Submitted to: Applied and Environmental Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/20/2003
Publication Date: 1/20/2004
Citation: BRANDL, M., HAXO, A.F., BATES, A.H., MANDRELL, R.E. 2004. COMPARISON OF SURVIVAL OF CAMPYLOBACTER JEJUNI IN THE PHYLLOSPHERE WITH THAT IN THE RHIZOSPHERE OF SPINACH AND RADISH PLANTS. APPLIED AND ENVIRONMENTAL MICROBIOLOGY. 70:1182-1189. Interpretive Summary: Although campylobacteriosis is often linked to consumption of meat products, Campylobacter spp. has been isolated from produce and caused outbreaks linked to produce. Our results indicate that C. jeuni survived on plants at 10º C for many weeks. The presence of tissue damage and soil enhanced its survival on leaves, but its highest persistence was detected on radish roots and in the spinach rhizosphere, which comprises soil. The enhanced survival of C. jejuni in soil and in the rhizosphere may be a significant factor in its contamination cycle in the environment, and may be associated with the sporadic C. jejuni incidence and campylobacteriosis outbreaks linked to produce.
Technical Abstract: Campylobacter jejuni has been isolated previously from market produce and has caused outbreaks linked to produce. We have tested the ability of this human pathogen to utilize organic compounds that are present in leaf and root exudates, and to survive in the plant environment under various conditions. Carbon utilization profiles revealed that C. jejuni can utilize many organic acids and amino acids available on leaves and roots. Despite the presence of suitable substrates in the phyllosphere and the rhizosphere, C. jejuni was unable to grow on lettuce and spinach leaves, and spinach and radish roots of plants incubated at 33ºC, a temperature that is conducive to its growth in vitro. However, C. jejuni was cultured from radish roots and from the spinach rhizosphere for at least 23 and 28 days, respectively, at 10ºC. This enteric pathogen persisted also in the rhizosphere of spinach for prolonged periods of time at 16ºC, a temperature at which many cool season-crops are grown. The decline rate constant of C. jejuni in the spinach and radish rhizosphere, was 10- and 6-fold lower than on healthy spinach leaves, respectively, at 10ºC. The enhanced survival of C. jejuni in soil and in the rhizosphere may be a significant factor in its contamination cycle in the environment, and may be associated with the sporadic C. jejuni incidence and campylobacteriosis outbreaks linked to produce.