Modeling Multispecies Gene Flow Dynamics Reveals the Unique Roles of Different Horizontal Gene Transfer Mechanisms

In response to evolving environmental, production, and processing conditions, microbial communities have tremendous abilities to move toward increased diversity and fitness by various pathways such as vertical and horizontal gene transfer mechanisms, biofilm formation, and quorum sensing [...]

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Fluorescence-Based Detection of Natural Transformation in Drug-ResistantAcinetobacter baumannii

Journal of Bacteriology ◽

10.1128/jb.00181-18 ◽

2018 ◽

Vol 200 (19) ◽

Cited By ~ 11

Author(s):

Anne-Sophie Godeux ◽

Agnese Lupo ◽

Marisa Haenni ◽

Simon Guette-Marquet ◽

Gottfried Wilharm ◽

...

Keyword(s):

Flow Cytometry ◽

Antibiotic Resistance ◽

Gene Transfer ◽

Horizontal Gene Transfer ◽

Natural Transformation ◽

Multidrug Resistant ◽

New Method ◽

Content Type ◽

Transfer Mechanisms ◽

Multiple Antibiotics

ABSTRACTAcinetobacter baumanniiis a nosocomial agent with a high propensity for developing resistance to antibiotics. This ability relies on horizontal gene transfer mechanisms occurring in theAcinetobactergenus, including natural transformation. To study natural transformation in bacteria, the most prevalent method uses selection for the acquisition of an antibiotic resistance marker in a target chromosomal locus by the recipient cell. Most clinical isolates ofA. baumanniiare resistant to multiple antibiotics, limiting the use of such selection-based methods. Here, we report the development of a phenotypic and selection-free method based on flow cytometry to detect transformation events in multidrug-resistant (MDR) clinicalA. baumanniiisolates. To this end, we engineered a translational fusion between the abundant and conservedA. baumanniinucleoprotein (HU) and the superfolder green fluorescent protein (sfGFP). The new method was benchmarked against the conventional antibiotic selection-based method. Using this new method, we investigated several parameters affecting transformation efficiencies and identified conditions of transformability one hundred times higher than those previously reported. Using optimized transformation conditions, we probed natural transformation in a set of MDR clinical and nonclinical animalA. baumanniiisolates. Regardless of their origin, the majority of the isolates displayed natural transformability, indicative of a conserved trait in the species. Overall, this new method and optimized protocol will greatly facilitate the study of natural transformation in the opportunistic pathogenA. baumannii.IMPORTANCEAntibiotic resistance is a pressing global health concern with the rise of multiple and panresistant pathogens. The rapid and unfailing resistance to multiple antibiotics of the nosocomial agentAcinetobacter baumannii, notably to carbapenems, prompt to understand the mechanisms behind acquisition of new antibiotic resistance genes. Natural transformation, one of the horizontal gene transfer mechanisms in bacteria, was only recently described inA. baumanniiand could explain its ability to acquire resistance genes. We developed a reliable method to probe and study natural transformation mechanism inA. baumannii. More broadly, this new method based on flow cytometry will allow experimental detection and quantification of horizontal gene transfer events in multidrug-resistantA. baumannii.

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Conserved Filamentous Prophage in Escherichia coli O18:K1:H7 and Yersinia pestis Biovar orientalis

Journal of Bacteriology ◽

10.1128/jb.184.21.6050-6055.2002 ◽

2002 ◽

Vol 184 (21) ◽

pp. 6050-6055 ◽

Cited By ~ 53

Author(s):

Mark D. Gonzalez ◽

Carol A. Lichtensteiger ◽

Ruth Caughlan ◽

Eric R. Vimr

Keyword(s):

Escherichia Coli ◽

Gene Transfer ◽

Horizontal Gene Transfer ◽

Yersinia Pestis ◽

Relative Location ◽

Single Stranded Dna ◽

E Coli ◽

High Virulence ◽

Transfer Mechanisms

ABSTRACT Microbial virulence is known to emerge by horizontal gene transfer mechanisms. Here we describe the discovery of a novel filamentous prophage, designated CUS-1, which is integrated into the chromosomal dif homologue of the high-virulence clone Escherichia coli O18:K1:H7. An homologous chromosomal element (CUS-2) in Yersinia pestis biovar orientalis is integrated at the same relative location as CUS-1; both lysogenic E. coli and Y. pestis strains produce particles with properties expected of single-stranded DNA virions. CUSφ is epidemiologically correlated with the emergence of K1 strains with increased virulence and with the Y. pestis biovar responsible for the current (third) plague pandemic.

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Horizontal gene transfer: mechanisms and evolutionary consequences

Origins and Evolution of Life ◽

10.1017/cbo9780511933875.022 ◽

2011 ◽

pp. 313-325

Author(s):

David Moreira

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Evolutionary Consequences ◽

Transfer Mechanisms

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Selfish, promiscuous, and sometimes useful: how mobile genetic elements drive horizontal gene transfer in microbial populations

10.32942/osf.io/7t2jh ◽

2021 ◽

Author(s):

Eduardo P. C. Rocha ◽

Matthieu Haudiquet ◽

Jorge Moura de Sousa ◽

Marie Touchon

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Cell Envelope ◽

Horizontal Transmission ◽

Donor Cell ◽

Mobile Genetic Elements ◽

Microbial Populations ◽

Genetic Elements ◽

Transfer Mechanisms ◽

Host Genes

Horizontal gene transfer (HGT) drives microbial adaptation but is often under the control of mobile genetic elements (MGEs) whose interests are not necessarily aligned with those of their hosts. In general, transfer is costly to the donor cell while potentially beneficial to the recipients. The diversity and plasticity of cell-MGEs interactions, and those among MGEs, results in complex evolutionary processes where the source, or even the existence of selection for maintaining a function in the genome is often unclear. For example, MGE-driven HGT depends on cell envelope structures and defense systems, but many of these are transferred by MGEs themselves. MGEs can spur periods of intense gene transfer by increasing their own rates of horizontal transmission upon communicating, eavesdropping, or sensing the environment and the host physiology. This may result on high-frequency transfer of host genes unrelated with the MGE. Here, we review how MGEs drive HGT and how their transfer mechanisms, selective pressures, and genomic traits affect gene flow, and therefore adaptation, in microbial populations. The encoding of many adaptive niche-defining microbial traits in MGEs means that intragenomic conflicts and alliances between cells and their MGEs are key to microbial functional diversification.

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