The purpose of the present investigation was to demonstrate transformation in the genus Rhizobium, using strains of R. meliloti and R. trifolii as the test organisms. The initial work was directed towards an understanding of the metabolism of these organisms and the selection of stable mutants suitable for use in such a study. Five chloramphenicol-resistant strains of R. trifolii were obtained by a "Crystal Violet-tolerance" technique developed during the course of the present research. Suitably resistant strains of R. meliloti could not be isolated. Streptomycin resistance was subsequently selected for among the chloramphenicol-resistant strains.

The fundamental problem in the nutrition of any organism (animal, plant or microbe), according to Porter (1946), is the construction of a medium, or diet, of known composition which will permit optimum growth and reproduction. With bacteria this problem has led to the development of chemically defined or synthetic media, that is, media composed of known purified chemicals. The advantages of protein free synthetic media for biochemical study were appreciated early in the history of bacteriology.

It has been proposed within recent years that the neurotoxin of Clostridium botulinum might exert its effect in the animal body by interfering with the synthesis or release of acetylcholine at myoneural junctions. The object of this study was to determine whether or not botulinum toxin inhibits the bacterial acetylation of choline. No effect upon the synthesis or release of acetylcholine by Lactobacillus plantarum was demonstrated. It may be that the large toxin molecule is unable to penetrate the cell membrane. The apparent activity of a bacterial cell-free "extract" of the enzyme involved in the acetylation of choline indicates however the advisability of further work.

In a paper published in 1883 Ogston had this to say of the "micrococci": "Yet when the animal (injected with "micrococci" taken from a suppurative infection) is subjected to microscopic scrutiny, we find that at the seemingly unimportant injection site an enormous and appalling growth of deadly organisms, in numbers that would be but faintly computed by millions, while the blood which we would naturally have supposed to be richly inhabited, is so poorly provided with the organism that it is clear that the chemical intoxication by the ptomaine, not the vital injection of the germ, has been the cause of death".

At present there is neither a general scheme nor are there even well defined criteria which may be followed in placing an organism within the genus corynebacterium. Morphological and physiological studies to date have not provided a satisfactory solution. The literature is indicative of extensive serological investigations but is, on the whole, concerned with the type species C. diphtheriae. [...]

The purpose of this investigation was to study the biological and immunological properties of purified preparations of Staphylococcus pyogenes Wood 46 alpha toxin. The toxin was fractionated by carboxymethyl cellulose column chromatography and purified by a zinc-ethanol precipitation technique and the materials tested for functional antigenicity in rabbits. An attempt was made to contribute to the question of unity and diversity of biological activities associated with the alpha haemolysin of Staphylococcus pyogenes using the technique of zone electrophoresis on starch-gel.

In 1947 a mould was found growing as a contaminant on a Lowenstein's slope which had been inoculated with sputum for the isolation of Mycobacterium tuberculosis which was found to produce, in addition to an antibiotic probably identical with penicillin, a substance capable of neutralizing various bacterial exotoxins. (Diena, 1954, 1956; Murray, Denton, Stevenson and Diena, 1958). The mould was identified as Penicillium cyaneo-fulvum and the toxin neutralizing substance was designated noxiversin. Noxiversin was shown to possess, in addition to its antitoxic properties, some activity against influenza virus (Diena, 1956).

Bright's (1836) original observations on and description of acute glomerulonephritis have since been confirmed and expanded by a great many workers and it is now a generally accepted concept that acute glomerulonephritis represents a not uncommon complication of streptococcal infections of the upper respiratory tract.

Acute glomerulonephritis is now considered to be a nonsuppurative complication of an upper respiratory infection with haemolytic streptococci of Lancefield's Group A. It has also been shown by various investigators (Rammelkamp and Weaver, 1952; Manser and Wilson, 1952; Reed, 1953) that an attack of glomerulonephritis is much more likely to follow infections with Type 12 streptococci than with other serological types. [...]

No description available.