Actinomyces are a genus of Gram-positive, rod-shaped bacteria that are generally considered to be part of the normal microbiota of humans and other animals. They are typically found in the mouth, respiratory tract, and gastrointestinal tract. Actinomyces are sensitive to many antibiotics, including penicillins, cephalosporins, macrolides, and tetracyclines. They can also be sensitive to metronidazole and chloramphenicol. Additionally, Actinomyces can be susceptible to certain antifungal agents such as amphotericin B and flucytosine.
Actinomyces have a unique resistance to certain antibiotics, such as vancomycin, and are relatively resistant to certain antiseptics, such as chlorhexidine. They also have an inherent resistance to sugar, which can be used as a diagnostic tool. Furthermore, Actinomyces have a low tolerance for environmental changes, such as changes in temperature or pH, and are sensitive to osmotic pressure.
In terms of environmental factors, Actinomyces are sensitive to high levels of oxygen and can be inhibited by anaerobic conditions. They are also sensitive to certain disinfectants, such as phenol and chlorine, and can be killed by heat and ultraviolet light. Additionally, Actinomyces are sensitive to certain surfactants, such as polysorbate 80, and can be inhibited by organic solvents, such as ethanol and propylene glycol. Finally, Actinomyces are sensitive to certain antifungal medications, such as ketoconazole and itraconazole.