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  1. Neuraminidase inhibitor - Wikipedia

    Neuraminidase inhibitors (NAIs) are a class of drugs which block the neuraminidase enzyme. They are commonly used as antiviral drugs because they block the function of viral neuraminidases of the influenza virus, by preventing its reproduction by budding from the host cell.

  2. Neuraminidase - Wikipedia

    Neuraminidase (Sialidase) enzymes are glycoside hydrolase enzymes that cleave (cut) the glycosidic linkages of neuraminic acids. Neuraminidase enzymes are a large family, found in a range of organisms. The best-known neuraminidase is the viral neuraminidase, a drug target for the prevention of the spread of influenza infection.

  3. Discovery and development of neuraminidase inhibitors - Wikipedia
    • Overview
    • History
    • Influenza virus
    • The substrate
    • Mechanism of action
    • Development

    Neuraminidase inhibitors inhibit enzymatic activity of the enzyme neuraminidase. These type of inhibitors have been introduced as anti-influenza drugs as they prevent the virus from exiting infected cells and thus stop further spreading of the virus. Neuraminidase inhibitors for human neuraminidase have the potential to be useful drugs as the enzyme plays a role in several signaling pathways in cells and is implicated in diseases such as diabetes and cancer.

    The first neuraminidase Inhibitors were synthesized in the 1960s by Edmond et al., through an attempt to understand the catalytic mechanism of the neuraminidase enzyme. They discovered that N-substituted oxamic acids had enzyme inhibitory properties. Then it was found that the synthetic compound 2-deoxy-2,3-didehydro-N-acetylneuraminic acid which is an analogue of N-acetylneuraminic acid, inhibits the release of virus progeny in tissue culture but no antiviral activity in animals was detected. I

    The Influenza virus is an RNA virus that is divided into three serological types: A, B and C. Hemagglutinin and neuraminidase are two important glycoproteins on influenza virus membranes. The hemagglutinin is a sialic acid receptor-binding molecule and mediates entry of the virus into the host cell, while neuraminidase cleaves cellular-receptor sialic acid to form new particles. Neuraminidase is an exoglycosidase that destroys the hemagglutinin receptor by cleaving the α- or α-ketosidic ...

    N-acetylneuraminic acid is one of the two most common sialic acid in mammals. It is a monosaccharide with a backbone of 9 carbons. It is usually attached to glycoproteins or gangliosides on a terminal end via α, α, and α linkage. Neuraminidase is an enzyme which hydrolyses that bond to produce a free neuraminic acid and a glycoprotein or a sugar chain. Influenza virus will bind via the hemagglutinin protein on these sialic acid attached glycoproteins on the cell membrane.

    The mechanism of NA has been shown to proceed with the retention of configuration which means it preserves the absolute configuration on the atom in the stereocenter. There are four steps of catalytic pathways. In the first step, the binding step, the carboxylate group changes fr

    There are two types of neuraminidase inhibitors commonly available for treatment and prophylaxis of influenza infections: Zanamivir and Oseltamivir. They interfere with the release of progeny virions from infected host cells, prevent infection process of new host cells and stop s

    Influenza virus neuraminidase consists of 4 co-planar roughly spherical subunits predominantly made of β-sheets, characterized as a 6-fold β-propeller and a hydrophobic region embedded in the virus’ membrane. The active site is located near the middle of the pseudo ...

    2-deoxy-2,3-didehydro-N-acetylneuraminic acid is a pan-selective inhibitor for neuraminidase. Neu5Ac2en is a dehydrogenated Neu5Ac and can be synthesized by the hNEU enzyme if Neu5Ac is in high enough concentration. Neu5Ac is also a mild inhibitor for the enzyme but as Neu5Ac2en

    Zanamivir and Oseltamivir have been tested as hNEU inhibitors. Only Zanamivir shows moderate inhibition activity for hNEU. Isoenzyme selective inhibitors could potentially be very important. At present there are limited studies for the hNEU substrate specificity. DANA is a pan-se

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  5. Viral neuraminidase - Wikipedia
    • Overview
    • Function
    • Inhibitors
    • Specificity
    • Exo- and endo-

    Viral neuraminidase is a type of neuraminidase found on the surface of influenza viruses that enables the virus to be released from the host cell. Neuraminidases are enzymes that cleave sialic acid groups from glycoproteins and are required for influenza virus replication. Viral neuraminidases are the members of the Glycoside hydrolase family 34 CAZY GH_34 which comprises enzymes with only one known activity; sialidase or neuraminidase EC Neuraminidases cleave the terminal sialic acid

    The enzyme helps viruses to be released after budding from the plasma membrane of a host cell. Influenza virus membranes contain two glycoproteins: hemagglutinin and neuraminidase. While the hemagglutinin on the surface of the virion is needed for infection, its presence inhibits release of the particle after budding. Viral neuraminidase cleaves terminal neuraminic acid residues from glycan structures on the surface of the infected cell. This promotes the release of progeny viruses and the sprea

