Methods and constructs for improving conjugation efficiency

A method for increasing conjugation efficiency of a basic conjugative element which comprises an origin of transfer (oriT) sequence defining a leading region sequence, a T-strand, and a T-strand complement,

• the method comprising inserting into the leading region sequence of the basic conjugative element an anti-defense nucleotide sequence comprising a sequence encoding at least one anti-defense gene, thereby generating an improved conjugative element,
• wherein:
• following the inserting, the at least one anti-defense gene is encoded on the T-strand complement within about 35 kb from the oriT and/or within about 30 open reading frames (ORFs) closest to the oriT;
• and
• the conjugation efficiency of the improved conjugative element is increased compared to the conjugation efficiency of the basic conjugative element.

A method for modulating recipient bacteria, the method comprising contacting the recipient bacteria with donor bacteria comprising a conjugative element, which comprises:

• an origin of transfer (oriT) sequence defining a leading region sequence, a T-strand, and a T-strand complement;
• at least one anti-defense gene encoded on the T-strand complement, within the leading region sequence, within about 35 kb from the oriT and/or within about 30 open reading frames (ORFs) closest to the oriT;
• and
• a cargo gene capable of modulating the recipient bacteria,
• wherein the recipient bacteria express a defense gene product which is inhibited by a product of the at least one anti-defense gene.