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26-446: PAMP may refer to: Pathogen-associated molecular pattern , molecules associated with groups of pathogens PAMP (company) , short for Produits Artistiques Métaux Précieux , a precious metals refining and fabricating company, subsidiary of the Swiss company MKS pamp may mean pico amperes, pA, see Ampere PAMP (phenylanisylmethylphosphine)

52-441: A heterodimer of with TLR1 or TLR6 . Lipoteichoic acid (LTA) from gram-positive bacteria , bacterial lipoproteins (sBLP), a phenol soluble factor from Staphylococcus epidermidis , and a component of yeast walls called zymosan , are all recognized by a heterodimer of TLR2 and TLR1 or TLR6. However, LTAs result in a weaker pro-inflammatory response compared to lipopeptides, as they are only recognized by TLR2 instead of

78-680: A higher tolerance towards variation of temperature and pH, making them very interesting for use in a wide range of applications. Iturins are pore‐forming lipopeptides with antifungal activity, and this is dependent on the interaction with the cytoplasmic membrane of the target cells. Mycosubtilin is an iturin isoform that can interact with membranes via its sterol alcohol group, to target ergosterol (a compound found in fungi) to give it antifungal properties. Fengycins are another class of biosurfactant produced by Bacillus subtilis, with antifungal activity against filamentous fungi. There are two classes of Fengycins, Fengycin A and Fengycin B, with

104-522: A kind of spherical assembly made up of many molecules of lipids and some apolipoproteins . Depending on the type of fatty acid attached to the protein, a proteolipid can often contain myristoyl , palmitoyl , or prenyl groups . These groups each serve different functions and have different preferences as to which amino acid residue they attach to. The processes are respectively named myristoylation (usually at N-terminal Gly ), palmitoylation (to cysteine ), and prenylation (also to cysteine). Despite

130-566: A pathogen receptor, in combination with a MAMP, has been proposed as one way to constitute a (pathogen-specific) PAMP. Plant immunology frequently treats the terms "PAMP" and "MAMP" interchangeably, considering their recognition to be the first step in plant immunity, PTI (PAMP-triggered immunity), a relatively weak immune response that occurs when the host plant does not also recognize pathogenic effectors that damage it or modulate its immune response. Mycobacteria are intracellular bacteria which survive in host macrophages . The mycobacterial wall

156-412: A poorly-understood mechanism. All bacteria use proteolipids, sometimes confusingly referred to as bacterial lipoproteins, in their cell membrane. A common modification consists of N-acyl- and S‑diacylglycerol attached to an N-terminal cystine residue. Braun's lipoprotein , found in gram-negative bacteria , is a representative of this group. In addition, Mycobacterium O- mycolate proteins destined for

182-538: A wide range of industries. As the name implies, surfactins are potent biosurfactants ( surfactants produced by bacteria , yeast , or fungi ), and they have been shown to reduce the surface tension of water from 72 to 27 mN/m at very low concentrations. Furthermore, surfactins are also able to permeabilize lipid membranes , allowing them to have specific antimicrobial and antiviral activities. Since surfactins are biosurfactants, they have diverse functional properties. These include low toxicity, biodegradability and

208-823: Is a protein covalently linked to lipid molecules, which can be fatty acids , isoprenoids or sterols . The process of such a linkage is known as protein lipidation , and falls into the wider category of acylation and post-translational modification . Proteolipids are abundant in brain tissue, and are also present in many other animal and plant tissues. They include ghrelin , a peptide hormone associated with feeding. Many proteolipids have bound fatty acid chains, which often provide an interface for interacting with biological membranes and act as lipidons that direct proteins to specific zones. Proteolipids were discovered serendipitously in 1951 by Jordi Folch Pi and Marjorie Lees while extracting sulfatides from brain lipids. They are not to be confused with lipoproteins ,

234-477: Is a precursor to the chemical compound DIPAMP Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title PAMP . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=PAMP&oldid=845748306 " Category : Disambiguation pages Hidden categories: Short description

260-519: Is composed of lipids and polysaccharides and also contains high amounts of mycolic acid. Purified cell wall components of mycobacteria activate mainly TLR2 and also TLR4 . Lipomannan and lipoarabinomannan are strong immunomodulatory lipoglycans. TLR2 with association of TLR1 can recognize cell wall lipoprotein antigens from Mycobacterium tuberculosis , which also induce production of cytokines by macrophages . TLR9 can be activated by mycobacterial DNA. Bacterial lipoprotein A proteolipid

286-681: Is detected by the toll-like receptor TLR4, LPs are detected by TLR2. Many proteolipids are produced by the Bacillus subtilis family, and are composed of a cyclic structure made up of 7-10 amino acids, and a β-hydroxy fatty acid chain of varying length ranging from 13-19 carbon atoms. These can be divided into three families depending on the structure of the cyclic peptide sequence: surfactins, iturins, and fengycins. Lipidated peptides produced by Bacillus strains have many useful bio-activities such as anti-bacterial, anti- viral, anti-fungal, and anti-tumour properties, making them very attractive for use in

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312-445: Is different from Wikidata All article disambiguation pages All disambiguation pages Pathogen-associated molecular pattern Although the term "PAMP" is relatively new, the concept that molecules derived from microbes must be detected by receptors from multicellular organisms has been held for many decades, and references to an "endotoxin receptor" are found in much of the older literature. The recognition of PAMPs by

338-454: Is the conserved structural motif that is recognized by TLR4, particularly the TLR4-MD2 complex. Microbes have two main strategies in which they try to avoid the immune system, either by masking lipid A or directing their LPS towards an immunomodulatory receptor. Peptidoglycan (PG) is also found within the membrane walls of gram-negative bacteria and is recognized by TLR2, which is usually in

