The Actinomycetota are a phylum of mostly Gram-positive bacteria. They can be terrestrial or aquatic. They are of great economic importance to humans because agriculture and forests depend on their contributions to soil systems. In soil they help to decompose the organic matter of dead organisms so the molecules can be taken up anew by plants. While this role is also played by fungi, Actinomycetota are much smaller and likely do not occupy the same ecological niche. In this role the colonies often grow extensive mycelia, like a fungus would, and the name of an important order of the phylum, Actinomycetales, reflects that they were long believed to be fungi. Some soil actinomycetota live symbiotically with the plants whose roots pervade the soil, fixing nitrogen for the plants in exchange for access to some of the plant's saccharides. Other species, such as many members of the genus Mycobacterium, are important pathogens.
Streptomyces is the largest genus of Actinomycetota and the type genus of the family Streptomycetaceae. Over 500 species of Streptomyces bacteria have been described. As with the other Actinomycetota, streptomycetes are gram-positive, and have genomes with high GC content. Found predominantly in soil and decaying vegetation, most streptomycetes produce spores, and are noted for their distinct "earthy" odor that results from production of a volatile metabolite, geosmin.
DD-transpeptidase is a bacterial enzyme that catalyzes the transfer of the R-L-aca-D-alanyl moiety of R-L-aca-D-alanyl-D-alanine carbonyl donors to the γ-OH of their active-site serine and from this to a final acceptor. It is involved in bacterial cell wall biosynthesis, namely, the transpeptidation that crosslinks the peptide side chains of peptidoglycan strands.
Clavulanic acid is a β-lactam drug that functions as a mechanism-based β-lactamase inhibitor. While not effective by itself as an antibiotic, when combined with penicillin-group antibiotics, it can overcome antibiotic resistance in bacteria that secrete β-lactamase, which otherwise inactivates most penicillins.
Production of antibiotics is a naturally occurring event, that thanks to advances in science can now be replicated and improved upon in laboratory settings. Due to the discovery of penicillin by Alexander Flemming, and the efforts of Florey and Chain in 1938, large-scale, pharmaceutical production of antibiotics has been made possible. As with the initial discovery of penicillin, most antibiotics have been discovered as a result of happenstance. Antibiotic production can be grouped into three methods: natural fermentation, semi-synthetic, and synthetic. As more and more bacteria continue to develop resistance to currently produced antibiotics, research and development of new antibiotics continues to be important. In addition to research and development into the production of new antibiotics, repackaging delivery systems is important to improving efficacy of the antibiotics that are currently produced. Improvements to this field have seen the ability to add antibiotics directly into implanted devices, aerosolization of antibiotics for direct delivery, and combination of antibiotics with non antibiotics to improve outcomes. The increase of antibiotic resistant strains of pathogenic bacteria has led to an increased urgency for the funding of research and development of antibiotics and a desire for production of new and better acting antibiotics.
The Streptomycetaceae are a family of Actinomycetota, making up the monotypic order Streptomycetales. It includes the important genus Streptomyces. This was the original source of many antibiotics, namely streptomycin, the first antibiotic against tuberculosis.
Aminocoumarin is a class of antibiotics that act by an inhibition of the DNA gyrase enzyme involved in the cell division in bacteria. They are derived from Streptomyces species, whose best-known representative – Streptomyces coelicolor – was completely sequenced in 2002. The aminocoumarin antibiotics include:
Hachimycin, also known as trichomycin, is a polyene macrolide antibiotic. It's used as a fungicidal antifungal agent, derived from streptomyces.
Streptomyces griseus is a species of bacteria in the genus Streptomyces commonly found in soil. A few strains have been also reported from deep-sea sediments. It is a Gram-positive bacterium with high GC content. Along with most other streptomycetes, S. griseus strains are well known producers of antibiotics and other such commercially significant secondary metabolites. These strains are known to be producers of 32 different structural types of bioactive compounds. Streptomycin, the first antibiotic ever reported from a bacterium, comes from strains of S. griseus. Recently, the whole genome sequence of one of its strains had been completed.
Clavams are a class of antibiotics. This antibiotic is derived from Streptomyces clavuligerus NRRL 3585. Clavam is produced to form a new β-lactam antibiotic. This class is divided into the clavulanic acid class and the 5S clavams class. Clavulanic acid is a broad-spectrum antibiotic and 5S clavams may have anti-fungal properties. They are similar to penams, but with an oxygen substituted for the sulfur. Thus, they are also known as oxapenams.
Streptomyces hygroscopicus is a bacterial species in the genus Streptomyces. It was first described by Hans Laurits Jensen in 1931.
Carbomycin, also known as magnamycin, is a colorless, optically active crystalline macrolide antibiotic with the molecular formula C42H67NO16. It is derived from the bacterium Streptomyces halstedii and active in inhibiting the growth of Gram-positive bacteria and "certain Mycoplasma strains." Its structure was first proposed by Robert Woodward in 1957 and was subsequently corrected in 1965.
Streptomyces isolates have yielded the majority of human, animal, and agricultural antibiotics, as well as a number of fundamental chemotherapy medicines. Streptomyces is the largest antibiotic-producing genus of Actinomycetota, producing chemotherapy, antibacterial, antifungal, antiparasitic drugs, and immunosuppressants. Streptomyces isolates are typically initiated with the aerial hyphal formation from the mycelium.
Mervyn James Bibb FRS is an Emeritus Fellow at the John Innes Centre, Norwich, UK.
Streptomyces albidoflavus is a bacterium species from the genus of Streptomyces which has been isolated from soil from Poland. Streptomyces albidoflavus produces dibutyl phthalate and streptothricins.
Streptomyces arenae is a bacterium species from the genus Streptomyces which has been isolated from soil from Illinois in the United States. Streptomyces arenae produces pentalenolactone, 2,5-dihydrophenylalanine, naphthocyclinone and arenaemycine.
Streptomyces canarius is a bacterium species from the genus of Streptomyces. Streptomyces canarius produces saphenamycin and canarius.
Streptomyces griseoaurantiacus is a thermotolerant bacterium species from the genus of Streptomyces which was isolated from marine sediment. Streptomyces griseoaurantiacus produces the antibiotics manumycin, diperamycin and chinikomycin, and griseolic acid.
Streptomyces griseoflavus is a bacterium species from the genus of Streptomyces which has been isolated from garden soil. Streptomyces griseoflavus produces bicozamycin, colabomycins A, colabomycins C, germacradienol and hormaomycin.
Streptomyces virginiae is a bacterium species from the genus of Streptomyces which has been isolated from soil. Streptomyces virginiae produces actithiazic acid, virginiamycins and cycloserine. Streptomyces virginiae also produces monensin A, monensin B, monensin C, monensin D, actithiazic acid.
