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E WEISS

Publications and source records attributed to E WEISS.

At least 19 recordsLinked to original sources
PubMed1963

TRACHOMA AGENT: GLUCOSE UTILIZATION BY PURIFIED SUSPENSIONS.

Strain TE-55 of trachoma "virus" was extracted from infected chick-embryo yolk sacs, purified with the aid of diethylaminoethyl cellulose, and incubated with C(14)-glucose. Highly significant amounts of C140 were produced from carbon-i, but not from carbon-6 of glucose. This demonstrates independent carbohydrate metabolism in an extracellular environment by a microorganism of this group. siae than to true viruses.

Carbohydrate Metabolism↗
PubMed1962

Increased resistance to chloramphenicol in Rickettsia prowazekii with a note on failure to demonstrate genetic interaction among.

Weiss, Emilio (Naval Medical Research Institute, Bethesda, Md.) and Harry R. Dressler. Increased resistance to chloramphenicol in Rickettsia prowazekii with a note on failure to demonstrate genetic interaction among strains. J. Bacteriol. 83:409-414. 1962.-A further effort to produce genetically labeled Rickettsia prowazekii was made by serially passing the Madrid E strain in eggs in the presence of increasing concentrations of chloramphenicol. After 40 serial and 1 limit-dilution passages, a substrain, called C(r), was isolated, which appeared to be the result of a two-step change, each involving a twofold increase in resistance to the antibiotic. Chloramphenicol resistance was retained after 10 drugless egg passages. Cross-resistance to thiocymetin, but not to unrelated drugs, was shown. Several attempts were made to demonstrate genetic interaction, in eggs or entodermal cell cultures, among strains resistant to chloramphenicol, erythromycin, and p-aminobenzoic acid. They have not been successful.

4-Aminobenzoic Acid↗
PubMed1962

Properties of quinoxaline oxide-resistant Rickettsia typhi.

Weiss, Emilio (Naval Medical Research Institute, Bethesda, Md.) and Harry R. Dressler. Properties of quinoxaline oxide-resistant Rickettsia typhi. J. Bacteriol. 83:415-417. 1962.-An effort was made to apply to the Wilmington strain of Rickettsia typhi the observation that in certain strains of rickettsiae and viruses of the psittacosis group quinoxaline oxide resistance is easily obtained and is often accompanied by other changes. Resistance to quinoxaline oxide was obtained in R. typhi after 14 serial egg passages by a procedure somewhat more elaborate than the one used previously for R. prowazekii. Three limit-dilution isolates manifested an appreciable level of drug resistance (were unaffected by 0.5 mg/egg), but changes for unselected characteristics, such as "toxicity" for the mouse or growth or virulence for the chick embryo, were small and different in each case, and did not clearly resemble those obtained with the other microorganisms.

Animals↗