Bradley, S. Gaylen Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, Virginia.
Last reviewed:August 2019
- Diversity and distribution
- Identification and classification
- Molecular biology
- Related Primary Literature
- Additional Reading
A heterogeneous collection of bacteria with diverse ecologies and physiologies. The initial definition was based on their branching filamentous cellular morphology during a stage of the growth cycle. The name actinomycete means “ray fungus,” and for many years the actinomycetes were erroneously considered to be fungi, or at least closely related to the fungi. True fungi, such as the common bread mold, also grow as branching filaments (hyphae) that are several micrometers in diameter, whereas those of the actinomycetes are about 1 μm in diameter. The genetic material of the eukaryotic true fungi consists of DNA associated with proteins, and is enclosed in a membrane (the nucleus), whereas the genetic material of the prokaryotic actinomycetes consists of free DNA in direct contact with the cell sap (cytoplasm). In general, actinomycetes do not have membrane-bound organelles, whereas the fungi have an array of organelles such as mitochondria and vacuoles. The cell walls of fungi are made of chitin or cellulose, whereas the cell walls of the actinomycetes are made of a cross-linked polymer containing short chains of amino acids and long chains of amino sugars. Actinomycetes are susceptible to a wide range of antibiotics used to treat bacterial diseases, such as penicillin and tetracycline. See also: Amino acids; Antibiotic; Deoxyribonucleic acid (DNA); Fungi
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Contributors include more than 9000 highly qualified scientists and 43 Nobel Prize winners.
MORE THAN 8700 articles covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 19,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information