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D JONES

Publications and source records attributed to D JONES.

At least 19 recordsLinked to original sources
PubMed1964

CATALASE ACTIVITY OF TWO STREPTOCOCCUS FAECALIS STRAINS AND ITS ENHANCEMENT BY AEROBIOSIS AND ADDED CATIONS.

Jones, Dorothy (American Meat Institute Foundation, Chicago, Ill.), R. H. Deibel, and C. F. Niven, Jr. Catalase activity of two Streptococcus faecalis strains and its enhancement by aerobiosis and added cations. J. Bacteriol. 88:602-610. 1964.-The nature of catalase activity noted in two unusual Streptococcus faecalis strains was determined. Enzyme activity was lost slowly when cultures were maintained by daily transfer in test tubes of broth media. Loss of activity could be prevented by aerobic culture. Supplementation of the growth medium with ferric, manganese, and zinc ions, as well as aerobiosis, enhanced catalase activity. However, addition of these cations to cell suspensions or to cell-free extracts did not increase catalase activity. Although oxygen was observed to be one of the reaction end products, the catalase activity was not inhibited by cyanide or azide, and the iron-porphyrin coenzyme of classical catalase was not detected. The enzyme was purified 185-fold by precipitation with ammonium sulfate, followed by chromotography on a diethylaminoethyl cellulose column.

Aerobiosis↗
PubMed1963

Identity of Staphylococcus epidermidis.

Jones, Dorothy (American Meat Institute Foundation, Chicago, Ill.), R. H. Deibel, and C. F. Niven, Jr. Identity of Staphylococcus epidermidis. J. Bacteriol. 85:62-67. 1963.-The species Staphylococcus epidermidis is defined more precisely, and compared with other staphylococci. The physiological characteristics considered to be of primary import are: (i) ability to grow anaerobically in a defined complex medium with glucose or pyruvate as the energy source; (ii) inability to produce coagulase; (iii) ability to ferment serine as an energy source; (iv) the requirement for biotin and uracil (under anaerobic conditions) in a semisynthetic medium; and (v) inability to reduce nitrate beyond nitrite.

Coagulase↗
PubMed1951

A rapid slide plaque technic for bacteriophage assay.

1. A modified rapid plaque-counting procedure is described, whereby staphylococcal phage host-cell suspensions in agar are spread over constant areas on glass slides and are incubated in moist chambers. 2. Statistical analysis indicated a precision of +/-8.2 for means of sets of eight slides incubated at 37 degrees C. and +/-7.6 for means of sets of eight incubated at 28 degrees C. 3. With the staphylococcus system, a temperature of 28 degrees C. yielded significantly higher counts than at 37 degrees C. 4. Counts made after 4 hours may be used as an estimate of the final plaque count bearing in mind the fact that the yield at this time is significantly less than at 24 hours. 5. The data presented compared favorably with the results obtained by the plate method used by Hershey, and suggest that a greater precision may be obtained by this method-at least for the staph. K phage system.

Bacteriophages↗