    Neuraminidase has been targeted in structure-based enzyme inhibitor design programmes that have resulted in the production of two drugs, zanamivir and oseltamivir. Administration of neuraminidase inhibitors is a treatment that limits the severity and spread of viral infections. Neuraminidase inhibitors are useful for combating influenza infection: zanamivir, administered by inhalation; oseltamivir, administered orally; and under research is peramivir administered parenterally, that is through in

    In ideal circumstances, influenza virus neuraminidase should act on the same type of receptor the virus hemagglutinin binds to, a phenomenon that does not always happen. It is not quite clear how the virus manages to function when there is no close match between the specificities of NA and HA.

    Neuraminidase enzymes can have endo- or exo-glycosidase activity, and are classified as EC and EC In general, mammalian sialic acid residues are at terminal positions in complex glycans, and so viral neuraminidases - which are exo-glycosidase enzymes - use these terminal residues as their substrates.

  6. Neuraminidase inhibitors - Osmosis

    Mar 25, 2020 · Neuraminidase inhibitors are antiviral medications mainly used to treat influenza, which is the virus that causes the flu.. There are three types of influenza viruses that infect humans; type A, type B, and type C, and each one has a slightly different genome and set of proteins.

  7. Discovery and development of neuraminidase inhibitors - WIKI 2
    • History
    • Influenza Virus
    • The Substrate
    • Mechanism of Action
    • Development
    • Usage
    • Drug Resistance

    The first neu­raminidase In­hibitors (NAIs) were syn­the­sized in the 1960s by Ed­mond et al., through an at­tempt to un­der­stand the cat­alytic mech­a­nism of the neu­raminidase en­zyme. They dis­cov­ered that N-sub­sti­tuted ox­amic acids had en­zyme in­hibitory prop­er­ties. Then it was found that the syn­thetic com­pound 2-de­oxy-2,3-dide­hy­dro-N-acetyl­neu­raminic acid (Neu5Ac2en or DANA) which is an ana­logue of N-acetyl­neu­raminic acid (Neu5Ac), in­hibits the re­lease of virus prog­eny in tis­sue cul­ture but no an­tivi­ral ac­tiv­ity in an­i­mals was detected.In the early 1990s, the de­ter­mi­na­tion of bi­o­log­i­cal crys­tal struc­tureof in­fluenza virus sur­face pro­tein led to the dis­cov­ery of the ac­tive site and pro­vided the op­por­tu­ni­ties to dis­cover and de­sign new and spe­cific in­hibitors.

    The In­fluenza virus is an RNA virus that is di­vided into three sero­log­i­cal types: A, B and C. Hemag­glu­tinin (HA) and neu­raminidase (NA) are two im­por­tant gly­co­pro­teins on in­fluenza virus mem­branes. The hemag­glu­tinin is a sialic acid re­cep­tor-bind­ing mol­e­cule and me­di­ates entry of the virus into the host cell, while neu­raminidase cleaves cel­lu­lar-re­cep­tor sialic acid to form new par­ti­cles. Neu­raminidase is an ex­o­gly­cosi­dase that de­stroys the hemag­glu­tinin re­cep­tor by cleav­ing the α(2,6)- or α(2,3)-ke­to­sidic link­age that ex­ists be­tween a ter­mi­nal sialic acid and a sugar residue of the Neu5Ac con­tain­ing re­cep­tor on the sur­face of host cells. This helps the spread of the in­fec­tion by pre­vent­ing self-ag­gre­ga­tion of new viruses at the cell sur­face and pos­si­ble im­mo­bil­i­sa­tion in the mucin by hemag­glu­tinin (HA) dur­ing virus repli­ca­tion. The virus will then be re­leased from the host cells and will sub­se­quently in­fe...

    N-acetyl­neu­raminic acid (Neu5Ac) is one of the two most com­mon sialic acid in mammals. It is a mono­sac­cha­ride with a back­bone of 9 car­bons. It is usu­ally at­tached to gly­co­pro­teins or gan­glio­sides on a ter­mi­nal end via α(2,3), α(2,6), and α(2,8) linkage.Neu­raminidase is an en­zyme which hy­drol­y­ses that bond to pro­duce a free neu­raminic acid and a gly­co­pro­tein or a sugar chain. In­fluenza virus will bind via the hemag­glu­tinin pro­tein on these sialic acid at­tached gly­co­pro­teins on the cell membrane.

    Mechanism of enzyme catalysis

    The mech­a­nism of NA has been shown to pro­ceed with the re­ten­tion of con­fig­u­ra­tion which means it pre­serves the ab­solute con­fig­u­ra­tion on the atom in the stereocenter. There are four steps of cat­alytic path­ways. In the first step, the bind­ing step, the car­boxy­late group changes from the axial po­si­tion into the pseudo-equa­to­r­ial po­si­tion. The sec­ond step is the pro­ton do­na­tion from water mol­e­cule and for­ma­tion of the en­do­cyclic sialo­syl cation tran­si­tion-...

