Naturally Transformable Acinetobacter sp. Strain ADP1 Belongs to the Newly Described Species Acinetobacter baylyi

Abstract

Genotypic and phenotypic analyses were carried out to clarify the taxonomic position of the naturally transformable Acinetobacter sp. strain ADP1. Transfer tDNA-PCR fingerprinting, 16S rRNA gene sequence analysis, and selective restriction fragment amplification (amplified fragment length polymorphism analysis) indicate that strain ADP1 and a second transformable strain, designated 93A2, are members of the newly described species Acinetobacter baylyi. Transformation assays demonstrate that the A. baylyi type strain B2(T) and two other originally identified members of the species (C5 and A7) also have the ability to undergo natural transformation at high frequencies, confirming that these five strains belong to a separate species of the genus Acinetobacter, characterized by the high transformability of its strains that have been cultured thus far.

Bacterial recombination promotes the evolution of multi-drug-resistance in functionally diverse populations

“…This bacterium has high competency for natural transformation [32] and occasionally causes antibioticresistant infections in humans [33]. No plasmids or viruses are present in our experimental strains and therefore the only mechanism of recombination is transformation.…”

Horizontal gene transfer between bacteria

“…Recently, the naturally transformable Acinetobacter sp. ADP1 strain and its derivative BD413 were shown to belong to the newly described species Acinetobacter baylyi (Vaneechoutte et al, 2006). This strain can be transformed efficiently with DNA of different sources.…”

“…The exogenous isolation of MGEs, which was originally used to retrieve plasmids from river epilithon (Bale et al, 1988), was also successfully used to capture MGEs from soil or phytosphere communities (Smalla and Sobecky, 2002). Recipients functioning as a genetic sink, and introduced under laboratory or in situ conditions, have acquired MGEs conferring selectable traits such as mercury or antibiotic resistance from the bacterial fraction of bulk or rhizosphere soil (Drønen et al, 1998;Heuer and Smalla, 2007;Heuer et al, 2002;van Overbeek et al, 2002). Mercury resistance was used as an effective selective marker to exogenously isolate self-transferable plasmids from the phytosphere of different crops in Gram-negative recipients (Lilley and Bailey, 1997;Lilley et al 1994;Schneiker et al, 2001;Smit et al, 1998) or from mercury-polluted soils (Drønen et al, 1998).…”

“…Capturing degradative genes resident on MGEs has also been successfully demonstrated from soils treated with 2,4-D, but not from untreated controls (Top et al, 1995;. Self-transferable plasmids conferring resistance towards a range of antibiotics were captured from animal manures used for soil fertilization (Heuer and Smalla, 2007;Heuer et al 2002;Smalla et al, 2000;van Overbeek et al, 2002). Mobilizing plasmids were isolated by Van Elsas et al (1998), when bacterial communities obtained from the rhizosphere of young wheat plants served as donor in a tri-parental mating.…”

Assessment of transformability of bacteria associated with tomato and potato plants

“…The state of competence leading to natural transforma-bility is commonly related to the presence of competence genes, like the com genes present in Thermus thermophilus and Acinetobacter baylyi (Friedrich et al, 2001 and. The naturally transformable strain A. baylyi ADP1 (ADP1; also known as A. baylyi BD413, see Vaneechoutte et al, 2006) has been demonstrated to develop genetic competence and to be transformable in soil (Ceccherini et al, 2003;Kay et al, 2003;Nielsen et al, 2000b). Transformants successfully occurred after treatment with DNA homologous to recipient genomes (Nielsen et al, 2000a).…”