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M J JOHNSON

Publications and source records attributed to M J JOHNSON.

At least 19 recordsLinked to original sources

ENZYMATIC DEACYLATION OF S35-BENZYLPENICILLIN.

Pruess, David L. (University of Wisconsin, Madison), and Marvin J. Johnson. Enzymatic deacylation of S(35)-benzylpenicillin. J. Bacteriol. 90:380-383. 1965.-S(35)-benzylpenicillin, penicilloic acid, and penilloic acid were deacylated by cell suspensions of Escherichia coli and Micrococcus roseus. Both cultures deacylated penicillin most rapidly and penilloic acid least rapidly. The deacylase activity of M. roseus against penicilloic acid was cell-bound, probably requiring a metal ion for activity.

Acetone↗

Citric acid fermentation of sugars purified with chelating resin.

Noguchi, Yuichi (University of Wisconsin, Madison), and Marvin J. Johnson. Citric acid fermentation of sugars purified with chelating resin. J. Bacteriol. 82:538-541. 1961.-A new, independently isolated strain of Aspergillus niger capable of giving high yields of citric acid in submerged culture was found to show the same behavior toward iron, zinc, and manganese as a previously studied strain. Citric acid accumulation did not occur in the presence of manganese. Best citric acid production was obtained in the presence of limited amounts of iron and zinc. Use of a chelating ion exchange resin was found to be an excellent method of removing polyvalent metals from sugars, either for analytical purposes or for fermentation. Commercial glucose, after resin treatment, gave citric acid yields of more than 80% when supplemented with iron and zinc. Unpurified glucose was converted to citric acid in good yields by mycelium grown on resin-treated glucose.

Aspergillus↗