Studies on the Respiratory Mechanism of the Streptococci

Relation of Certain Respiratory Enzymes to the Maximum Growth Temperatures of Bacteria

“…Indeed, boiling the bacterial suspensions and cooling before add-ing the test reagents increases both rapidity of appearance and intensity of color produced with this reagent. Farrell (1935) found that tincture of o-tolidine and an aqueous solution of 2,7 diamino-fluorene-hydrochloride were very sensitive reagents for determining the presence of peroxidase of streptococci. Callow (1926) used guaiac and benzidine for detecting this enzyme.…”

The Oxidation of Glycerol by Streptococcus faecalis

“…It has been reported that certain of the lactic acid bacteria are capable of utilizing glycerol only under aerobic conditions (Gunsalus and Sherman, 1943). Inasmuch as these organisms are devoid of cytochrome (Frei et al, 1934;Farrell, 1935) and are reported to produce hydrogen peroxide during respiration, the presence of a functional respiration has been questioned. It therefore became of some importance to determine the nature of the reactions involved in the utilization of glycerol by these forms.…”

The Production of Active Resting Cells of Streptococci

“…Methylene blue as a hydrogen acceptor for work with streptococci has been objected to on the basis of its toxicity toward this group of organisms (Farrell, 1935). It is true that a very low concentration of methylene blue is toxic to the growth of streptococci, especially in broth.…”