Biomedical subjects

O Markovic

Publications and source records attributed to O Markovic.

30 records · Page 2Linked to original sources

PubMed1981

Phylogenetic significance of protein and nucleotide content in yeasts.

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Amino Acids↗

PubMed1980

[Effects of molecular parameters of galacturonan substrate on the activity of a polygalacturonase from tomatoes].

The activity of a major form of the tomato polygalacturonase (EC 3.2.1.15) depends of the origin of the galacturonan substrates (apple, citrus) as well as upon the molecular mass, the degree of esterification and the distribution of the ester methoxyl groups. Optimal substrates are citrus pectic acids with a degree of esterification < 1% and a molecular mass corresponding to a viscosity number [eta] = 90 ml/g galacturonan. In the [eta] range from 16 to 474 ml/g, the Km values decrease to constant amount of 15.6 mM galacturonic acid units, which corresponds to 0.27% galacturonan. In a statistical distribution of the ester methoxyl groups, the activity reaches zero in the range of the degree of esterification from 80 to 90%. Enzymatically de-esterified pectins with a degree of esterification < 32% and a block-like distribution of the ester methoxyl groups behave as comparable pectic acids. In summary, there is a good agreement between these enzymesubstrate interactions and those of endopolygalacturonases from Aspergillus spec. Differentiations manifested themselves only in the transition range between macromolecular galacturonan substrates and oligomeric substrates below the established critical molecular mass.

Glycoside Hydrolases↗

PubMed1977

Enzyme kinetics in single cells: concept and model.

We describe a technique whereby it is possible to measure enzyme activity in a singel cell. The model chosen involved the measurement of myeloperoxidase activity in a polymorphonuclear neutrophil leukocyte. Details of the apparatus are described. The experiments necessary to optimize the reaction conditions are summarized. The nature of the phases of the reaction are described. The technique appears to have further application in measurement of the activities of other enzymes in leukocytes or other cells.

Densitometry↗

PubMed1977