Study on the relation between oxidative assimilation and phase of H. pertussis.

Freshly isolated strains of H. pertussis show meagre growth on Bordet Gengou medium, but a series of subcultures after isolation on the medium containing decreasing amounts of blood results in an ability to grow on blood-free medium, eventually demonstrating that the organisms become to thrive on ordinary agar medium. Imamura (1952), Asano (1953) and Fukumi et al. (1953) reported that H. pertussis of phase I required glutamic acid as the most important nitrogenous requirement, cysteine as a sulfur-containing compound and nicotinic acid as the growth factor. According to their findings, this organism seems to be not so much exacting in its nutritional requirements as expected from its meagre growth on such an enriched medium as Bordet Gengou medium. Proom (1955), however, stated that this organism could grow in a simple amino acids mixture only for one or two subcultures and did not survive in further serial subcultures in such media. As it is unreasonable, however, to think that the faint growth of H. pertussis on Bordet Gengou medium enriched with 1% peptone is due to shortage of nutrients, the authors tried to investigate this problem from another point, apart from the investigations on nutritional requirements. Since 1939, Clifton and his colleagues (Clifton, 1946; Clifton, 1947; Siegel et al., 1950) and Wiame et al., (1951) reported the results on oxidative assimilation of microorganisms and demonstrated that there were definite stoichiometric relationships between dissimilation and assimilation concerning to a given substrate utilized by microorganisms. It was also reported by Clifton et al., that Candida albicans and S. cerevisiae have a higher energy efficiency in utilization of substrate than E. coli and P. calco-acetica. These studies using non-exacting organisms suggested to the authors that the last crop in their growth might depend upon the stoichiometric balances between dissimilation and assimilation for substrates in the medium in which the organisms were cultured, as well as upon their growth factors. As it is known that H. pertussis in the course of phase variation shows