Macrolides are a class of mostly natural products with a large macrocyclic lactone ring to which one or more deoxy sugars, usually cladinose and desosamine, may be attached. The lactone rings are usually 14-, 15-, or 16-membered. Macrolides belong to the polyketide class of natural products. Some macrolides have antibiotic or antifungal activity and are used as pharmaceutical drugs. Rapamycin is also a macrolide and was originally developed as an antifungal, but has since been used as an immunosuppressant drug and is being investigated as a potential longevity therapeutic.
Aminoglycoside is a medicinal and bacteriologic category of traditional Gram-negative antibacterial medications that inhibit protein synthesis and contain as a portion of the molecule an amino-modified glycoside (sugar). The term can also refer more generally to any organic molecule that contains amino sugar substructures. Aminoglycoside antibiotics display bactericidal activity against Gram-negative aerobes and some anaerobic bacilli where resistance has not yet arisen but generally not against Gram-positive and anaerobic Gram-negative bacteria.
Clindamycin is a lincosamide antibiotic medication used for the treatment of a number of bacterial infections, including osteomyelitis (bone) or joint infections, pelvic inflammatory disease, strep throat, pneumonia, acute otitis media, and endocarditis. It can also be used to treat acne, and some cases of methicillin-resistant Staphylococcus aureus (MRSA). In combination with quinine, it can be used to treat malaria. It is available by mouth, by injection into a vein, and as a cream or a gel to be applied to the skin or in the vagina.
Listeria is a genus of bacteria that acts as an intracellular parasite in mammals. As of 2024, 28 species have been identified. The genus is named in honour of the British pioneer of sterile surgery Joseph Lister. Listeria species are Gram-positive, rod-shaped, and facultatively anaerobic, and do not produce endospores.
Tigecycline, sold under the brand name Tygacil, is a tetracycline antibiotic medication for a number of bacterial infections. It is a glycylcycline class drug that is administered intravenously. It was developed in response to the growing rate of antibiotic resistant bacteria such as Staphylococcus aureus, Acinetobacter baumannii, and E. coli. As a tetracycline derivative antibiotic, its structural modifications has expanded its therapeutic activity to include Gram-positive and Gram-negative organisms, including those of multi-drug resistance.
Glycylcyclines are a class of antibiotics derived from tetracycline. These tetracycline analogues are specifically designed to overcome two common mechanisms of tetracycline resistance, namely resistance mediated by acquired efflux pumps and/or ribosomal protection. Presently, tigecycline is the only glycylcycline approved for antibiotic use.
Lincosamides are a class of antibiotics, which include lincomycin, clindamycin, and pirlimycin.
Tetracyclines are a group of broad-spectrum antibiotic compounds that have a common basic structure and are either isolated directly from several species of Streptomyces bacteria or produced semi-synthetically from those isolated compounds. Tetracycline molecules comprise a linear fused tetracyclic nucleus to which a variety of functional groups are attached. Tetracyclines are named after their four ("tetra-") hydrocarbon rings ("-cycl-") derivation ("-ine"). They are defined as a subclass of polyketides, having an octahydrotetracene-2-carboxamide skeleton and are known as derivatives of polycyclic naphthacene carboxamide. While all tetracyclines have a common structure, they differ from each other by the presence of chloro, methyl, and hydroxyl groups. These modifications do not change their broad antibacterial activity, but do affect pharmacological properties such as half-life and binding to proteins in serum.
50S is the larger subunit of the 70S ribosome of prokaryotes, i.e. bacteria and archaea. It is the site of inhibition for antibiotics such as macrolides, chloramphenicol, clindamycin, and the pleuromutilins. It includes the 5S ribosomal RNA and 23S ribosomal RNA.
EF-G is a prokaryotic elongation factor involved in mRNA translation. As a GTPase, EF-G catalyzes the movement (translocation) of transfer RNA (tRNA) and messenger RNA (mRNA) through the ribosome.
A protein synthesis inhibitor is a compound that stops or slows the growth or proliferation of cells by disrupting the processes that lead directly to the generation of new proteins.
Streptogramin A is a group of antibiotics within the larger family of antibiotics known as streptogramins. They are synthesized by the bacteria Streptomyces virginiae. The streptogramin family of antibiotics consists of two distinct groups: group A antibiotics contain a 23-membered unsaturated ring with lactone and peptide bonds while group B antibiotics are depsipeptides. While structurally different, these two groups of antibiotics act synergistically, providing greater antibiotic activity than the combined activity of the separate components. These antibiotics have until recently been commercially manufactured as feed additives in agriculture, although today there is increased interest in their ability to combat antibiotic-resistant bacteria, particularly vancomycin-resistant bacteria.
Solithromycin is a ketolide antibiotic undergoing clinical development for the treatment of community-acquired pneumonia and other infections.
Bottromycin is a macrocyclic peptide with antibiotic activity. It was first discovered in 1957 as a natural product isolated from Streptomyces bottropensis. It has been shown to inhibit methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) among other Gram-positive bacteria and mycoplasma. Bottromycin is structurally distinct from both vancomycin, a glycopeptide antibiotic, and methicillin, a beta-lactam antibiotic.
Cyclic di-AMP is a second messenger used in signal transduction in bacteria and archaea. It is present in many Gram-positive bacteria, some Gram-negative species, and archaea of the phylum Euryarchaeota.
Odilorhabdins are a class of natural antibacterial agents produced by the bacterium Xenorhabdus nematophila. Odilorhabdins act against both Gram-positive and Gram-negative pathogens, and were shown to eliminate infections in mouse models.
Pyrrhocoricin is a 20-residue long antimicrobial peptide of the firebug Pyrrhocoris apterus.
Oxepanoprolinamides are a class of antibiotics. They include iboxamycin. These drugs are fully synthetic. The molecules contain the aminooctose component of clindamycin. They were developed by Andrew G. Myers and Yury S. Polikanov. The structure contains an oxepane and a proline, with an amide group that increases rigidity.
Parvulin-like peptidyl-prolyl isomerase (PrsA), also referred to as putative proteinase maturation protein A (PpmA), functions as a molecular chaperone in Gram-positive bacteria, such as B. subtilis, S. aureus, L. monocytogenes and S. pyogenes. PrsA proteins contain a highly conserved parvulin domain that contains peptidyl-prolyl cis-trans isomerase (PPIase) activity capable of catalyzing the bond N-terminal to proline from cis to trans, or vice versa, which is a rate limiting step in protein folding. PrsA homologs also contain a foldase domain suspected to aid in the folding of proteins but, unlike the parvulin domain, is not highly conserved. PrsA proteins are capable of forming multimers in vivo and in vitro and, when dimerized, form a claw-like structure linked by the NC domains. Most Gram-positive bacteria contain only one PrsA-like protein, but some organisms such as L. monocytogenes, B. anthracis and S. pyogenes contain two PrsAs.
Cresomycin is an experimental antibiotic. It binds to the bacterial ribosome in both Gram-negative and Gram-positive bacteria, and it has been found to be effective against multi-drug-resistant stains of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. It belongs to the bridged macrobicyclic oxepanoprolinamide antibiotics, which have similarities with lincosamides antibiotics.
