Aerobic or facultative anaerobic

Spore formation is limited almost entirely to two genera of rodshaped bacteria Bacillus (aerobic or facultatively anaerobic), and Clostridium (anaerobic or aerotolerant). With one possible exception, the common spherical bacteria do not sporulate. Some spore-bearing species can be made to lose their ability to produce spores. When the ability to produce spores is once lost, it is seldom regained. SporMation is not a process to increase bacterial numbers because a cell rarely produces more than one spore. 

Salmonella A genus of rod-shaped Gramnegative bacteria that inhabit the intestine and cause disease (salmonellosis) in humans and animals. They are aerobic or facultatively anaerobic, and most are motile. 

Conform bacterium Gram-negative, nonspore-forming, aerobic or facultatively anaerobic bacterium that ferments lactose and produces acid and gas, significant numbers may indicate water pollution. 

The only surfaces available for colonization in the edentulous infant are epithelial surfaces and bacteria are continually removed from these by the shedding of surface cells. The pioneer organisms are aerobes or facultative anaerobes, usually streptococci and lactobacilli. Once invasion has occurred, the complexity of the oral communities increases during the next few months, particularly on the new surfaces provided by the eruption of the teeth. A list of common oral organisms together with some of their properties is shown in Table 33.2. 

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