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J Konecny

Publications and source records attributed to J Konecny.

6 recordsLinked to original sources
PubMed1978

Alkalimetric microassay of cephalosporins.

Alkalimetric pH-stat titrations of cephalosporin C, cephacetril and their deacetyl derivatives using an acetyl esterase and beta-lactamase are described. The esterase was used to assay highly purified samples of cephalosporin C and cephacetril, and also to prepare analytically defined solutions of the deacetyl cephalosporins. Lactamase-catalyzed hydrolysis of the parent compounds was then found to generate exactly 2 equivalents of acid per mole; that of the deacetyl derivatives exactly 1 equivalent.

Acetylesterase↗
PubMed1977

Effects of carrier morphology and buffer diffusion on the expression of enzymatic activity.

A very stable esterase (EC 3.1.1.-), which hydrolyses ethyl acetate, cephalosporin C and other acetyl esters with a maximum turnover number of 3-10(2) s-1, was isolated from Bacillus subtilis ATCC 6633 and immobilized on two supports: controlled-pore glass and powdered brick, a representative of carriers having a wide pore-size distribution. Carrier morphology determines diffusion rates and the expression of activity. Rate-limiting mass transfer of buffer leads to apparent losses of activity, gross distortions of molecular pH vs. activity profiles and to apparent deviations from Michaelis-Menten kinetics.

Bacillus subtilis↗