. "Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) is a representative of the group of lactic acid-producing bacteria, mainly known for its worldwide application in yogurt production. The genome sequence of this bacterium has been determined and shows the signs of ongoing specialization, with a substantial number of pseudogenes and incomplete metabolic pathways and relatively few regulatory functions. Several unique features of the L. bulgaricus genome support the hypothesis that the genome is in a phase of rapid evolution. (i) Exceptionally high numbers of rRNA and tRNA genes with regard to genome size may indicate that the L. bulgaricus genome has known a recent phase of important size reduction, in agreement with the observed high frequency of gene inactivation and elimination; (ii) a much higher GC content at codon position 3 than expected on the basis of the overall GC content suggests that the composition of the genome is evolving toward a higher GC content; and (iii) the presence of a 47.5-kbp inverted repeat in the replication termination region, an extremely rare feature in bacterial genomes, may be interpreted as a transient stage in genome evolution. The results indicate the adaptation of L. bulgaricus from a plant-associated habitat to the stable protein and lactose-rich milk environment through the loss of superfluous functions and protocooperation with Streptococcus thermophilus." . . "Proc. Natl. Acad. Sci. U.S.A." . "Ehrlich S.D." . "Nicolas P." . "Robert C." . "Weissenbach J." . "Bolotin A." . "van de Guchte M." . "Maguin E." . "Bessieres P." . "Dervyn R." . "Barbe V." . "Grimaldi C." . "Gibrat J.-F." . "Mangenot S." . "Walunas T." . "Oztas S." . "Couloux A." . "Bossy R." . "Loux V." . "Penaud S." . "Bryson K." . "Batto J.-M." . "2006"^^ . "9274-9279" . "The complete genome sequence of Lactobacillus bulgaricus reveals extensive and ongoing reductive evolution." . "103" . "doi:10.1073/pnas.0603024103" .