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Critical Reviews in Biochemistry and... 2015Determining the mechanisms of enzymatic regulation is central to the study of cellular metabolism. Regulation of enzyme activity via polymerization-mediated strategies... (Review)
Review
Determining the mechanisms of enzymatic regulation is central to the study of cellular metabolism. Regulation of enzyme activity via polymerization-mediated strategies has been shown to be widespread, and plays a vital role in mediating cellular homeostasis. In this review, we begin with an overview of the filamentation of CTP synthase, which forms filamentous structures termed cytoophidia. We then highlight other important examples of the phenomenon. Moreover, we discuss recent data relating to the regulation of enzyme activity by compartmentalization into cytoophidia. Finally, we hypothesize potential roles for enzyme filament formation in the regulation of metabolism, development and disease.
Topics: Animals; Carbon-Nitrogen Ligases; Eukaryota; Humans; Protein Multimerization
PubMed: 27098510
DOI: 10.3109/10409238.2016.1172555 -
Proceedings of the National Academy of... Sep 1980We have assayed carbonic anhydrase activity (carbonate dehydratase, carbonate hydro-lyase, EC 4.2.1.1) and bicarbonate permeability in suspensions of broken and intact...
We have assayed carbonic anhydrase activity (carbonate dehydratase, carbonate hydro-lyase, EC 4.2.1.1) and bicarbonate permeability in suspensions of broken and intact guinea pig mitochondria by monitoring the disappearance of C16O18O. We found significant activity in preparations from liver and skeletal muscle, but not in preparations from heart muscle, brain, and kidney. Intact mitochondria containing carbonic anhydrase produce a two-phase acceleration of the disappearance of the labeled CO2, which indicates that the enzyme is located in a region more accessible to CO2 than to HCO3-. Acetazolamide inhibits the enzyme activity instantly in broken mitochondria but only after a delay in intact mitochondria, indicating that the enzyme is in a region not immediately accessible to the inhibitor. Sonication of mitochondria containing carbonic anhydrase activity releases the enzyme, which remains in the supernatant after sedimentation of the submitochondrial particles. This shows that mitochondrial carbonic anhydrase is in the matrix compartment and not in, or bound to, the inner membrane. The activity of the enzyme increases markedly with increasing pH. The enzyme activity of intact mitochondria is greater than that of the broken mitochondria at the same pH of the suspending fluid, corresponding to an intramitochondrial pH that is 0.2-0.5 unit more alkaline.
Topics: Animals; Brain; Carbonic Anhydrases; Cell Fractionation; Guinea Pigs; Kidney; Liver; Mass Spectrometry; Mitochondria; Muscles; Myocardium
PubMed: 6776540
DOI: 10.1073/pnas.77.9.5562 -
Nutrients Dec 2021Zinc, an essential micronutrient in the human body, is a component in over 300 enzymes and participates in regulating enzymatic activity. Zinc metalloenzymes play a... (Review)
Review
Zinc, an essential micronutrient in the human body, is a component in over 300 enzymes and participates in regulating enzymatic activity. Zinc metalloenzymes play a crucial role in physiological processes including antioxidant, anti-inflammatory, and immune responses, as well as apoptosis. Aberrant enzyme activity can lead to various human diseases. In this review, we summarize zinc homeostasis, the roles of zinc in zinc metalloenzymes, the physiological processes of zinc metalloenzymes, and aberrant zinc metalloenzymes in human diseases. In addition, potential mechanisms of action are also discussed. This comprehensive understanding of the mechanisms of action of the regulatory functions of zinc in enzyme activity could inform novel zinc-micronutrient-supply strategies for the treatment of diseases.
Topics: Amyotrophic Lateral Sclerosis; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Asthma; Carbonic Anhydrases; Cardiovascular Diseases; Enzymes; Homeostasis; Humans; Immune System; Metalloproteins; Micronutrients; Pulmonary Disease, Chronic Obstructive; Trace Elements; Zinc
PubMed: 34960004
DOI: 10.3390/nu13124456 -
Redox Report : Communications in Free... Jul 2014This study was performed to investigate serum prolidase enzyme activity and oxidative stress in patients diagnosed with fibromyalgia (FM).
OBJECTIVE
This study was performed to investigate serum prolidase enzyme activity and oxidative stress in patients diagnosed with fibromyalgia (FM).
METHODS
The study population consisted of 40 patients with a previous diagnosis of FM and 30 healthy subjects. We measured serum prolidase enzyme activity, total antioxidant status (TAS), total oxidative status (TOS), oxidative stress index (OSI), and paraoxonase-1 (PON-1) levels.
RESULTS
On average, FM patients were diagnosed within 3.2 years of symptom onset, and patients had a mean of 14 tender points. There were no significant differences between patients and controls in age, body mass index, serum TAS, or PON-1 levels. However, patients with FM demonstrated higher serum prolidase activity, TOS, and OSI than the control group. Serum prolidase activity was positively correlated with serum TOS, OSI, and visual analog scale pain and fatigue scores. No correlation was found between serum prolidase activity and FM duration or the average number of tender points.
