Microbiology 1 [ULM/MB-GM1/09]

In diagnostics of infectious diseases direct and indirect diagnostic methods are used. Direct diagnostics allows to visualize microorganisms as agents of infection, indirect diagnostics allows to detect reactions of the macroorganism to the presence of the microorganism. Indirect diagnostics is focused on cellular immunity (skin tests), in which specific antibodies are demonstrated by serological reactions. The lecture is devoted to the explanation of basic terms (antigen, antibody, serological reaction, its course, evaluation) and the classification of serological reactions, which are used in clinical microbiology in the diagnosis of infectious disease agents. An illustrative image or procedure, reaction principle and specific examples of use are available for individual reactions.

Genetic information is stored in all cells in the form of a DNA, nucleic acid molecule. A segment of DNA that codes for a molecule with a specific function is a gene. It represents the basic unit of genetic information. In bacteria, DNA is most often found in the form of one chromosome and several smaller plasmids.

The family of Mycobacteriaceae contains the single genus Mycobacterium with over 150 species. They are broadly distributed in various natural environments, and with several notable exceptions, they do not appear in parasitic or disease associations. This genus also includes Mycobacerium tuberculosis, currently responsible for serious bacterial infections of humans in many parts of the world, with millions of deaths annually. Other Mycobacterium species can cause a variety of infections as well; for example, worldwide, there are over quarter million new cases of leprosy, a debilitating disease caused by Mycobacterium leprae. A number of mycobacterial saprophytes have been shown to cause opportunistic infections in immunocompromised individuals, and many are pathogens of animals.