L-Growth Medium

Principle and Interpretation

L-Growth Medium is a nutritionally enriched medium for the cultivation and maintenance of recombinant strains of E. coli for genetic and molecular biology studies for purposes of strain maintenance, cloning, plasmid propagation, and protein expression (1). This nutritionally rich medium was originally developed by Miller for cultivation and maintenance of E. coli cells in molecular biology (2).

All nutritional requirements of E. coli strains are provided by L-Growth Medium. Peptides and amino acids are abundantly present in Tryptone. Yeast extract is a rich source of amino acids, vitamins, nucleotides and carbohydrates. These nutritional elements support a luxurious growth of E. coli cells. The concentration of NaCl in this media is low compared to both LB Miller and LB Lennox formulations, respectively 10% and 5% of the NaCl concentration is present in both formulations. These variations in Sodium chloride content make it possible to select the optimal salt concentration for a specific strain.