Genomic Analysis of an Excellent Wine-Making Strain SD-2a.

is an important microorganism in wine-making-related engineering, and it improves wine quality and stability through malolactic fermentation. Although the genomes of more than 200 strains have been sequenced, only a few include completed genome maps. Here, the genome sequence of SD-2a, isolated from Shandong, China, has been determined. It is a fully assembled genome sequence of this strain. The complete genome is 1,989,703 bp with a G+C content of 37.8% without a plasmid. The genome includes almost all the essential genes involved in central metabolic pathways and the stress genes reported in other strains. Some natural competence-related genes, like EA, EC, FA, G operon, and FC, suggest that SD-2a may have natural transformation potential. A comparative genomics analysis revealed 730 gene clusters in SD-2a homologous to those in four other lactic acid bacteria species ( PSU-1, CRBO-11381, UNQLp11, and KCCM40703). A collinearity analysis showed poor collinearity between SD-2a and PSU-1, indicating great differences in their evolutionary histories. The results provide general knowledge of SD-2a and lay the foundation for specific gene function analyses.