Enterococcus is a large genus of lactic acid bacteria of the phylum Bacillota. Enterococci are gram-positive cocci that often occur in pairs (diplococci) or short chains, and are difficult to distinguish from streptococci on physical characteristics alone. Two species are common commensal organisms in the intestines of humans: E. faecalis (90–95%) and E. faecium (5–10%). Rare clusters of infections occur with other species, including E. casseliflavus, E. gallinarum, and E. raffinosus.
Drug resistance is the reduction in effectiveness of a medication such as an antimicrobial or an antineoplastic in treating a disease or condition. The term is used in the context of resistance that pathogens or cancers have "acquired", that is, resistance has evolved. Antimicrobial resistance and antineoplastic resistance challenge clinical care and drive research. When an organism is resistant to more than one drug, it is said to be multidrug-resistant.
Cephems are a sub-group of β-lactam antibiotics including cephalosporins and cephamycins. It is one of the most common 4-membered ring heterocycle. Produced by actinomycetes, cephamycins were found to display antibacterial activity against a wide range of bacteria, including those resistant to penicillin and cephalosporins. The antimicrobial properties of Cephem include the attachment to certain penicillin-binding proteins that are involved in the production of cell walls of bacteria.
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.
Piperacillin is a broad-spectrum β-lactam antibiotic of the ureidopenicillin class. The chemical structure of piperacillin and other ureidopenicillins incorporates a polar side chain that enhances penetration into Gram-negative bacteria and reduces susceptibility to cleavage by Gram-negative beta lactamase enzymes. These properties confer activity against the important hospital pathogen Pseudomonas aeruginosa. Thus piperacillin is sometimes referred to as an "anti-pseudomonal penicillin".
Novobiocin, also known as albamycin, is an aminocoumarin antibiotic that is produced by the actinomycete Streptomyces niveus, which has recently been identified as a subjective synonym for S. spheroides a member of the class Actinomycetia. Other aminocoumarin antibiotics include clorobiocin and coumermycin A1. Novobiocin was first reported in the mid-1950s.
Lincosamides are a class of antibiotics, which include lincomycin, clindamycin, and pirlimycin.
A23187 is a mobile ion-carrier that forms stable complexes with divalent cations. A23187 is also known as Calcimycin, Calcium Ionophore, Antibiotic A23187 and Calcium Ionophore A23187. It is produced at fermentation of Streptomyceschartreusensis.
Streptomyces spectabilis is a bacterium species from the genus of Streptomyces. Streptomyces spectabilis produces hangtaimycin, gentamicin, kanamycin, neomycin B, sisomycin, tobramycin, paromomycin, spectinabilin, spectinomycin, aminocyclitol, actinospectacin, prodigiosine and the streptovaricin complex.
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:
Fleroxacin is a quinolone antibiotic. It is sold under the brand names Quinodis and Megalocin.
Sparsomycin is a compound, initially discovered as a metabolite of the bacterium Streptomyces sparsogenes, which binds to the 50S ribosomal subunit and inhibits protein synthesis through peptidyl transferase inhibition. As it binds to the 50S ribosomal subunit, it induces translocation on the 30S subunit. It is a nucleotide analogue. It was also formerly thought to be a possible anti-tumor agent, but interest in this drug was later discarded after it was discovered that it resulted in retinopathy and as a tool to study protein synthesis; it is not specific for bacterial ribosomes and so not usable as an antibiotic.
SCCmec, or staphylococcal cassette chromosome mec, is a mobile genetic element of Staphylococcus bacterial species. This genetic sequence includes the mecA gene coding for resistance to the antibiotic methicillin and is the only known way for Staphylococcus strains to spread the gene in the wild by horizontal gene transfer. SCCmec is a 21 to 60 kb long genetic element that confers broad-spectrum β-lactam resistance to MRSA. Moreover, additional genetic elements like Tn554, pT181, and pUB110 can be found in SCCmec, which have the capability to render resistance to various non-β-lactam drugs.
Streptomyces alboniger is a bacterium species in the genus Streptomyces.
Streptomyces niveus is a bacterium species from the genus of Streptomyces which has been isolated from soil in the United States. Streptomyces niveus produces the aminocoumarin antibiotic novobiocin and the compounds nivetetracyclate A and nivetetracyclate B.
Streptomyces platensis is a bacterium species from the genus of Streptomyces which has been isolated from soil. Streptomyces platensis produces oxytetracycline, platensimycin, migrastatin, isomigrastatin, platencin, dorrigocin A, dorrigocin B and terramycine.
Streptomyces rishiriensis is a bacterium species from the genus of Streptomyces which has been isolated from soil in Hokkaido in Japan. Streptomyces rishiriensis produces coumermycin A1, notomycin, 2-chloroadenosine, phosphophenylalanarginine and lactonamycin.
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.
Streptomyces wedmorensis is a bacterium species from the genus of Streptomyces which has been isolated from soil in Pennsylvania in the United States. Streptomyces wedmorensis produces (S)-2-hydroxypropylphosphonic acid epoxidase, fosfomycin and phosphonomycin B.
Kluyvera is a Gram negative, facultatively anaerobic bacterial and motile genus from the family of Enterobacteriaceae which have peritrichous flagella. Kluyvera occur in water, soil and sewage. Kluyvera bacteria can cause opportunistic infections in immunocompromised patients.