364-473: Is used as an antibiotic to treat life-threatening conditions caused by Gram positive bacteria including MRSA (methicillin-resistant Staphylococcus aureus) and vancomycin resistant Enterococci. As with the Bacillus subtilis lipidated peptides, the permeation of the cell membrane is what gives it its properties, and the mechanism of action with daptomycin is thought to involve the insertion of the decanoyl chain into

390-674: The pH range 3-7, in addition to stimulating human dermal and corneal fibroblasts in a concentration dependant manner, suggesting that stimulation occurs above the critical aggregation concentration. There exist some rarer forms of protein acylation that may not have a membrane-related function. They include serine O-octanoylation in ghrelin , serine O- palmitoleoylation in Wnt proteins , and O-palmitoylation in histone H4 with LPCAT1 . Hedgehog proteins are double-modified by (N-)palmitate and cholesterol. Some skin ceramides are proteolipids. The amino group on lysine can also be myristoylation via

416-805: The PRRs triggers activation of several signaling cascades in the host immune cells like the stimulation of interferons (IFNs) or other cytokines. A vast array of different types of molecules can serve as PAMPs, including glycans and glycoconjugates . Flagellin is also another PAMP that is recognized via the constant domain, D1 by TLR5 . Despite being a protein, its N- and C-terminal ends are highly conserved, due to its necessity for function of flagella. Nucleic acid variants normally associated with viruses , such as double-stranded RNA ( dsRNA ), are recognized by TLR3 and unmethylated CpG motifs are recognized by TLR9 . The CpG motifs must be internalized in order to be recognized by TLR9. Viral glycoproteins, as seen in

442-412: The approved drugs are long-acting anti-diabetic GLP-1 analogues liraglutide (Victoza®), and insulin detemir (Levemir®). The other two are the antibiotics daptomycin and polymyxin B . Lipidated peptides also have applications in other areas, such as use in the cosmetic industry. A commercially available lipidated peptide, Matrixyl , is used in anti-wrinkle creams. Matrixyl is a pentapeptide and has

468-422: The heterodimer. First introduced by Charles Janeway in 1989, PAMP was used to describe microbial components that would be considered foreign in a multicellular host. The term "PAMP" has been criticized on the grounds that most microbes, not only pathogens, express the molecules detected; the term microbe-associated molecular pattern (MAMP), has therefore been proposed. A virulence signal capable of binding to

494-453: The hydrophilic/hydrophobic balance, as well interactions between the peptide units, which is dependent on the charge of the amino acid residues. Lipidated peptides combine the structural features of amphiphilic surfactants with the functions of bioactive peptides , and they are known to assemble into a variety of nanostructures. Due to the desirable properties of peptides such as high receptor affinity and bioactivity , and low toxicity,

520-468: The main immunogens of these two species. Proteolipids include bacterial antibiotics that aren't synthesised in the ribosome . Products of nonribosomal peptide synthase may also involve a peptide structure linked to lipids. These are usually referred to as "lipopeptides". Bacterial "lipoproteins" and "lipopeptides" (LP) are potent inducers of sepsis , second only to lipopolysaccharide (LPS) in its ability to cause an inflammation response. While LPS

546-407: The outer membrane. The plant chloroplast is capable of many of the same modifications that bacteria perform to proteolipids. One database for such N-Acyl Diacyl Glycerylated cell wall proteolipids is DOLOP. Pathogenic spirochetes, including B. burgdorferi and T. pallidum , use their proteolipid adhesins to stick to victim cells. These proteins are also potent antigens , and are in fact

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572-452: The seemingly specific names, N-myristoylation and S-palmitoylation can also involve some other fatty acids, most commonly in plants and viral proteolipids. The article on lipid-anchored proteins has more information on these canonical classes. Lipidated peptides are a type of peptide amphiphile that incorporate one or more alkyl/lipid chains, attached to a peptide head group. As with peptide amphiphiles , they self-assemble depending on

598-467: The sequence KTTKS, with an attached palmitoyl lipid chain , that is able to stimulate collagen and fibronectin production in fibroblasts. Several studies have shown promising results of palmitoyl-KTTKS, and topical formulations have been found to significantly reduce fine lines and wrinkles, helping to delay the aging process in the skin. The Hamley group have also carried out investigations of palmitoyl-KTTKS, and found it so self-assemble into nano tapes in

624-502: The two only differing by one amino acid at position 6 in the peptide sequence, with the former having an alanine residue, and the latter having valine. Daptomycin is another naturally occurring lipidated peptide, produced by the Gram positive bacterium Streptomyces roseoporous . The structure of Daptomycin consists of a decanoyl lipid chain attached to a partially cyclised peptide head group. It has very potent antimicrobial properties and

650-504: The use of peptides in therapeutics (i. e. as peptide therapeutics ) has great potential; shown by a fast growing market with over 100 approved peptide-based drugs. The disadvantages are that peptides have low oral bioavailability and stability. Lipidation as a chemical modification tool in the development of therapeutic agents has proven to be useful in overcoming these issues, with four lipidized peptide drugs currently approved for use in humans, and various others in clinical trials. Two of

676-399: The viral-envelope, as well as fungal PAMPS on the cell surface or fungi are recognized by TLR2 and TLR4 . Bacterial lipopolysaccharides (LPSs), also known as endotoxins , are found on the cell membranes of gram-negative bacteria , are considered to be the prototypical class of PAMPs. The lipid portion of LPS, lipid A, contains a diglycolamine backbone with multiple acyl chains. This

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