Influence of nitrogen source on low temperature growth of verotoxigenic Escherichia coli

• Published in: Food microbiology Vol. 15; no. 3; pp. 355 - 364
• Main Authors: Kauppi, K.L, O'Sullivan, D.J, Tatini, S.R
• Format: Journal Article
• Language: English
• Published: London Elsevier 01.06.1998
• Subjects: ammonium sulfate; bacterial toxins; Bacteriology; Biological and medical sciences; casamino acids; casein hydrolysate; cold; culture media; Escherichia coli; Food industries; Food microbiology; free amino acids; Fundamental and applied biological sciences. Psychology; growth; Growth, nutrition, cell differenciation; low temperature growth; Microbiology; nutrient availability; peptides; strains; tryptone media; verotoxigenic strains; Microorganism growth; Peptides; Escherichia coli; Environmental factor; Shiga-like toxin; Carbon; Nutrient source; Aminoacid; Pathogenic; Microorganism culture; Bacteria; Nitrogen Organic compounds; Enterobacteriaceae; Low temperature
• ISSN: 0740-0020; 1095-9998
• DOI: 10.1006/fmic.1997.0174

The influence of organic and inorganic nitrogen sources on low temperature growth of Shiga-like verotoxin-producing Escherichia coli (VTEC) was studied. Seven verotoxigenic strains were studied in complex and minimal medium systems. Results indicate that verotoxigenic strains require an organic nitrogen source (amino acids or peptides) for growth at 6.5 degrees C. Minimal medium systems containing ammonium sulfate as the nitrogen source and glucose as the carbon source did not support the growth of any strain at 6.5 degrees C. However, glucose and fructose minimal media systems with ammonia sulfate as the source of nitrogen supported growth at 9.5 degrees C. Amino acids and/or peptides could serve as the source of nitrogen, carbon and energy for growth of some VTEC at 6.5 degrees C. These results suggest that VTEC can readily grow at 6.5 degrees C owing to the availability of organic nitrogen sources and sugars in foods.