The influence of cultural conditions on bacterial cytology.

摘要: Publisher Summary This chapter discusses the influence of cultural conditions on bacterial cytology. There are two mechanisms whereby can alter morphology. First, phenotypic modifications may be directly impressed; such cases form main subject chapter. The inducing condition modifies metabolism all growing cells in culture and within a few generations changes their composition structure. change is nonheritable, acquired character soon lost when again grown absence condition. second mechanism involves an environmentally conditioned selection mutant with altered Small numbers these originate spontaneously parent culture, prolonged or serial cultivation under to which they better adapted than parent-type enables them outgrow replace latter. kind heritable. It stable irreversible, but some cases, reverse mutation occur appropriate reselect original form. Bacterial morphology modified according type balance nutrients medium, pH degree aeration, temperature incubation, presence antibacterial agents, age other factors.