Cobalt Substituted Zinc Metalloenzymes

1973 ◽  
pp. 1-12 ◽  
Author(s):  
Bert L. Vallee
Keyword(s):  
Zinc Metalloenzymes

Zinc and Acrodermatitis Enteropathica

1980 ◽  
Vol 2 (3) ◽  
pp. 88-94
Keyword(s):  
Zinc Deficiency ◽  
Autosomal Recessive ◽  
Acid Metabolism ◽  
Autosomal Recessive Disease ◽  
Dna Polymerases ◽  
Clinical Manifestations ◽  
Acrodermatitis Enteropathica ◽  
Nucleic Acid Metabolism ◽  
Zinc Metalloenzymes ◽  
Rna And Dna

Mammalian zinc metalloenzymes include alkaline phosphatase. Zinc plays a crucial role in nucleic acid metabolism. RNA and DNA polymerases and thymidine kinase are zinc-dependent enzymes. Zinc deficiency in North America is most clearly seen in the disease acrodermatitis enteropathica. This is an autosomal recessive disease due to a zinc metabolic error—not well defined—which leads to zinc deficiency. Clinical manifestations include a rash around orifices, alopecia, and diarrhea. The laboratory can demonstrate hypozincemia and hypozincuria. Clinical and biochemical remission occurs with oral zinc administration.(R.H.R.)

scholarly journals Function and Mechanism of Zinc Metalloenzymes

2000 ◽  
Vol 130 (5) ◽  
pp. 1437S-1446S ◽  
Author(s):  
Keith A. McCall ◽  
Chih-chin Huang ◽  
Carol A. Fierke
Keyword(s):  
Zinc Metalloenzymes

Cyanobacterial carbonic anhydrases

2005 ◽  
Vol 83 (7) ◽  
pp. 721-734 ◽  
Author(s):  
Anthony K-C So ◽  
George S Espie
Keyword(s):  
Carbonic Anhydrase ◽  
Gene Families ◽  
Marine Cyanobacteria ◽  
Carbonic Anhydrases ◽  
Catalytic Function ◽  
Concentrating Mechanism ◽  
Number Distribution ◽  
Zinc Metalloenzymes

Carbonic anhydrases (CAs) are ubiquitous zinc metalloenzymes that catalyze the reversible dehydration of HCO3–. These enzymes are encoded by at least five distinct, evolutionarily unrelated gene families, four of which have been found among the cyanobacteria examined to date. However, the distribution and expression of these cyanobacterial α-, β-, γ-, and ∈-CAs and their homologues among species have not yet been investigated in great detail. In this study, the number, distribution, and catalytic function of known and putative CAs and CA-like proteins from a variety of freshwater and marine cyanobacteria are examined.Key words: carbonic anhydrase, carboxysome, CO2-concentrating mechanism, cyanobacteria, Prochlorococcus, Synechococcus, Synechocystis.

scholarly journals Indicators of zinc status at the population level: a review of the evidence

2008 ◽  
Vol 99 (S3) ◽  
pp. S14-S23 ◽  
Author(s):  
Rosalind S. Gibson ◽  
Sonja Y. Hess ◽  
Christine Hotz ◽  
Kenneth H. Brown
Keyword(s):  
Serum Zinc ◽  
Population Level ◽  
Molecular Techniques ◽  
Collaborative Group ◽  
Zinc Status ◽  
Turnover Rates ◽  
Functional Responses ◽  
Zinc Metalloenzymes ◽  
Zinc Concentrations ◽  
New Biomarkers

The role of zinc deficiency as an important cause of morbidity and impaired linear growth has prompted the need to identify indicators of population zinc status. Three indicators have been recommended – prevalence of zinc intakes below the estimated average requirement (EAR), percentage with low serum zinc concentrations, and percentage of children aged < 5 years who are stunted. This review outlines steps to estimate the prevalence of inadequate intakes, and confirm their validity based on the EARs set by International Zinc Nutrition Collaborative Group. Next, the appropriateness of serum zinc as a biochemical marker for population zinc status is confirmed by a summary of: (a) the response of serum zinc concentrations to zinc intakes; (b) usefulness of serum zinc concentrations to predict functional responses to zinc interventions; (c) relationship between initial serum zinc and change in serum zinc in response to interventions. Height- or length-for-age was chosen as the best functional outcome after considering the responses of growth, infectious diseases (diarrhoea, pneumonia), and developmental outcomes in zinc supplementation trials and correlation studies. The potential of other zinc biomarkers such as zinc concentrations in hair, cells, zinc-metalloenzymes, and zinc-binding proteins, such as metallothionein, is also discussed. Molecular techniques employing reverse transcriptase (RT)-polymerase chain reaction to measure mRNA in metallothionein and ZIP1 transporter hold promise, as do kinetic markers such as exchangeable zinc pools (EZP) and plasma zinc turnover rates. More research is needed to establish the validity, specificity, sensitivity, and feasibility of these new biomarkers, especially in community-settings.

