Properties of a Good Host

Change that a normal cell undergoes as it becomes malignant; also, permanent, heritable alteration in a cell resulting from the uptake and incorporation of foreign DNA into genome.

In organisms like bacteria and other microbes, (or) even in higher plants, the uptake of genes by cells is often described by the term “Transformation”. However in animals this term has been replaced by the term “transfection”, because the term “Transformation” in animal cell culture is used to describe phenotypic alteration of cells.

Properties of a Good Host

A good host should have the following features:

(1) is easy to transform,

(2) Supports the replication of recombinant DNA,

(3) is free from elements that interfere with replication of recombinant DNA,

(4) Lacks active restriction enzymes, e.g., E. coli K12 substrain HB 101,

(5) does not have methylases since these enzymes would methylate the replicated recombinant DNA which, as a result, would become resistant to useful restriction enzymes, and

(6) is deficient in normal recombination function so that the DNA insert is not altered by recombination events.