Analysis of Complete Genome Sequence of Acinetobacter baumannii Strain ATCC 19606 Reveals Novel Mobile Genetic Elements and Novel Prophage.

Mohammad Hamidian,Joyce To,María Tomas,Garry S A Myers,Lucia Blasco,Lauren N Tillman

doi:10.3390/microorganisms8121851

Mohammad Hamidian, Joyce To + Show 4 more

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https://doi.org/10.3390/microorganisms8121851

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Journal: Microorganisms	Publication Date: Nov 24, 2020
Citations: 19	License type: CC BY 4.0

Affiliation: University of Technology Sydney

Abstract

Acinetobacter baumannii isolate ATCC 19606 was recovered in the US prior to 1948. It has been used as a reference and model organism in many studies involving antibiotic resistance and pathogenesis of A. baumannii, while, until recently, a complete genome of this strain was not available. Here, we present an analysis of the complete 3.91-Mbp genome sequence, generated via a combination of short-read sequencing (Illumina) and long-read sequencing (MinION), and show it contains two small cryptic plasmids and a novel complete prophage of size 41.2 kb. We also characterised several regions of the ATCC 19606 genome, leading to the identification of a novel cadmium/mercury transposon, which was named Tn6551. ATCC 19606 is an antibiotic-sensitive strain, but a comparative analysis of all publicly available ST52 strains predicts a resistance to modern antibiotics by the accumulation of antibiotic-resistance genes via plasmids in recent isolates that belong to this sequence type.

Highlights

Acinetobacter baumannii is a Gram-negative opportunistic pathogen that has emerged in recent decades as a global challenge to healthcare
We previously showed that DNA fragments containing an ISAba1-activated ampC gene or an entire genomic island could be acquired from an exogenous source via homologous recombination [22,23]
No homology was obtained for any known phage, suggesting that the prophage we found in ATCC 19606 is a novel phage

Summary

Introduction

Acinetobacter baumannii is a Gram-negative opportunistic pathogen that has emerged in recent decades as a global challenge to healthcare. A. baumannii ATCC 19606 was recovered in a urine sample prior to 1948 in the US and is one of the earliest isolates available in current collections [5]. It is one of the most antibiotic susceptible strains available to researchers and, has been widely used in studies both as a reference and model strain for studying the emergence and evolution of resistance, pathogenesis and for the discovery of new antibacterial targets [6,7]

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