scholarly journals Structural and Mutagenic Analysis of Metallo-β-Lactamase IMP-18

2016 ◽  
Vol 60 (9) ◽  
pp. 5521-5526 ◽  
Author(s):  
Takamitsu Furuyama ◽  
Haruka Nonomura ◽  
Yoshikazu Ishii ◽  
Nancy D. Hanson ◽  
Akiko Shimizu-Ibuka
Keyword(s):  
Crystal Structure ◽  
Active Site ◽  
Kinetic Properties ◽  
Amino Acid Residues ◽  
Content Type ◽  
Zinc Metalloenzymes ◽  
Order Of Magnitude ◽  
Sandwich Configuration ◽  
The Relationship ◽  
Loop Conformation

ABSTRACTIMP-type metallo-β-lactamases (MBLs) are exogenous zinc metalloenzymes that hydrolyze a broad range of β-lactams, including carbapenems. Here we report the crystal structure of IMP-18, an MBL cloned fromPseudomonas aeruginosa, at 2.0-Å resolution. The overall structure of IMP-18 resembles that of IMP-1, with an αβ/βα “folded sandwich” configuration, but the loop that covers the active site has a distinct conformation. The relationship between IMP-18's loop conformation and its kinetic properties was investigated by replacing the amino acid residues that can affect the loop conformation (Lys44, Thr50, and Ile69) in IMP-18 with those occupying the corresponding positions in the well-described enzyme IMP-1. The replacement of Thr50 with Pro considerably modified IMP-18's kinetic properties, specifically those pertaining to meropenem, with thekcat/Kmvalue increased by an order of magnitude. The results indicate that this is a key residue that defines the kinetic properties of IMP-type β-lactamases.

scholarly journals Aberrance of Zinc Metalloenzymes-Induced Human Diseases and Its Potential Mechanisms

Nutrients ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 4456
Author(s):  
Yunqi Cheng ◽  
Hongping Chen
Keyword(s):  
Enzyme Activity ◽  
Immune Responses ◽  
Enzymatic Activity ◽  
Mechanisms Of Action ◽  
Zinc Homeostasis ◽  
Human Diseases ◽  
Comprehensive Understanding ◽  
Physiological Processes ◽  
Zinc Metalloenzymes ◽  
Regulatory Functions

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.

Microanalytical System for Determination of Picogram Quantities of Metals in Metalloenzymes, as Illustrated with Zinc-containing Enzymes

1975 ◽  
Vol 21 (4) ◽  
pp. 591-594 ◽  
Author(s):  
Hiroshi Kawaguchi ◽  
David S Auld
Keyword(s):  
Emission Spectrometry ◽  
Woolly Monkey ◽  
Zinc Metalloenzymes ◽  
Exclusion Chromatography ◽  
Tumor Virus ◽  
Weight Protein ◽  
Low Molecular Weight Protein ◽  
Type C ◽  
Analytical System

Abstract Microwave-induced emission spectrometry combined with gel-exclusion chromatography provides a microanalytical system capable of precisely measuring 10-10 to 10-13 g of metal in microgram amounts of enzyme. Such sensitivity greatly exceeds that of other, more conventional methods. Metal quenching agents and low-molecular-weight protein contaminants were removed from the enzyme by Sephadex G-100 chromatography in microbore columns (0.3 x 25 cm). Droplet fractions were analyzed for zinc by the present method, for enzyme activity, and for protein content. With this analytical system we could demonstrate that stoichiometric amounts of zinc are present in the RNA-dependent DNA polymerase, the reverse transcriptase, from woolly monkey type C RNA tumor virus. The precision of the method for zinc was demonstrated by the coefficient of variation of 4.4% for 10 µg of zinc per liter. Validity and accuracy of the method were established by determining zinc in a series of zinc metalloenzymes of known metal content and stoichiometry.

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