Some conjugation systems, such as IncF, IncH, and IncI plasmids, transfer DNA efficiently in liquid media, while others, including the IncN, IncM, IncP, and IncW plasmids, achieve higher DNA transfer frequencies on solid media [28]. It is suspected that the ability to transfer DNA in different environmental conditions is related to variation in pilus formation, structure, and stability of cells during the conjugation process.

rigid pili, such as Inc N, P and W, conjugate at rates 2–4 orders of magnitude higher on solid surfaces

flexible pili (e.g. Inc F, H and I), transfer equally well in liquid as in solid surfaces

The mixes were spotted on PBS + 1.5% agar plates and incubated at 37 °C

conjugative plasmids have broad-host ranges23, are resistant to restriction-modification systems24, are easy to engineer with large coding capacities25, and do not require a cellular receptor26 that would provide a facile mechanism for bacterial resistance.

Identification of type IV conjugative systems that are systematically excluded from metagenomic bins

Donor and recipients cells were mixed 1:1 (vol/vol, 0.1 to 1 ml), pelleted (2,000g for 10 min), resuspended in 10–100 µl LB + 300 µM DAP, pipetted onto a LB + 300 µM DAP plate and incubated at 37 °C for 2 h

verbs in conjugation VII

filtered onto a track-etched membrane (pore size: 0.2 µm, Whatman CycloporeTM, UK). Filters were placed on agar-solidified (15 g/l) SW or MC medium

resulting suspension was transferred onto sterile 0,2 μm nitrocellulose filters (Advantec) that were placed over 10% TSB agar media

2 ml of mating suspension was transferred to a sterile 0.22-μm Cyclopore membrane (Whatman) by vacuum filtration (<0.4 mbar)

Transfer of plasmid RP4 during bacterial conjugation requires the plasmid-encoded TraJ protein, which binds to a 19-base pair invert sequence repetition within the transfer origin

oriT mimic, minimally contains a 126-bp region encompassing three overlapping inverted-repeat sequences (IR1-3), at least one copy of an accessory repeat (AR) and a defined relaxase core region

recently documented “relaxase-in trans” mechanism of conjugative mobilization facilitated by conjugative plasmids

Mobilizable plasmids carry only the relaxosomal components oriT, a relaxase gene, and one or more nicking auxiliary proteins

IncP plasmids are considered mobilizing plasmids and may transfer other nonconjugative plasmids into new hosts

The host range for three of the plasmids (pBF1, pB7, and pB9) was further investigated by the GFP method described above

Consequently, the plasmid donor cells do not express gfp

mobilizable plasmids, possess their own transfer origin and encode a relaxase but need the help of a conjugative plasmid for their transfer from a donor to a recipient

We tested a broad range of Enterobacteriaceae conjugative plasmids for their sensitivity to the growth stage of the donors and identified three distinct regulation types.

presence of the donor strain on the surface of the mutant selection plates, prevents the use of these plates for replica plating

Plasmids (IncP/N/W)with 373short and rigid pili only transfer efficiently on solid surfaces, unlike those with longand flexible 374pili (IncF/H/T/J),capable of transferring equally well in liquidand on solid surfaces[35,36]

For English, telling the difference between instantaneous and continuative verbs is easy, because we seldom, if ever, use “be +ing” form for the former. For Japanese, however, the situation is complicated, as ていますcan be used with both kinds of verb.