Genetics and Biotechnology of Lactic Acid Bacteria

Lactic acid bacteria is used throughout the world in the manufacture of a wide variety of fermented milk products. Fermentations by lactic acid bacteria determine important qualities such as taste, shelf-life, food value and rheological properties. Their prime functions include the conversion of lactose to lactate, the release of amino acids and peptides through proteolyptic breakdown of milk proteins, and the production of the aroma compound diacetyl from citrate. New methods of food production require fast, time-controlled and reliable manufacture and these new conditions have placed traditional starter culture practice under strong pressure. With the greater commercial significance of these processes there has been recently a dramatic increase of interest in the genetic, microbiological and biochemical properties of lactic acid bacteria. This book concentrates upon the genetic aspects of the subject, and hence through application, the biotechnology. The genetics form the most important and fastest moving aspect of current activity.

Natural transfer systems and transposition. Host vector systems and heterologous gene expression in lactococcus. Genetic engineering in lactobacillus, leuconostoc and streptococcus. Carbohydrate catabolism. Proteolyptic systems. Bacteriophage and bacteriophage resistance. Antimicrobials.