This 1966 study investigated the nutritional requirements for growth of three Pasteurella species at 28°C and 37°C on defined agar media. At 28°C, P. pseudotuberculosis strains either required no growth factors or depended on thiamine or pantothenate. Most P. pestis strains required cystine, methionine, and phenylalanine, though some strains could dispense with methionine or phenylalanine. Pasteurella 'X' strains were either thiamine-dependent or required no factors. At 37°C, all strains showed increased nutritional demands. P. pseudotuberculosis strains required combinations of glutamic acid, thiamine, cystine, and pantothenate, with some strains also requiring nicotinamide. P. pestis required multiple amino acids and vitamins including cystine, methionine, phenylalanine, glycine, valine, isoleucine, glutamic acid, and thiamine, with optimal growth in CO₂-enriched air. Pasteurella 'X' strains consistently required thiamine and either cystine or methionine at 37°C. Testing virulent and avirulent P. pestis strains revealed similar calcium requirements on defined media, contradicting earlier claims of differential requirements. The findings provide foundations for developing selective media and auxotrophic mutants for genetic studies of these species.

Key findings

• P. pseudotuberculosis strains require minimal factors at 28°C (none to thiamine/pantothenate) but increased requirements at 37°C (combinations of glutamic acid, thiamine, cystine, pantothenate, and sometimes nicotinamide)
• P. pestis shows complex nutritional requirements at 28°C (cystine, methionine, phenylalanine) and 37°C (eight factors including amino acids and thiamine, with optimal growth in CO₂-enriched air)
• Pasteurella 'X' (Yersinia enterocolitica) shows relatively simple requirements: independent of factors or thiamine-dependent at 28°C; requiring thiamine plus either cystine or methionine at 37°C
• Virulent and avirulent P. pestis strains show no differential calcium requirements on defined media, contrary to previous findings using complete media
• Temperature significantly influences nutritional demands across all three species, with 37°C requiring substantially more growth factors than 28°C