Microbiota which can also be called normal microflora is the totality of microorganisms that are inherently present in a particular environment, body or location at every specific point of time. Mycoflora are fungal organisms that live in particular sites of the body without causing infection or disease. Microbiota goes into competition with pathogens on and in the human body with a view to subverting their pathogenic and virulent activities within the host. They do this through a process called amensalism (a bacterial interference mechanism). In amensalism, normal microflora utilize available space, nutrients and other resources in the host (required by the pathogen to cause infection and disease) and produce substances that resist their disease-causing mechanisms in the host.
Amensalism is an adverse microbe-microbe interaction in which the product or activity of one microorganism has a harmful effect on another microorganism. However, microbiota can turn form being harmless microorganisms to becoming potential pathogens to a host in some exceptional cases. Others can also become opportunistic microorganisms which only cause disease in the host by chance i.e. when the environment or body of the individual favors their blossoming (e.g., in an immunocompromised case such as in an AIDS patients or an individual whose immune system has been suppressed due to therapy). The overuse of antibiotics, stress and nutritional imbalance in human beings can cause their microbiota to become pathogenic in nature. It should also be noted that different materials and substances (whether clinical or of non-clinical origin) have their own microflora which are well-known and very unique to them.
The microbiologist should acquaint him or herself on the basic knowledge of the different microbiota that make up different parts of the human body or the environment from which the samples they will be working with in the laboratory are actually made up of. This will allow the scientist to make concrete conclusions on the inferences drawn from a particular research or test so that the final judgment of an experiment is not based on the microbiota (which are not harmful and might not necessarily be the target or cause of the malady being deciphered).
The human body is well inundated with beneficial microorganisms which help to keep infectious organisms at bay; and these organisms (i.e. normal microflora) confer other health benefits to the individual (Figure 1). It is worth mentioning that the foetus in the womb of a pregnant woman (i.e., in utero) is free from normal microflora. Humans starts developing and forming their microbiota few seconds after delivery as microorganisms colonizes their external and internal body parts. Infants become colonized with a plethora of microorganisms and commensals which all constitutes their normal microflora; and this process of microbiota colonization in the infant commences soon after birth and this continues as the infant grows. Some internal tissues of a healthy human being including blood, brain, muscles and cerebrospinal fluid are normally germ free i.e., they are free from microorganisms and are said to be sterile.
Figure 1: Human anatomy showing sites of the body colonized by microorganisms.
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