L. sakei has evolved to adapt itself to the
meat environment, harboring the genetic
function that gives it the ability to grow and
survive there. L. sakei seems very well suited
to derive energy from other compounds
that are more abundant in meat. Its adaptation
to meat, an environment rich in amino
acids because of the activity of endogenous
proteases, has caused it to lose biosynthetic
pathways for amino acid synthesis. L. sakei
is therefore auxotrophic for all amino
acids except aspartic and glutamic acid
(Champomier - Verges et al. 2002 ). Amino
acid metabolism can provide an alternative
energy source for L. sakei when glucose
is exhausted, and this affects the sensorial
properties of the sausage, as discussed
later. The genome shows a particularly well -
developed potential for amino acid catabolism, and in addition, L. sakei has the ability
to use purine nucleosides for energy production (a unique property among lactic acid
bacteria).