The paracolon group of bacteria

Abstract

IN the routine bacteriological examination of faxes in Egypt, one frequently encounters coliform organisms giving acid and gas in glucose and rnannite and no change in sucrose or lactose in 24-48 hours, yet not agglutinating with paratyphoid sera. Some workers have described similar organisms as inagglutinable paratyphoid, others as paracolon bacilli ; the latter t , e m is employed in this paper. Literature.Gilbert and Lion (1893) described a group of coliform organisms found in the stools of dysentery patients which they termed paracolon bacilli. They were non-lactose fermenters (length of incubation not stated) and produced acid and gas in other test substances. They varied &s regards indo1 production and motility.Gyorgy (1920) studied forty-seven strains which he isolated from the stools of typhoid, paratyphoid and dysentery convalescents and from healthy normal persons. None fermented lactose and the majority failed to ferment sucrose but produced acid and gas in glucose, maltose, mannitol, xylose, rhamnose and dulcitol. Inositol was fermented only by two sucrosefermenting strains. After fourteen days litmus milk was turned acid or alkaline.Trawihki (1924) studied ninetyone strains of paratyphoid B-like organisms isolated from fzces, eighteen from healthy persons, the remainder from cases of enterica or dysentery. He records the following reactions (length of incubation not stated).All fermented glucose, mannitol, arabinose and, excepting a few, maltose, with the production of acid and gas. They differed in reaction on xylose and dulcitol. All formed indol, the majority in 24-48 hours. In litmus milk, after three weeks, most of them gave acid and a few alkali. According to their biochemical reactions he placed them in four groups and prepared an agglutinating serum in rabbits against a representative of each. Each serum agglutinated all the members of its own group to the same titre as its homologous organism ; apparently the sera were not tried against the other groups.Dudgeon (1926), in a paper on the intestinal flora under normal and abnormal conditions, mentions a group of " slow-lactose-fermenting bacilli which have been mistaken for the paratyphoid group although the indol test readily distinguishes them."Fothergill (1929), in America, investigated a group of thirty-two nonlactose-fermenting coliforms isolated from the feces of infants suffering Nearly all produced indol within 24 hours. None were motile. Most of them were motile. 77 1905-06. Proc. Roy. SOC. B., lxwii. 399. 1919. J . Trop. Med., xv. 162. J . Trop. Med., xxxvi. 65. J . Inf. Dis., xlv. 393. Cntrbl. f. Bakt., Abt. I, Orig., lxxxiv. 321. J. Inf. DiS., xxiv. 114.

Antigenic Relationships of the Coliform Bacteria

“…Some correlation was found between fermentation and agglutination. Sandiford (1935) investigated 41 paracolon cultures isolated from dysenteric stools. All the strains produced acid and gas in glucose and nearly all formed indole.…”

“…The practice of assigning to the coliform group certain strains of organisms which fail to produce gas in lactose or in any other carbohydrate or do not ferment lactose, is not without precedent (Topley and Wilson (1937), Fothergill (1929), Sandiford (1935 and others). Stuart, Griffin and Baker (1938) found that several coliform strains isolated as anaerogenic, in the course of several months produced gas in lactose and that occasionally aerogenic cultures lost their ability to produce gas.…”

“…It is becoming increasingly evident from investigations on coliform organisms in general that if the paracolon group of organisms is to be classed with the coliform bacteria, the rapid production of acid and gas in lactose or even the fermentation of lactose is in the last analysis no longer a criterion of a coliform organism. We wish to emphasize, as have Sandiford (1935) and Dudgeon (1926), the importance of the indole test in differentiating slow or nonlactose-fermenting Escherichia, particularly from Salmonella.…”

“…As previously pointed out, we believe the number of cultures and antiserums used was sufficient to give an adequate picture of antigenic relationships in the paracolon group. Moreover, Sandiford (1935), working in Egypt, found that 13.3 per cent of 41 paracolon cultures isolated from pathologic feces agglutinated in 9 paracolon antiserums.…”