English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Microbiological &search Establishment, Porton, Wiltshire SUMMARY: When young growing filaments or microcolonies of Bacillus anthrd were treated with specific bacteriophage, fragmentation of the filaments followed by complete disintegration of the microcolony were visible microscopically within 2-3 hr. Other Bacillus species were unaffected by the phage. This technique is a simple one for accelerating the identification of Bacillus anthracis. Bacillus anthracis may be distinguished from the closely related B. cereus by its susceptibility to a specific bacteriophage (McCloy, 1951). The usual tech- nique for testing a suspected strain with phage consists in spotting the un- diluted phage on a bacterial lawn on agar, and observing for lysis after incuba- tion overnight (McCloy, 1951; Brown & Cherry, 1955). It seemed that identi- fication could be accelerated by applying the phage to the bacteria at an earlier stage of their growth, and observing lysis microscopically. The experiments reported in this paper confirmed this prediction. METHODS AND RESU,L'I'S Bacteriophage. The bacteriophage used was a virulent mutant a ofsa tem- perate phage 1, derived from a Bacillus cereus strain W (McCloy, 1958). The phage was used undiluted at a titre of 1.5 x 1O1O particles/ml. The phage may be propagated on any strain of B. anthracis. dilution in broth of an overnight culture of Bacillus anthracis was incubated for 3 hr. at 37". The culture tube was held in EL Perspex drum rotating at about 2 rev./sec., inclined at 45' and fixed in a wooden box, the temperature inside which was controlled thermostatically. The drum was rotated by a low-power motor. The source of heat was a 100 W. electric light bulb placed beneath a metal reflector. To the resulting logarith- mic phase culture was added a phage in the proportion of lo9 particles/lO ml. culture, and incubation continued until clearing was complete, usually about 23 hr. after addition of the phage. The bacterial debris was centrifuged, and the supernatant liquid treated with 1 ml. chloroform. The lysate was left in contact with chloroform for 30 min. on the bench, and the chloroform then removed by suction. A sterility test was performed on the lysate, which was afterwards ready for use. Technique of the phage-lysis microtest. Light inocula of Bacillus anthracis

Rapid identification of Bacillus anthracis by Microscopical Observation of Bacteriophage Lysis631