RAPID DIAGNOSIS OF ENTEROBACTERIACEAE

Abstract

The paper describes a number of tests for the rapid detection of glycosidases including α‐glucosidase, β‐glucosidase, β‐glucuronidase, β‐xylosidase and α‐fucosidase. The methods use heavy suspensions of viable but non‐multiplying bacteria in a buffered solution of a chromogenic substrate. The results of the tests are readable within 4 h. The application of these tests to a collection of 633 strains of Enterobacteriaceae and Vibrionaceae demonstrates that some of the tests may be valuable additions to the present tests available for the identification of bacteria belonging to these families, β‐glucuronidase activity was observed only in strains of the Escherichia‐Shigella group. 97 per cent of the Escherichia strains possessed β‐glucuronidase activity. β‐xylosidase activity was almost completely restricted to strains of the Klebsiella‐Enterobacter group in addition to Yersinia strains. None of the strains possessed α‐fucosidase activity.

A biosensor platform for rapid detection of E. coli in drinking water

“…No GUD activities were observed for the non-target bacteria and this finding is in the agreement with the previous research that "species of Klebsiella do not normally express GLUase activity" (Brenner et al 1993). Furthermore, studies have been performed on the GUD activities of the Enterobacteriaceae and E. coli and confirmed that GUD activity was mostly limited to (Kilian and Bülo 1976). In the Enterobacteriaceae genus, only 20% to 29% of the Salmonella isolates tested showed GUD positive activities (Kilian and Bülo 1976;Massenti et al 1980;Feng and Hartman 1982;Frampton and Restaino 1993).…”

“…The enzymatic detection of the indicator of fecal contamination E. coli via its marker enzymes GUD and the marker for coliforms, GAL, have been widely used (Kilian and Bülo 1976;Edberg and Kontnick 1986;Berg and Fiksdal 1988;Rice et al 1990;Hattenberger et al 2001). Considering that E. coli is employed as an indicative microorganism of wastewater and sewage contamination, the GUD-based assays and rapid tests are important in environmental monitoring where test simplicity and speed coupled with high sensitivity are critical features.…”

“…Although this bacterial enzyme was discovered first in E. coli, its relative specificity for identifying this microorganism was not apparent until Kilian and Bulow (1976) surveyed the Enterobacteriaceae and reported that glucuronidase activity was mostly limited to E. coli (Kilian and Bülo 1976). The prevalence of this enzyme and its utility in the detection of E. coli in water were later reviewed by Hartman (1989) (Feng and Hartman 1982).…”

“…GUD-positive reactions were observed in 94-97% of the E. coli isolates tested (Kilian and Bülo 1976;Feng and Hartman 1982;Edberg and Kontnick 1986), while Chang et al (1989) found a higher proportion of GUD negative E. coli (a median of 15% from E. coli isolated from human fecal samples) (Chang et al 1989). In contrast, GUD activity is less common in other Enterobacteriaceae genus, such as Shigella (44 to 58%), Salmonella (20 to 29%) and Yersinia strains and in Flavobacteria (Kilian and Bülo 1976;Feng and Hartman 1982;Hartman 1989;Frampton and Restaino 1993).…”

“…In contrast, GUD activity is less common in other Enterobacteriaceae genus, such as Shigella (44 to 58%), Salmonella (20 to 29%) and Yersinia strains and in Flavobacteria (Kilian and Bülo 1976;Feng and Hartman 1982;Hartman 1989;Frampton and Restaino 1993). GAL catalyzes the breakdown of lactose into galactose and glucose and has been used mostly for enumerating the coliform group within the Enterobacteriaceae family.…”