Thiopeptides (thiazolyl peptides) are a class of

peptide Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. ...

antibiotics An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and preventio ...

produced by bacteria. They have antibiotic activity against

Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bac ...

, but little or no activity against

Gram-negative bacteria Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...

. Many of the members of this class show activity against methicillin-resistant ''Staphylococcus aureus'' (MRSA) and are therefore subjects of research interest. There are over 100 members of this class known.

Chemical structure

Thiopeptides are sulfur-rich

macrocyclic Macrocycles are often described as molecules and ions containing a ring of twelve or more atoms. Classical examples include the crown ethers, calixarenes, porphyrins, and cyclodextrins. Macrocycles describe a large, mature area of chemistry. ...

peptides containing highly-modified amino acids. They are characterized by a nitrogen-containing six-membered ring (such as piperidine, dehydropiperidine, or pyridine) substituted with multiple

thiazole Thiazole, or 1,3-thiazole, is a heterocyclic compound that contains both sulfur and nitrogen. The term 'thiazole' also refers to a large family of derivatives. Thiazole itself is a pale yellow liquid with a pyridine-like odor and the molecular fo ...

rings and dehydroamino acids. A macrocylic ring serves as a scaffold for a tail that also incorporates modified amino acids often with

azole Azoles are a class of five-membered heterocyclic compounds containing a nitrogen atom and at least one other non-carbon atom (i.e. nitrogen, sulfur, or oxygen) as part of the ring. Their names originate from the Hantzsch–Widman nomenclature. T ...

rings, such as thiazoles, oxazoles, and thiazolines which are derived from serine, threonine, and cysteine residues.

Examples

Examples of thiopeptides include thiostrepton,

cyclothiazomycin The cyclothiazomycins are a group of natural products, classified as thiopeptides, which are produced by various ''Streptomyces'' species of bacteria. These compounds are ribosomally synthesized and post-translationally modified peptides (RiPPs) a ...

, nosiheptide, and lactocillin.

References

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