Streptomyces sudanensis is a form of actinobacteria. The bacteria in this group are mostly beneficial, but few specific species can cause disease. While drugs are derived from many forms of Actinobacteria, Streptomyces sudanensis, which has recently been reexplored, is hazardous to human health.
What is Streptomyces sudanensis?
Streptomyces are notable for their resemblance to fungi. They are rod-shaped, like all actinomycetes. The prefix “strepto” denotes the chain-like arrangement. Streptomycetes grow strung together in chain-like, net-like branches, making them resemble a fungal mesh (mycelium).
Occurrence, distribution, and characteristics
Streptomycetes live, on the one hand, in that soil which is formed by the final stage of decomposition of dead animals or plant parts. Thus, they contribute to the maintenance of ecological balance. The characteristic odor of the soil is due to the production of the odorant geosmin by the bacteria. On the other hand, they are also found in the intestines of worms and insects as digestive bacteria. Streptomyces are distinguished, among other things, according to the place of their occurrence. The bacterium is found worldwide. In Europe, the bacterium occurs sporadically due to the temperate climatic conditions, in the tropics, such as Sudan and India (Madras) it is very common. The bacterium enters the body through the smallest injuries (e.g. wood splinters) or poor oral hygiene. Inadequately maintained and decaying teeth, as well as gum disease, can spread the bacterium. In the case of damaged teeth or gingivitis, the infection can also be caused by jaw surgery. Streptomycec sudanensis is a Gram-positive bacterium, i.e. it turns blue by Gram staining, which reveals the substance of its cell wall (murein), which, however, cannot be called a cell membrane. Gram-negative bacteria have a cell membrane composed of lipids. The staining procedure in microscopy, named after the Danish bacteriologist Hans-Christian Gram, is used to classify bacteria. Streptomycec sudanensis is aerobic, meaning that metabolism is oxygen-dependent. The bacterium does not live on photosynthesis. Therefore, Streptomyces sudanensis is classified as a bacterium and not in the plant kingdom or the fungal kingdom. Streptomyces sudanensis, along with Streptomyces somaliensis and Streptomyces madurae, is a tropical form of actinobacteria that is hazardous to human health.
Importance and function
Actinomycetes in general are essential for the existence of living nature, as the decomposition of dead material allows other life forms to thrive, which humans also feed on. Also, the transformation of decaying material into soil prevents contamination by dead carcasses. The bacteria do not normally occur in the human body and cannot harm it if there are no injuries. Streptomyces are even used to produce various groups of antibiotics, such as amoxicillin for urinary tract infections, as well as agents against Candida fungal diseases (such as nystatin). Many species of actinomycetes are dangerous to plants and animals. Adequate hygiene and defense strengthening, protected handling of infected secretions, wearing shoes, immediate disinfection of small wounds, and avoidance of injury hazards are important to prevent infection.
Diseases and medical conditions
Streptomyces sudanensis can cause mycetoma, an initially painless, chronic skin inflammation. This is a tropical disease with a long incubation period. Dense swellings occur first, usually on the calf, foot, or hands. Fistulas filled with granules later form on the skin of the affected part of the body, secreting a purulent fluid. If left untreated, the infection can spread to the lungs, intestines, meninges, and bones as the pus foci spread. Lung involvement can cause pneumonia, brain involvement can cause meningitis, and bone involvement can cause bone erosion. In the worst cases, the course can lead to deformity of the limbs or life-threatening blood poisoning in particularly susceptible individuals. The infection is diagnosed by medical examination, bacterial and fungal cultures, from the pus coming out of the fistulas.The disease does not heal on its own and must be treated with antibiotics (e.g. penicillin) for months or years. It is curable in the early stages. If it is far advanced, foci of infection or entire limbs must be surgically removed. Travel to the tropics involves certain dangers, especially if the trip is to the countryside and if there are minor injuries to the hand or foot. The rest of the body is less at risk for developing the fistulas than the limbs. Vaccines against actinomycetoma caused by Streptomyces sudanensis are not known. Agricultural workers, as well as people who have to work outdoors in inhumane conditions or at risk of injury, are particularly affected and at risk. Weakness of the immune system, also due to malnutrition, old age or longstanding illnesses can complicate the course of the disease. The socioeconomic situation of the affected person, as well as the general medical care and hygiene standards in the country concerned, play a decisive role.
