SUMMARY: Screening tests indicated that Gram positive bacteria are inhibited by long chain fatty acids. No inhibition was demonstrated with Gram negative bacteria. The minimum inhibitory concentrations (MIC) for a series of the fatty acids are presented. Growth curves in the presence of linolenic acid showed increases in lag phase duration and calcium addition reversed this effect, thus indicating the arbitrary nature of the MIC values. Bactericidal studies showed lauric acid to be the most active saturated fatty acid but the activity was less than that of the C18 unsaturated fatty acids. Oleic acid was more effective than elaidic acid. Calcium ions, cholesterol and ergocalciferol reversed the activities of lauric and linoleic acids but magnesium ions effectively counteracted lauric acid only. A physicochemical explanation for the relative activities has been attempted.

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Salmonella in eggs and egg products with fluorescent antibody. Appl. Microbiol. 12:447-450. 1964.-Organisms of the genus Salmonella are detected in eggs and egg products within 24 hr in the presence of Pseudomonadaceae and other Enterobacteriaceae by combining selective cultural methods with fluorescentantibody techniques. These techniques are specific for Salmonella when H antibodies are used. Absorption techniques are necessary before the 0 antibodies give specific reactions for Salmonella. No cross-reactions appear when H antiserum is used. Absorption and interference techniques indicate the test is specific for Salmonella. Salmonellosis is one of the important food-borne infections in the world today; the United States alone reported almost 19,000 cases in 1963 (U.S. Department of Health, Education, and Welfare, 1964). Conventional methods for the isolation and identification of Salmonella are tedious and time-consuming. The development of a rapid and accurate test would be an invaluable aid toward controlling these organisms in dried eggs and egg products. Coons et al. (1942) introduced the fluorescent-antibody (FA) technique and made possible a new and rapid serological method of detecting microorganisms. In principle, this technique is an immunological staining procedure which uses homologous antibody conjugated with suitable fluorochromes. FA technique is now a common tool in microbiology and has generally been proved satisfactory. Thomason, Cherry, and Moody (1957) applied this method for the detection of several serotypes of Salmonella in pure culture. Later, Thomason, Cherry, and Edwards (1959) found that the value of the method for the rapid detection of Salmonella in feces was impaired by nonspecific staining.

A.M. PATON A N D C.M.J. INNES. 1991. Procedures for inducing viable intracellular associations between the L-forms of Pseudomonas syringae pv. phaseolicola and French dwarf bean, Phaseolus vulgaris, are described. It is suggested that this model system is a basis for more general application.

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