DISCUSSION
Our results demonstrate a previously unreported association between serum prolidase enzyme activity and FM. Increased prolidase activity may contribute to the pathogenesis of FM, and measuring serum prolidase enzyme activity may be a useful FM biomarker.
Topics: Adult; Antioxidants; Aryldialkylphosphatase; Dipeptidases; Female; Fibromyalgia; Humans; Male; Oxidation-Reduction; Oxidative Stress; Young Adult
PubMed: 24620938
DOI: 10.1179/1351000213Y.0000000079 -
Proceedings of the National Academy of... Apr 2017In this paper, we describe an approach to measuring enzyme activity based on the reconfiguration of complex emulsions. Changes in the morphology of these complex...
In this paper, we describe an approach to measuring enzyme activity based on the reconfiguration of complex emulsions. Changes in the morphology of these complex emulsions, driven by enzyme-responsive surfactants, modulate the transmission of light through a sample. Through this method we demonstrate how simple photodetector measurements may be used to monitor enzyme kinetics. This approach is validated by quantitative measurements of enzyme activity for three different classes of enzymes (amylase, lipase, and sulfatase), relying on two distinct mechanisms for coupling droplet morphology to enzyme activity (host-guest interactions with uncaging and molecular cleavage).
Topics: Amylases; Aspergillus; Candida; Emulsions; Kinetics; Lipase; Microfluidics; Optics and Photonics; Sulfatases; Surface-Active Agents
PubMed: 28348236
DOI: 10.1073/pnas.1618807114 -
Journal of Clinical Pathology Aug 1983There have been considerable advances in understanding the metabolic role of the endothelial lining cells of the blood vessels. Angiotensin-converting enzyme activity is... (Review)
Review
There have been considerable advances in understanding the metabolic role of the endothelial lining cells of the blood vessels. Angiotensin-converting enzyme activity is concentrated in these cells, especially those lining the pulmonary circulation. The enzyme exerts control over systemic vascular tone indirectly through the powerful pressor effect of angiotensin II. A number of therapeutic agents are now available which directly inhibit converting enzyme activity and thereby effect a reduction in blood pressure. Macrophages are the source of increased angiotensin-converting enzyme activity commonly found in association with active sarcoidosis. A better understanding of this phenomenon may give fresh insight into this puzzling condition. Pulmonary endothelial metabolism is affected by lung injury and it is likely that in this situation changing activities of serum angiotensin converting enzyme may indicate the extent of damage and the response to therapy. The full clinical significance of serum ACE measurements has yet to be established. However, raised activities have been reported in a number of other conditions and diabetes mellitus and hyperthyroidism are of particular current interest. The numerous methods and reference ranges described in the literature for the measurement of serum ACE activity require further assessment, and there is a clear need for an accepted reference method.
Topics: Adolescent; Adult; Aldosterone; Angiotensin-Converting Enzyme Inhibitors; Animals; Captopril; Dogs; Female; Humans; Hypertension; Lung Diseases; Macrophages; Male; Middle Aged; Peptidyl-Dipeptidase A; Rabbits; Renin; Sarcoidosis; Spectrophotometry
PubMed: 6308066
DOI: 10.1136/jcp.36.8.938 -
PloS One 2017Composted sewage sludge (CS) is considered a rich source of soil nutrients and significantly affects the physical, chemical, and biological characteristics of soil, but...
Composted sewage sludge (CS) is considered a rich source of soil nutrients and significantly affects the physical, chemical, and biological characteristics of soil, but its effect on specific enzyme activity in soil is disregarded. The present experiment examined the absolute and specific enzyme activity of the enzymes involved in carbon, nitrogen, and phosphorus cycles, the diversity of soil microbial functions, and soil community composition in a Fluventic Ustochrept under a maize-wheat rotation system in North China during 2012-2015. Application of CS led to increase in MBC and in its ratio to both total organic carbon (TOC) and microbial biomass nitrogen (MBN). Absolute enzyme activity, except that of phosphatase, increased in CS-treated soils, whereas specific activity of all the enzymes declined, especially at the highest dose of CS (45 t ha-1). The diversity of soil microbial community also increased in CS-treated soils, whereas its functional diversity declined at higher doses of CS owing to the lowered specific enzyme activity. These changes indicate that CS application induced the domination of microorganisms that are not metabolically active and those that use resources more efficiently, namely fungi. Redundancy analysis showed that fundamental alterations in soil enzyme activity depend on soil pH. Soil specific enzyme activity is affected more than absolute enzyme activity by changes in soil properties, especially soil microbial activity and composition of soil microflora (as judged by the following ratios: MBC/TOC, MBC/MBN, and TOC/LOC, that is labile organic carbon) through the Pearson Correlation Coefficient. Specific enzyme activity is thus a more accurate parameter than absolute enzyme activity for monitoring the effect of adding CS on the activities and structure of soil microbial community.
