Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: MOLECULAR CHARACTERIZATION AND GASTROINTESTINAL TRACT ECOLOGY OF COMMENSAL HUMAN FOOD-BORNE BACTERIAL PATHOGENS IN THE CHICKEN

Location: Poultry Microbiological Safety Research

Title: Differential carbon source utilization by Campylobacter jejuni strain 11168 in response to growth temperature variation

Authors
item LINE, JOHN
item HIETT, KELLI
item GUARD, JEAN
item SEAL, BRUCE

Submitted to: Journal of Microbiological Methods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 18, 2009
Publication Date: February 1, 2010
Citation: Line, J.E., Hiett, K.L., Guard, J.Y., Seal, B.S. 2010. Differential carbon source utilization by Campylobacter jejuni strain 11168 in response to growth temperature variation. Journal of Microbiological Methods. 80:198-202.

Interpretive Summary: Campylobacter readily colonize the intestinal tracts of both human and avian species. While it mostly does not cause illness in birds, campylobacter remains the leading cause of bacterial gastroenteritis in humans. The association of campylobacter with poultry is well established as a primary route for human exposure. The difference in normal core body temperature between chickens (42°C) and humans (37°C) has been suggested to trigger potential colonization or virulence factors and, indeed, recent studies have demonstrated differential gene expression at the two temperatures. Campylobacter exhibit unique nutritional requirements and have been thought to only utilize amino acids and Kreb cycle intermediates as carbon sources for growth. We evaluated the ability of the genome-sequenced strain of Campylobacter jejuni 11168 to oxidize 190 different substrates as sole carbon sources at 37°C and 42°C using phenotype microarray technology. Results indicate that the expected amino acids, L-serine, L-aspartic acid, L-asparagine, L-proline and L-glutamic acid were utilized in addition to a number of organic acids. In general, oxidation of the substrates was greater at 42°C than at 37°C with a few exceptions. Interestingly, by employing the new method, we are able to report for the first time the utilization of a number of carbohydrates sources by this bacterium, including the triose, dihydroxyacetone; the hexose sugar, L-fucose; and the pentose sugars, D-xylose, D-ribose, L-lyxose, and D- and L-arabinose. The presence of genes possibly responsible for utilization of these carbohydrates is supported by the genomic sequence data, but actual utilization as sole carbon sources for growth has not been observed before this report. Researchers in government, academia and industry will find these results useful, because a better understanding of the metabolic pathways and nutritional requirements of campylobacter bacteria could lead to improvements in culture media for detection and isolation of the pathogen along with future intervention methods to reduce human exposure.

Technical Abstract: Campylobacter spp. readily colonize the intestinal tracts of both human and avian species. While most often a commensal organism in birds, campylobacters remain the leading cause of bacterial gastroenteritis in humans. The association of campylobacters with poultry is well established as a primary route for human exposure. The difference in normal core body temperature between chickens (42°C) and humans (37°C) has been suggested to trigger potential colonization or virulence factors and, indeed, recent studies have demonstrated differential gene expression at the two temperatures. Campylobacter spp. exhibit unique nutritional requirements and have been thought to only utilize amino acids and Kreb cycle intermediates as carbon sources for growth. We evaluated the ability of the genome-sequenced strain of Campylobacter jejuni 11168 to oxidize 190 different substrates as sole carbon sources at 37°C and 42°C using phenotype microarray technology. Results indicate that the expected amino acids, L-serine, L-aspartic acid, L-asparagine, L-proline and L-glutamic acid were utilized in addition to a number of organic acids. In general, oxidation of the substrates was greater at 42°C than at 37°C with a few exceptions. Interestingly, by employing the PM method, we are able to report for the first time the utilization of a number of carbohydrates sources by C. jejuni, including the triose, dihydroxyacetone; the hexose sugar, L-fucose; and the pentose sugars, D-xylose, D-ribose, L-lyxose, and D- and L-arabinose. The presence of genes possibly responsible for utilization of these carbohydrates is supported by the genomic sequence data, but actual utilization as sole carbon sources for growth has not been observed before this report. A better understanding of the metabolic pathways and nutritional requirements of campylobacter could lead to improvements in culture media for detection and isolation of the pathogen and to future intervention methods to reduce human exposure.

Last Modified: 7/28/2014
Footer Content Back to Top of Page