Bacteriocine typing of Proteus.

Abstract

SYNOPSIS A method of typing isolates of Proteus mirabilis and Proteus vulgaris is described based on the sensitivity of the organisms to bacteriocine. Twelve standard proteocine producing strains were selected from a large number of isolates tested, and from these liquid proteocine preparations were prepared. The sensitivities of 1805 isolates to these 12 preparations were then determined and none was found to be untypable. From the results a bacteriocine typing system has been developed.Bacteriocine typing has been shown to be successful in the characterization of specific strains of several genera of Gram-negative bacilli. Such typing enabled Abbott and Shannon (1958), Abbott and Graham (1961), and Gillies (1964) to study outbreaks of dysentery caused by Shigella sonnei. Likewise a detailed study of the bacteriocines (pyocines) produced by Pseudomonas aeruginosa led to typing schemes based on pyocine production (Wahba, 1963;Darrell and Wahba, 1964;Gillies and Govan, 1966). Linton (1960) described a method of colicine typing of strains of Escherichia coli. However, the production of bacteriocines (proteocines) by members of the genus Proteus has been little studied. An initial investigation into the typing of strains of Proteus by this method was unsatisfactory as only three proteocine types were discovered (Cradock-Watson, 1965 ing. Before use, 12 ml amounts of melted medium were distributed into sterile 9 cm diameter plastic Petri dishes, and the plates were dried in the incubator at 37°C for 2 hours. SOURCE OF STRAINSFive hundred and sixty-eight Proteus strains were obtained from clinical specimens from hospital patients during a period of nine months. The majority of organisms were isolated from urine and smaller numbers of pus, nasal, and wound swabs. Duplicate isolates from the same patients were avoided. BIOCHEMICAL IDENTIFICATIONThe conversion of phenylalanine to phenylpyruvic acid and the hydrolysis of urea on Christensen's medium were used as criteria to place non-lactosefermenting Gram-negative bacilli in the genus Proteus. Proteus mirabilis and Proteus vulgaris were identified on the basis of indole and H2S production, decarboxylation of ornithine, and fermentation of maltose. It was found that 59% were P. mirabilis and 41 % P. vulgaris. PRODUCTION OF PROTEOCINEFor production of proteocines, isolates are inoculated into 5 ml amounts of PP3 broth and incubated at 25°C. After 18 hours this culture is added to 50 ml of pre-heated (25°C) PP3 broth and incubated with orbital shaking at 25°C. After one hour mitomycin C (55 ,ug) is added to each culture to give a final concentration of 1 Htg mitomycin C per ml and the incubation is continued for a further 24 hours. The broth cultures are centrifuged at 3000 rev/min for 20 minutes, and the supernatant fluid is transferred to fresh sterile containers. Chloroform, 0 5 ml, is added to each flask, the contents of which are then thoroughly agitated for 5 minutes. The cultures are then 784 on 11 May 2018 by guest. Protected by copyright.

Pseudomonas aeruginosa: isolation from ocular tissues

“…aeruginosa, 15 (30.0%) were non-typable, 28 (56.0~o) were unclassifiable and the remaining 7 (14.0%) belonged to aeruginocin types A1 (3), B (2), F1 (1) and 14 (1). aeruginosa, 15 (30.0%) were non-typable, 28 (56.0~o) were unclassifiable and the remaining 7 (14.0%) belonged to aeruginocin types A1 (3), B (2), F1 (1) and 14 (1).…”

An evaluation of two methods of bacteriocine typing of organisms of the genus Proteus.

“…Cradock-Watson method reveals only nine types, Also, the large number of untypable isolates are a miscellaneous group, and non-typable organisms. differentiated, in this instance, by the Al-Jumaili A total of 48 sensitivity patterns has been demonmethod into 18 separate strains on the basis of their strated elsewhere (Al-Jumaili, 1975) using 1000 sensitivity patterns, On the other hand, where the Proteus isolates.…”

“…The method of typing was that described by Al-Jumaili in which the sensitivities of the unknown isolates to 12 standard proteocine preparations are determined (Al-Jumaili, 1975). All isolates had been previously investigated using the method of Cradock-Watson.…”

“…However, a higher proportion (75 %) of isolates tested by the Central Public Health Laboratory (Colindale) (CPHL) were found to be typable (Pitt, personal communication). A typing scheme based on the bacteriocine sensitivities of unknown isolates to standard proteocine preparations has now been developed and tested (Al-Jumaili, 1975) and the purpose of this work is to compare the epidemiological value of these two previously described systems. …”

Serious nosocomial infection caused by Morganella morganii and Proteus mirabilis in a cardiac surgery unit

“…mirabilis, however, is a well-known cause of clinically significant infection, and several outbreaks of nosocomial infection with this species have been described (7,8,20). Typing methods are well established and include 0-and H-serotyping (10, 13,16), proticine production and sensitivity typing (3,17), bacteriophage typing (11,12), and Dienes typing (10,12,21).…”