Lactobacillus sicerae sp. nov., a lactic acid bacterium isolated from Spanish natural cider.

Strains CUPV261T and CUPV262 were isolated from ropy natural ciders of the Basque Country, Spain, in 2007. Cells are Gram-stain positive, non-spore-forming, motile rods, facultative anaerobes and catalase-negative. The strains are obligately homofermentative (final product dl-lactate) and produce exopolysaccharides from sucrose. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the highest similarity to both isolates corresponded to the type strain of Lactobacillus vini (99.1 %), followed by Lactobacillus satsumensis (96.4 %), and Lactobacillus oeni (96.2 %), and for all other established species, 16S rRNA gene sequence similarities were below 96 %. The species delineation of strains CUPV261T and CUPV262 was evaluated through RAPD fingerprinting. In addition, a random partial genome pyrosequencing approach was performed on strain CUPV261T in order to compare it with the genome sequence of Lactobacillus vini DSM 20605T and calculate indexes of average nucleotide identity (ANI) between them. Results permit the conclusion that strains CUPV261T and CUPV262 represent a novel species of the genus Lactobacillus , for which the name Lactobacillus sicerae sp. nov. is proposed. The type strain is CUPV261T ( = CECT 8227T = KCTC 21012T).