Topics: Bacteria; Bacterial Proteins; Carbon; Fungal Proteins; Fungi; Nitrogen; Phosphorus; Sewage; Soil; Soil Microbiology; Soil Pollutants
PubMed: 28545130
DOI: 10.1371/journal.pone.0177796 -
Medical Science Monitor : International... Oct 2015The aim of this study was to determine prolidase activity in conjunctival tissue and its relationship with pterygium.
BACKGROUND
The aim of this study was to determine prolidase activity in conjunctival tissue and its relationship with pterygium.
MATERIAL AND METHODS
Prolidase activity was measured in 23 pterygium and 25 healthy conjunctival tissues and the 2 groups were compared.
RESULTS
Prolidase enzyme activity could not be measured in either the healthy conjunctival or in pterygium tissues. The mean serum prolidase levels of the control and pterygium groups were 967.46±353.64 and 858.29±301.83, respectively. Statistically, there was no significant difference between the groups with regard to serum prolidase levels (p>0.05).
CONCLUSIONS
In conclusion, absence of prolidase activity in pterygium tissue indicates that there is no collagen turnover in this tissue. We may explain this finding with the elastin-rich structure of the conjunctiva.
Topics: Adult; Aged; Case-Control Studies; Collagen; Conjunctiva; Dipeptidases; Elastin; Female; Gene Expression Regulation, Enzymologic; Humans; Male; Middle Aged; Pterygium
PubMed: 26509313
DOI: 10.12659/msm.895050 -
International Journal of Oncology Jun 2012Esophageal cancer (EC) has a globally increasing incidence with poor curative treatment options and survival rates. Environmental and dietary factors have crucial roles...
Esophageal cancer (EC) has a globally increasing incidence with poor curative treatment options and survival rates. Environmental and dietary factors have crucial roles in esophageal carcinogenesis. Polymorphisms in the UGT genes, a superfamily of enzymes essential for the detoxification of carcinogens, may alter enzyme activity and subsequently may play a role in EC etiology. Rather than solely establishing differences in genotype distribution, we investigated whether functional polymorphisms in UGT genes that can predict enzyme activity in vivo, may influence EC risk. A case-control study including 351 Caucasian EC patients and 592 Caucasian controls was conducted and polymorphisms in seven UGT genes were determined, using the polymerase chain reaction. On the basis of allelic in vitro enzyme activity measurements, genotypes were categorized according to their predicted in vivo enzyme activity into high, medium and low categories. Predicted enzyme activity groups were combined and compared between patients and controls. The UGT1A1 and UGT1A8 predicted high enzyme activity genotypes were significantly more (OR=1.62; 95% CI, 1.02-2.56) and less frequent (OR=0.36; 95% CI, 0.15-0.84) among patients with esophageal squamous cell carcinoma (ESCC), respectively. High (OR=0.42; 95% CI, 0.22-0.84) and medium (OR=0.25; 95% CI, 0.12-0.52) activity UGT2B4 genotypes were significantly less often present in ESCC patients. No association was detected between UGT genotypes and esophageal adenocarcinoma (EAC) risk. Polymorphisms in UGT genes, resulting in altered enzyme activity genotypes, do not seem modifiers of EAC risk. However, the predicted high activity UGT1A1 genotype, associated with low serum levels of the antioxidant bilirubin, was associated with an increased ESCC risk. The UGT1A8 and UGT2B4 genotypes associated with decreased predicted enzyme activities, were significantly associated with an increased risk of ESCC, probably by a decreased detoxification of carcinogens.
Topics: Adenocarcinoma; Aged; Carcinoma, Squamous Cell; Case-Control Studies; Esophageal Neoplasms; Female; Genetic Association Studies; Genetic Predisposition to Disease; Glucuronosyltransferase; Haplotypes; Humans; Male; Middle Aged; Polymorphism, Genetic; Risk Factors
PubMed: 22367021
DOI: 10.3892/ijo.2012.1385 -
Sheng Wu Gong Cheng Xue Bao = Chinese... Apr 2017Laccases are enzymes belonging to the group of multi-copper oxidases. These enzymes are widely distributed in insects, plants, fungi and bacteria. In general, laccases... (Review)
Review
Laccases are enzymes belonging to the group of multi-copper oxidases. These enzymes are widely distributed in insects, plants, fungi and bacteria. In general, laccases can oxidize an exceptionally high number of substrates, so they have broad applications in textile, pulp, food and the degradation of lignin. However, low yield, low activity and thermo-instability of laccase in nature limit the application of laccase. High efficient heterologous expression of the protein is an effective way for solving this problem. Here, we summarize the research advances of heterologous expression of eukaryote-origin laccases. We focus on the overexpression of eukaryote-origin laccases using different expression system and the method for improving the production yield and enzyme activity in yeast cells. Information provided in this review would be helpful for researchers in the field.
Topics: Eukaryota; Industrial Microbiology; Laccase; Lignin; Microorganisms, Genetically-Modified; Yeasts
PubMed: 28920390
DOI: 10.13345/j.cjb.160352