Method for the production of a dairy food product and a method for gene transfer by conjugation

A dairy bacterial strain with clumping and/or chaining properties when cultured under liquid conditions, wherein the clumping property results in clumps of at least 20 bacteria per average clump, and wherein the chaining property results in chains of at least 8 bacteria per average chain, and wherein the strain comprises a pilin gene cluster having a nucleotide sequence that has at least 50% sequence identity with SEQ ID NO:

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