AbaR5, a Large Multiple-Antibiotic Resistance Region Found in Acinetobacter baumannii

Abstract

A multiply antibiotic-resistant Acinetobacter baumannii strain, 3208, contains the aacC1-orfP-orfP-orfQaadA1 gene cassette array; sul1, tetA(A), and aphA1b genes; and a mer operon in a large region containing a novel transposon, Tn6020, and segments of Tn1696, Tn21, Tn1721, and Tn5393. This region is part of a genomic resistance island, AbaR5, related to and found in the same chromosomal position as AbaR1. This strain is the first European clone I isolate detected in Australia.

Use of the Accessory Genome for Characterization and Typing of Acinetobacter baumannii

“…Detection of the presence of an AbaR island by insertion in comM and detection of the AbaR-comM junction were carried out with primers described by Post et al (21). Those for other elements (e.g., IS26, bla TEM , and aphA1) that can be found in AbaR islands were as used by Post and others (4,12,20). Primers for a copper resistance D gene (AB57_0657, ABAYE3207, and A1S_2941); cusS (coding for a sensor kinase; AB57_0660, ABAYE3204, and A1S_2938); a putative pilus subunit gene, filA (ABAYE3128 and ACICU_00635); a phage terminase gene (AB57_1270 and ACICU_02185); esvB (for ethanol-stimulated virulence; A1S_1232, ABAYE2526, ACICU_01218, and AB57_1375); a toxin-antitoxin target (ACICU_2140); a macrolide efflux pump gene (mel) (as in GenBank accession number EF102240); and a molybdate system target (ACICU_1787) were designed from regions of sequence that were common to all isolates for which sequence was available.…”

“…In addition, a number of "AbaR"-type resistance islands, inserted in an ATPase gene (here called comM) and carrying genes associated with resistance to antibiotics and heavy metals, have been described previously (1,2,11,16,17,20,21). The latter show diversity, with that described in an isolate of international clone II (AbaR2 in ACICU) being considerably smaller than that found in isolates of international clone I; among the latter, a number of different islands have already been described.…”

Genetic basis of antibiotic resistance in pathogenic Acinetobacter species

“…This 86-kb resistance island, designated AbaR1, contained [40 antibiotic or heavy metal resistance genes, including the bla VEB-1 ESBL gene (42). Other AbaR elements have been identified in different multidrug-resistant A. baumannii isolates, and one has been identified in the multidrug-susceptible A. baumannii strain SDF (47)(48)(49). To date, all AbaR elements have been chromosomally located, being inserted into the comM gene that encodes a putative ATPase.…”

Identification and Isolation of Insertion Sequences, in Carbapenem Resistant Clinical Isolates of Acinetobacter baumannii from Tehran Hospitals

“…These enzymes are classified into four main OXA subfamilies: OXA-23-like, OXA-24/40-like, OXA-58-like, and OXA-51-like that the latest one is chromosomally located in all A. baumannii strains. Thus, it is an important genetic marker in the identification of these bacteria (7,8). OXA types have a weak hydrolysis property but they are usually associated with genetic elements such as insertion sequences to increase the expression of carbapenemases and also mobilize them (7,9).…”

“…Thus, it is an important genetic marker in the identification of these bacteria (7,8). OXA types have a weak hydrolysis property but they are usually associated with genetic elements such as insertion sequences to increase the expression of carbapenemases and also mobilize them (7,9). genes, such as bla OXA-23-like genes, bla OXA-51-like genes, and bla OXA-58-like genes, it increases their expression to a level that confers resistance to carbapenem (5,10,11).…”