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Genetyczne podłoże oporności bakterii na antybiotyki glikopeptydowe i β-laktamowe

Kubica A., Jatulewicz I.

Chemistry, Environment, Biotechnology

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2012

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Vol. 15

7-17

PL

W artykule przedstawiono mechanizmy oporności bakterii na antybiotyki glikozydowe i β-laktamowe biorąc pod uwagę genetyczne podłoże obniżonej wrażliwości. Omawianie problemu oporności na antybiotyki wymaga opisu aktywności poszczególnych antybiotyków. Informacje te zostaną zawężone tylko do wyjaśnienia głównych mechanizmów działania na komórkę bakteryjną, z pominięciem właściwości chemicznych i farmakokinetycznych leków.

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Wankomycyna i jej chemiczne modyfikacje

Łakomiec A., Samaszko J., Madaj J.

Wiadomości Chemiczne

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2007

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[Z] 61, 3-4

231-245

EN

Antibiotics, such as penicillin or streptomycin, are substances produced by or derived from certain fungi or bacteria, that can destroy or inhibit the growth of other microorganisms. Antibiotics are widely used in the prevention and treatment of infectious diseases. Glycopeptide antibiotics are a class of antibiotic drugs. They consist of a glycosylated cyclic or polycyclic nonribosomal peptide. Important glycopeptide antibiotics include vancomycin, teicoplanin, ramoplanin, and decaplanin. This class of drugs inhibits the synthesis of cell walls in susceptible microbes by inhibiting peptidoglycan synthesis. Glycopeptides exhibit a narrow spectrum of activity as principally effective against gram positive cocci. They are the last line of effective defense against MRSA and multiresistant enterococci for patients who are critically ill. At the beginning of the 90' there started a large scale research program for finding glycopeptide antibiotics with optimized properties. These studes resulted in the discovery of the hemi-synthetic compounds (1996 oritavancin) which have lower toxicity than vancomycin.

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Budowa i synteza glikopeptydów

Samaszko J., Łakomiec A., Madaj J.

Wiadomości Chemiczne

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2007

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[Z] 61, 1-2

79-98

EN

During the past decades it has been recognized that most of the natural proteins of mammals carry covalently linked saccharide side chains. The carbohydrate portions of the glycoproteins as well as those of glycolipids obviously play key roles in biological recognition processes. A glycoprotein is a compound containing carbohydrate (or glycan) covalently linked to protein. The carbohydrate may be in a form of monosaccharide, disaccharide(s), oligosaccharide(s), polysaccharide(s), or their derivatives (e.g. sulfo- or phos-pho-substituted). One, a few, or many carbohydrate units may be present. There are two most common types of glycoproteins: O- and N-glycoproteins. In eukaryotes, the most prevalent type of O-linked glycosylation is the mucin-type glycosylation, where N-acetyl-D-galactosamine (GalNAc) is linked in an ?-anomeric configuration to the ?-hydroxyl group of either a serine or a threonine residue of the polypeptide. Other types of O-linked glycosylation include glycosaminoglycans, such as heparin and chondrotin sulfate, which are attached to the polypeptide chain through ?-linked xylose residues. An older and more prevalent type of glycosylation, N-linked glycosylation, is found in a wide range of organisms ranging from Archae to mammals and other eukaryotes. N-Glycosylation is a modification performed cotranslationally (during the translation of mRNA to protein) and is available to any secreted or membrane-bound protein containing the triplet amino acid sequence AsnXxxSer/Thr (where Xxx is any amino acid except Pro). An oligosaccharide is transferred to the amide side chain of Asn from a dolichol phosphate glycosyl donor, by the action of mem-brane-bound oligosaccharyl transferase in the endoplasmic reticulum (ER). The fully translated glycoprotein is then subject to glycan trimming and processing which is further elaborated in the ER and Golgi apparatus.