On the Determination of Carbonic Anhydrase in Biological Material

1961 ◽  
Vol 13 (3) ◽  
pp. 416-417
Author(s):  
Å. Holmgård
Keyword(s):  
Carbonic Anhydrase ◽  
Biological Material

Determination of platinum in biological material by differential pulse polarography: Analysis in urine, plasma and tissue following sample combustion

1983 ◽  
Vol 48 (10) ◽  
pp. 2903-2908 ◽  
Author(s):  
Viktor Vrabec ◽  
Oldřich Vrána ◽  
Vladimír Kleinwächter
Keyword(s):  
Biological Material ◽  
Biological Fluid ◽  
Mercury Electrode ◽  
Differential Pulse ◽  
Differential Pulse Polarography ◽  
Linear Calibration ◽  
Catalytic Current ◽  
Pulse Polarography ◽  
Dropping Mercury Electrode

A method is described for determining total platinum content in urine, blood plasma and tissues of patients or experimental animals receiving cis-dichlorodiamineplatinum(II). The method is based on drying and combustion of the biological material in a muffle furnace. The product of the combustion is dissolved successively in aqua regia, hydrochloric acid and ethylenediamine. The resulting platinum-ethylenediamine complex yields a catalytic current at a dropping mercury electrode allowing to determine platinum by differential pulse polarography. Platinum levels of c. 50-1 000 ng per ml of the biological fluid or per 0.5 g of a tissue can readily be analyzed with a linear calibration.

scholarly journals THE DETERMINATION OF IODINE IN BIOLOGICAL MATERIAL

1935 ◽  
Vol 110 (1) ◽  
pp. 29-38
Author(s):  
Virginia Trevorrow ◽  
Gladys J. Fashena
Keyword(s):  
Biological Material

scholarly journals Polymorphisms in Brucella Carbonic anhydrase II mediate CO2 dependence and fitness in vivo

2019 ◽  
Author(s):  
JM García-Lobo ◽  
Y Ortiz ◽  
C González-Riancho ◽  
A Seoane ◽  
B Arellano-Reynoso ◽  
...  
Keyword(s):  
Carbonic Anhydrase ◽  
Primary Cultures ◽  
Low Frequency ◽  
Carbonic Anhydrase Ii ◽  
Carbonic Anhydrases ◽  
Significant Difference ◽  
Dependent Strain

AbstractSome Brucella isolates are known to require an increased concentration of CO2 for growth, especially in the case of primary cultures obtained directly from infected animals. Moreover, the different Brucella species and biovars show a characteristic pattern of CO2 requirement, and this trait has been included among the routine typing tests used for species and biovar differentiation. By comparing the differences in gene content among different CO2-dependent and CO2-independent Brucella strains we have confirmed that carbonic anhydrase II (CA II), is the enzyme responsible for this phenotype in all the Brucella strains tested. Brucella species contain two carbonic anhydrases of the β family, CA I and CA II; genetic polymorphisms exist for both of them in different isolates, but only those putatively affecting the activity of CA II correlate with the CO2 requirement of the corresponding isolate. Analysis of these polymorphisms does not allow the determination of CA I functionality, while the polymorphisms in CA II consist of small deletions that cause a frameshift that changes the C-terminus of the protein, probably affecting its dimerization status, essential for the activity.CO2-independent mutants arise easily in vitro, although with a low frequency ranging from 10−6 to 10−10 depending on the strain. These mutants carry compensatory mutations that produce a full length CA II. At the same time, no change was observed in the sequence coding for CA I. A competitive index assay designed to evaluate the fitness of a CO2-dependent strain compared to its corresponding CO2-independent strain revealed that while there is no significant difference when the bacteria are grown in culture plates, growth in vivo in a mouse model of infection provides a significant advantage to the CO2-dependent strain. This could explain why some Brucella isolates are CO2-dependent in primary isolation. The polymorphism described here also allows the in silico determination of the CO2 requirement status of any Brucella strain.

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