The metabolism of tartaric acid by Penicillium charlesii

Klatt, K. P.; Rick, Paul D.; Gander, J.E.

doi:10.1016/0003-9861(69)90292-6

Cited by 5 publications

(1 citation statement)

References 27 publications

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“…Depending on the individual organism, L-(+)-tartrate is degraded by dehydratases (3,20,30,42) or dehydrogenases (9,27,29,35). Both types of enzymes have only been purified and characterized from Pseudomonas putida (20,29), and because of their instability, attempts to purify the corresponding enzymes from other microorganisms have been unsuccessful (9,24,30,42). Only recently, D-(-)-tartrate dehydratases, specific for the D-(-) stereoisomer, have been isolated from Rhodopseudomonas sphaeroides (39,41) and from two Pseudomonas strains (40).…”

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confidence: 99%

Purification and characterization of a bifunctional L-(+)-tartrate dehydrogenase-D-(+)-malate dehydrogenase (decarboxylating) from Rhodopseudomonas sphaeroides Y

Giffhorn¹,

Kuhn²

1983

J Bacteriol

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A bifunctional enzyme, L-(+)-tartrate dehydrogenase-D-(+)-malate dehydrogenase (decarboxylating) (EC 1.1.1.93 and EC 1.1.1..., respectively), was discovered in cells of Rhodopseudomonas sphaeroides Y, which accounts for the ability of this organism to grow on L-(+)-tartrate and D-(+)-malate. The enzyme was purified 110-fold to homogeneity with a yield of 51%. During the course of purification, including ion-exchange chromatography and preparative gel electrophoresis, both enzyme activities appeared to be in association. The ratio of their activities remained almost constant [1:10, L-(+)-tartrate dehydrogenase/D-(+)malate dehydrogenase (decarboxylating)] throughout all steps of purification. Analysis by polyacrylamide gel electrophoresis revealed the presence of a single protein band, the position of which was coincident with both L-(+)-tartrate dehydrogenase and D-(+)-malate dehydrogenase (decarboxylating) activities. The apparent molecular weight of the enzyme was determined to be 158,000 by gel filtration and 162,000 by ultracentrifugation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis yielded a single polypeptide chain with an estimated molecular weight of 38,500, indicating that the enzyme consisted of four subunits of identical size. The isoelectric point of the enzyme was between pH 5.0 and 5.2. The enzyme catalyzed the NAD-linked oxidation of L-(+)-tartrate as well as the oxidative decarboxylation of D-(+)-malate. For both reactions, the optimal pH was in a range from 8.4 to 9.0. The activation energy of the reaction (AlP) was 71.8 kJ/mol for L-(+)-tartrate and 54.6 kJ/mol for D-(+)-malate. NAD was required as a cosubstrate, and optimal activity depended on the presence of both

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