EFFECT OF OXYRASE^TM ENZYME ON LISTERIA MONOCYTOGENES AND OTHER FACULTATIVE ANAEROBES¹

Abstract

The use of an oxygen-reducing membrane fraction to stimulate growth of some anaerobic bacteria has been reported. In this study, stimulated recovery of Escherichia coli 0157:H7. Salmonella typhimurium, Streptococcus faecalis, and heat-injured Listeria monocytogenes was achieved by using broth media supplemented with Oxyrase "' (membrane-bound enzyme system derived from E. coli). The Oxyrase" enzyme allowed rapid growth of these facultatively anaerobic organisms in a nonselective broth. The activity of Oxyrase"' in four different selective enrichment broths to support growth of L. monocytogenes also was evaluated. Among tested broths, FDA-approved Listeria Enrichment Broth containing Oxyrase'" was found to be substantially superior for facilitating the growth of L. monocytogenes. Oxyrase"' promoted a signijicantly greater number of L. monocytogenes than commonly used but nonspecific reducing agents, such as L-cysteine HCl and sodium thioglycolate.Thesejndings indicated that all organisms tested can be grown well in liquid media using the oxygen-consuming membrane fragments to achieve and maintain oxygen-limited conditions. The Oxyrase "' enzyme system has potential applications in some selective media and other diagnostic tests specified for rapid detection of these facultatively anaerobic pathogens.

GROWTH OF PATHOGENIC BACTERIA IN UNIVERSAL PREENRICHMENT BROTH SUPPLEMENTED WITH OXYRASETM AND FERRIOXAMINE E1

“…OxyraseTM enhances the growth of bacteria by removing oxygen and acting as a nutritional stimulator . It has the ability to stimulate the growth of the entire group of facultative anaerobic food pathogens, including Clostridium perfringens, Listeria monocytogenes, Salmonella spp., Campylobacter spp., E. coli 0 157: H7, and Yersinia enterocolitica during enrichment (Hoskins and Davidson 1988;Yu and Fung 1991;Fung 1992, 1994;and Phebus et al 1993). Excellent stimulation of growth for most strains of Arcobacter butzleri by OxyraseTM in a broth system was reported by Liu et al (1995).…”

“…OxyraseTM, a sterile membrane fraction of Escherichia coli, performs as an oxygen scavenger in the medium. The cytochrome-based electron-transport enzyme system present in the cytoplasmic membrane of E. coli results in the reduction of oxygen to water (Yu and Fung 1991). OxyraseTM enhances the growth of bacteria by removing oxygen and acting as a nutritional stimulator .…”

Influence of Glucose Oxidase on the Growth of Escherichia Coli 0157:h7, Listeria Monocytogenes, and Salmonella Typhimurium in Universal Preenrichment Broth

“…1, 2 and 3). Other researchers have shown that OxyraseTM is most advantageous during the initial stages of enrichment (Phebus et al 1993;Yu and Fung 1991). During this period, GO provided the least growth stimulation.…”

“…More recently, microbial membrane fractions such as OxyraseTM have been used to remove dissolved oxygen from media (Yu and Fung 1991). Several researchers (Yu and Fung 1991;Phebus et al 1993) have reported that OxyraseTM enhances the growth of Listeria monocytogenes, Escherichia coli 0157:H7, and other facultatively anaerobic microorganisms. Jacob (1970) pointed out that pH changes may cause variations in Eh and, thus, pH and redox measurements should be taken simultaneously.…”

Evaluation of enrichment broths for their ability to recover heat‐injured Listeria monocytogenes

“…Studies have been done to improve recovery of sublethally injured L. monocytogenes cells by incorporating various chemicals into enrichment broths that either scavenge oxygen or degrade hydrogen peroxide (Busch and Donnelly 1992;Knabel et al 1990;Martin and Katz 1993;Yu and Fung 1991b). Hydrogen peroxide has been implicated as one of the major factors contributing to decreased survival and resuscitation of thermally stressed bacteria.…”