ABSTRACT
This chapter presents a very brief synopsis of what the researchers know about the indigenous microbiota of humans based on the results of culture-dependent and culture-independent studies. It discusses the possibility that human bloodstream may also support a microbiota. The proportions of the various bacterial phyla at a number of representative body sites, as revealed by culture-independent approaches. The chapter outlines the main gaps in people knowledge of the human microbiota and list some of the many important questions about people microbial symbionts that need to be answered. The archaea that inhabit humans appear to have a more limited distribution on the body than bacteria and have been detected only in the gastrointestinal tract and oral cavity and on the skin of healthy individuals. Culture-independent analysis, like culture-based approaches, has also found that the communities present at the various body sites are comprised mainly of bacteria from four phyla—Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes.
