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A method for growing Fusarium oxysporum, a mycelial fungus, and a technique for its use in mineral uptake studies have been described. Some general characteristics of the uptake process were determined. The fungus, grown for 54 hours, was found to take up as much K as 15 to 20 meq/100 g dry weight in 2 to 4 hours from a solution of 5 meq/l KCl. Approximately 3 to 5 meq of this uptake was readily removed by a CaCl2 rinse. The uptake was only slightly sensitive to pH over the range of 4 to 9. Below pH 4 uptake dropped rapidly. The age of the culture appeared to be the dominant factor in determining the rate of uptake. In contrast to other fungi, the presence of glucose during uptake was detrimental to K uptake. Conditions unfavorable for metabolic activity as low temperature, anaerobiosis, or the presence of DNP markedly reduced the uptake rate. Although the fungus took up Na from single salt solutions nearly as well K, the latter ion was much preferred in mixtures of the two ions. The organism showed no significant metabolic uptake of Ca or Cl. During uptake from KCl solutions, the organic acid content increased. The increase, chiefly in succinic acid and to a lesser extent in acetic and citric acids, amounted to about half the K uptake. The remainder of the K taken up was correlated with a roughly equivalent efflux of cellular Mg. [ABSTRACT FROM AUTHOR]

A method for the isolation of anaerobic bacteria from endodontic specimens under Continuous anaerobiosis is described. A mobile anaerobe unit supplies a gentle stream of oxygen-free gas over the tooth when the bacteriologic sample is taken. The paper-points are then, under oxygen-free gas, immediately transferred to prereduced, anaerobically sterilized roll tubes. The different isolated anaerobic bacteria are typed with biochemical tests, antibiotic susceptibility testing and gas chromatographic analysis of volatile fatty acids and alcohols. [ABSTRACT FROM AUTHOR]