pH group. However, Commission International de l’Eclairage meat colour value (a*) and National Pork Producers Council colour were higher in the high pH group. The content of glutamic acid, threonine, and serine amino acids associated with a good flavour was higher in the high pH group. Also, amino acids associated with a bitter or poor flavour, such as valine, isoleucine, leucine, tyrosine, and histidine, was higher in the high pH group as well. The taste of umami was significantly (P < 0.01) higher in the high pH group. Levels of the nucleotide compounds hypoxanthine and inosine tended to be higher (P < 0.05) in the high pH group, whereas adenosine diphosphate levels were increased in the low pH group (P < 0.05). It is concluded that pH of pork could be a good indicator of pork quality and related to factors influencing pork eating quality. As pH of pork is not only positively associated with physical traits of pork but also closely related to chemical traits of which higher free amino acids and nucleotides enhance pork quality.

Swelling of PVA/Chitosan/TiO2 Nanofibers Membrane in Different PH

2020 ◽  
Vol 990 ◽  
pp. 220-224
Author(s):  
Ari Dwi Nugraheni ◽  
Diki Purnawati ◽  
Ani Rohmatillah ◽  
Dian Nur Mahardika ◽  
Ahmad Kusumaatmaja
Keyword(s):  
Time Constant ◽  
Weight Ratio ◽  
Low Ph ◽  
Membrane Stability ◽  
Swelling Behavior ◽  
Cross Linking ◽  
High Ph ◽  
Chitosan Concentration ◽  
Nanofiber Membranes ◽  
Water Swelling

The nanofiber PVA/chitosan have been successfully fabricated by the addition of TiO2 or without TiO2. Nanofiber membranes of PVA/chitosan/TiO2 were fabricated with weight ratio of PVA/chitosan (w/w) 90/10, 85/15, and 80/20. Glutaraldehyde cross-linking was added to increase membrane stability in water. Swelling behavior was tested in three different pH to investigate the swelling behavior of nanofiber membranes of PVA/chitosan with and without TiO2. The result indicated that the addition of chitosan concentration would decrease the swelling index, and increase the time constant (τ). The swelling index will increase in high pH (pH 10.01) compare to low pH (pH 4.01).

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