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Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm

Enzymatic modification is a prevalent mechanism by which bacteria defeat the action of antibiotics. Aminoglycosides are often inactivated by aminoglycoside modifying enzymes encoded by genes present in the chromosome, plasmids, and other genetic elements. The AAC(6′)-Ib (aminoglycoside 6′-N-acetyltr...

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Autores principales: Ramirez, María S., Nikolaidis, Nikolas, Tolmasky, Marcelo E.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3656343/
https://www.ncbi.nlm.nih.gov/pubmed/23730301
http://dx.doi.org/10.3389/fmicb.2013.00121
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author Ramirez, María S.
Nikolaidis, Nikolas
Tolmasky, Marcelo E.
author_facet Ramirez, María S.
Nikolaidis, Nikolas
Tolmasky, Marcelo E.
author_sort Ramirez, María S.
collection PubMed
description Enzymatic modification is a prevalent mechanism by which bacteria defeat the action of antibiotics. Aminoglycosides are often inactivated by aminoglycoside modifying enzymes encoded by genes present in the chromosome, plasmids, and other genetic elements. The AAC(6′)-Ib (aminoglycoside 6′-N-acetyltransferase type Ib) is an enzyme of clinical importance found in a wide variety of gram-negative pathogens. The AAC(6′)-Ib enzyme is of interest not only because of his ubiquity but also because of other characteristics, it presents significant microheterogeneity at the N-termini and the aac(6′)-Ib gene is often present in integrons, transposons, plasmids, genomic islands, and other genetic structures. Excluding the highly heterogeneous N-termini, there are 45 non-identical AAC(6′)-Ib related entries in the NCBI database, 32 of which have identical name in spite of not having identical amino acid sequence. While some variants conserved similar properties, others show dramatic differences in specificity, including the case of AAC(6′)-Ib-cr that mediates acetylation of ciprofloxacin representing a rare case where a resistance enzyme acquires the ability to utilize an antibiotic of a different class as substrate. Efforts to utilize antisense technologies to turn off expression of the gene or to identify enzymatic inhibitors to induce phenotypic conversion to susceptibility are under way.
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spelling pubmed-36563432013-05-31 Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm Ramirez, María S. Nikolaidis, Nikolas Tolmasky, Marcelo E. Front Microbiol Microbiology Enzymatic modification is a prevalent mechanism by which bacteria defeat the action of antibiotics. Aminoglycosides are often inactivated by aminoglycoside modifying enzymes encoded by genes present in the chromosome, plasmids, and other genetic elements. The AAC(6′)-Ib (aminoglycoside 6′-N-acetyltransferase type Ib) is an enzyme of clinical importance found in a wide variety of gram-negative pathogens. The AAC(6′)-Ib enzyme is of interest not only because of his ubiquity but also because of other characteristics, it presents significant microheterogeneity at the N-termini and the aac(6′)-Ib gene is often present in integrons, transposons, plasmids, genomic islands, and other genetic structures. Excluding the highly heterogeneous N-termini, there are 45 non-identical AAC(6′)-Ib related entries in the NCBI database, 32 of which have identical name in spite of not having identical amino acid sequence. While some variants conserved similar properties, others show dramatic differences in specificity, including the case of AAC(6′)-Ib-cr that mediates acetylation of ciprofloxacin representing a rare case where a resistance enzyme acquires the ability to utilize an antibiotic of a different class as substrate. Efforts to utilize antisense technologies to turn off expression of the gene or to identify enzymatic inhibitors to induce phenotypic conversion to susceptibility are under way. Frontiers Media S.A. 2013-05-17 /pmc/articles/PMC3656343/ /pubmed/23730301 http://dx.doi.org/10.3389/fmicb.2013.00121 Text en Copyright © 2013 Ramirez, Nikolaidis and Tolmasky. http://creativecommons.org/licenses/by/3.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.
spellingShingle Microbiology
Ramirez, María S.
Nikolaidis, Nikolas
Tolmasky, Marcelo E.
Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm
title Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm
title_full Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm
title_fullStr Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm
title_full_unstemmed Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm
title_short Rise and dissemination of aminoglycoside resistance: the aac(6′)-Ib paradigm
title_sort rise and dissemination of aminoglycoside resistance: the aac(6′)-ib paradigm
topic Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3656343/
https://www.ncbi.nlm.nih.gov/pubmed/23730301
http://dx.doi.org/10.3389/fmicb.2013.00121
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