عنوان

Mobilome and antibiotic resistance in acinetobacter baumannii

Number

TL48942

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Mobilome and antibiotic resistance in acinetobacter baumannii

General Material Designation

[Thesis]

First Statement of Responsibility

Andres Felipe Opazo

Name of Publisher, Distributor, etc.

The University of Edinburgh (United Kingdom)

Date of Publication, Distribution, etc.

2014

Specific Material Designation and Extent of Item

0

Text of Note

Place of publication: United States, Ann Arbor;

Dissertation or thesis details and type of degree

Ph.D.

Body granting the degree

The University of Edinburgh (United Kingdom)

Text preceding or following the note

2014

Text of Note

Acinetobacter baumannii is an important microorganism involved in hospital-acquired infections with a remarkable ability to develop resistance to multiple antibiotics (multidrug-resistance, MDR) which makes it a highly troublesome pathogen in many hospitals around the world. Third-generation cephalosporins (such as ceftazidime) and carbapenems (such as imipenem and meropenem) represent important treatment options for infections caused by this microorganism. Nevertheless, the number of strains resistant to these antibiotics has been increasing during the last decade. The ability to capture, mobilise and regulate the expression of resistance-genes of this microorganism is a cornerstone factor in the development of the MDR, where the Mobilome, defined as "all the mobile genetic elements in a cell", is responsible for its genetic plasticity. The aim of this work was to analyse the role of insertion sequences (ISs), transposon-like structures, resistance-plasmids and ISCR1-like elements in the resistance to carbapenems and ceftazidime in A. baumannii. Fifteen carbapanem-resistant strains of Acinetobacter baumannii isolated from Chile and two ceftazidime-resistant strains from the United Arab Emirates were studied. Different ceftazidime- and carbapenem-resistance genes were analysed and their genetic environments were characterised. The Mobilome in the carbapenem-resistant strains was composed of insertion sequences (ISs), specifically by ISAba1 associated with blaOXA-51-like, ISAba3 associated to blaOXA-58, which in turn was detected in two different plasmids, and ISAba15 interrupting ISAba3. In the case of the ceftazidime-resistant strain, the presence of an ISCR1 element was harbouring the blaPER-7, which was detected in a megaplasmid. The Mobilome, in the strains analysed, was composed of a wide variety of genetic elements, such as plasmids, insertion sequences, ISCR-like elements, which reflects the ability of A. baumannii to use different genetic platforms to capture and use resistance genes, making the Mobilome an important contributor in the resistance and the dissemination of resistance genes among nosocomial pathogens around the world.

Subject Term

(UMI)AAI10174290;Social sciences

Islam, Md Shahidul

The University of Edinburgh (United Kingdom)

Call Number

1827510592; 10174290

Electronic name

p

[Thesis]

276903

a

Y