A Gram-stain positive, rod-shaped, non-spore-forming strain (WDC04(T)), which may be associated with late gas production in cheese, was isolated from aged Cheddar cheese following incubation on MRS agar (pH 5.2) at 6 degrees C for 35 days. Strain WDC04(T) had 97 % 16S rRNA gene sequence similarity with Lactobacillus hokkaidonensis DSM 26202(T), Lactobacillus oligofermentans 533, 'Lactobacillus danicus'9M3, Lactobacillus suebicus CCUG 32233(T) and Lactobacillus vaccinostercus DSM 20634(T). API 50 CH carbohydrate fermentation panels indicated strain WDC04(T) could only utilize one of the 50 substrates tested, ribose, although it does slowly utilize galactose. In the API ZYM system, strain WDC04(T) was positive for leucine arylamidase, valine arylamidase, cysteine arylamidase (weakly), naphthol-AS-BI-phosphohydrolase and beta-galactosidase activities. Total genomic DNA was sequenced from strain WDC04(T) using a whole-genome shotgun strategy on a 454 GS Titanium pyrosequencer. The sequence was assembled into a 1.90 Mbp draft genome consisting of 105 contigs with preliminary genome annotation performed using the RAST algorithm (rast.nmpdr.org). Genome analysis confirmed the pentose phosphate pathway for ribose metabolism as well as galactose, N-acetylglucosamine, and glycerol fermentation pathways. Genomic analysis places strain WDC04(T) in the obligately heterofermentative group of lactobacilli and metabolic results confirm this conclusion. The result of genome sequencing, along with 16S rRNA gene sequence analysis, indicates WDC04(T) represents a novel species of the genus Lactobacillus, for which the name Lactobacillus wasatchensis sp. nov. is proposed. The type strain is WDC04(T) (=DSM 29958(T)=LMG 28678(T)).