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E M Wise

Publications and source records attributed to E M Wise.

12 recordsLinked to original sources

Sulfonamide resistance mechanism in Escherichia coli: R plasmids can determine sulfonamide-resistant dihydropteroate synthases.

Several natural isolate E. coli strains highly resistant to sulfonamides and antibiotics are shown to contain a sulfonamide-resistant dihydropteroate synthase (2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine-diphosphate:4-aminobenzoate 2-amino-4-hydroxydihydropteridine-6-methenyltransferase, EC 2.5.1.15) in addition to the normal sensitive enzyme. The resistant dihydropteroate synthases examined are determined by an R plasmid and are smaller and less heat stable than the normal sulfonamide-sensitive enzyme. One synthase resistant to any sulfonamide tested, and to sulfanilic and arsanilic acids, was still inhibited by several non-sulfonamide analogs of p-aminobenzoate. Citrobacter and Klebsiella pneumoniae strains also show similar mechanisms of sulfonamide resistance.

Aminobenzoates↗

Adenosine 3':5'-cyclic monophosphate as a regulator of bacterial transformation.

Adenosine 3':5'-cyclic monophosphate added to exponentially growing cells of Hemophilus influenzae strain Rd increases competence for transformation 100- to 10,000-fold. Cyclic AMP added to near-stationary or stationary cells does not increase competence over the high level normally found in the early stationary phase.

Cyclic AMP↗

Teichoic acid hydrolase activity in soil bacteria (Bacillus subtilis-sporulation-phosphodiesterase-polyamines-concanavalin A).

Bacterial phosphodiesterases have been found that are capable of cleaving the backbone of teichoic acid. Such enzymes have not been reported previously. An aerobic, gram-negative, rod-shaped bacterium producing this activity was detected and isolated by autoradiography of soil suspensions growing on minimal medium containing (32)P-labeled Bacillus subtilis ATCC 6051 cell walls as the sole phosphorus source. Broken-cell preparations are capable of depolymerizing teichoic acids in media of low ionic strength at near-neutral pH values. An active teichoicase is also present in B. subtilis, ATCC 6051 (the Marburg strain), especially in sporulating cultures.

Autoradiography↗

Staphylococcus aureus H autolytic activity: general properties.

Staphylococcus aureus strain H has an autolytic activity which can be found in the cell wall but is most easily obtained from high-speed supernatant fractions of broken-cell preparations. As measured either turbidimetrically or radioactively, this activity is much greater on murein extracted from penicillin-treated cells than on murein extracted from normal cells.

Bacterial Proteins↗