    Mechanism of inhibition

    There are two types of neu­raminidase in­hibitors com­monly avail­able for treat­ment and pro­phy­laxis of in­fluenza in­fec­tions: Zanamivir and Os­eltamivir. They in­ter­fere with the re­lease of prog­eny viri­onsfrom in­fected host cells, pre­vent in­fec­tion process of new host cells and stop spread of in­fec­tion in res­pi­ra­tory tract by mim­ic­k­ing nat­ural sub­strate and fit­ting into ac­tive site of neu­raminidase en­zyme. They in­ter­rupt the de­tach­ment of prog­eny viri­ons. Vir...

    Viral neuraminidase inhibitors

    2-de­oxy-2,3-dide­hy­dro-N-acetyl­neu­raminic acid (Neu5Ac2en) is a pan-se­lec­tive in­hibitor for neu­raminidase. Neu5Ac2en is a de­hy­dro­genated Neu5Ac and can be syn­the­sized by the hNEU en­zyme if Neu5Ac is in high enough con­cen­tra­tion. Neu5Ac is also a mild in­hibitor for the en­zyme but as Neu5Ac2en is a tran­si­tion-state ana­logue it is a much bet­ter inhibitor.

    Structures of the Viral neuraminidase inhibitors in use

    *Only Zanamivir and Oseltamivir are FDA approved. Peramivir is used in Japan and South Korea. Laninamivir is used in Japan only.

    Recent development and design of analogues of viral inhibitors

    New NA in­hibitor ana­logues were syn­the­sized, based on Zanamivir, Os­eltamivir and Peramivir, with ra­tio­nal struc­ture-based drug de­sign and can be cat­e­go­rized into four groups.

    There are 2 sub­groups of NA in­hibitors that have been ap­proved by reg­u­la­tory au­thor­i­ties in the US and Eu­rope, Zanamivir and Os­eltamivir. Both are for the treat­ment and pre­ven­tion of in­fluenza. Fur­ther­more, Peramivir and Lan­i­namivir have been ap­proved by reg­u­la­tory au­thor­i­ties in some parts of Asia.

    Cur­rently, there are two classes of an­tivi­ral drugs ap­proved for the treat­ment and pro­phy­laxis of in­fluenza in­fec­tions. They are the adaman­tanes and NAIs. The adaman­tanes only work on in­fluenza A so since 2010 WHO rec­om­mended the usage of NAIs for treat­ment and pro­phy­laxis of in­fluenza A and B infections. In con­trast to adaman­tanes, NAIs are less toxic and less prone to pro­mote drug-re­sis­tant in­fluenza. More­over, they are ef­fec­tive against all neu­raminidase sub­types and all strains of in­fluenza. After the in­fluenza pan­demic in 2009, there has been great con­cern about viral re­sis­tance to NAIs.In­fluenza viruses that have re­duced sen­si­tiv­ity to NAIs often con­tain mu­ta­tion that af­fect the shape of the NA cat­alytic site and there­fore re­duce the bind­ing abil­ity of the in­hibitors. The cat­alytic site of the NA has eight func­tional residues ( R118, D151, R152, R224, E276, R292, R371, and Y406) sur­rounded by eleven frame­work residues (E11...

  8. Neuraminidase inhibitors (NAIs) are a class of drugs which block the neuraminidase enzyme. They are commonly used as antiviral drugs because they block the function of viral neuraminidases of the influenza virus, by preventing its reproduction by budding from the host cell. Oseltamivir (Tamiflu) a prodrug, Zanamivir (Relenza), Laninamivir (Inavir), and Peramivir belong to this class. Unlike ...

  9. Inhibitor neuraminidase - Wikipedia bahasa Indonesia ...

    Neuraminidase inhibitor (NAIs) adalah golongan obat yang menghambat enzim neuraminidase. Obat ini biasa digunakan sebagai obat antivirus karena menghambat fungsi virus neuraminidase virus influenza, dengan mencegah reproduksinya oleh tunas dari sel inang. Oseltamivir (Tamiflu) prodrug, Zanamivir (Relenza), Laninamivir (Inavir), dan Peramivir ...

  10. Zanamivir - Wikipedia

    Zanamivir was the first of the neuraminidase inhibitors. The discovery was initially funded by the Australian biotechnology company Biota and was part of Biota's ongoing program to develop antiviral agents through rational drug design. Its strategy relied on the availability of the structure of influenza neuraminidase by X-ray crystallography.

  11. List of Neuraminidase inhibitors -

    Neuraminidase inhibitors are drugs that block the function of the viral neuraminidase protein. By blocking this protein enzyme it stops the release of viruses from the infected host cell and prevents new host cells from being infected.