Comparative genomic analyses reveal carbohydrates-rich environment adaptability of Lentilactobacillus laojiaonis sp. nov. IM3328

Lentilactobacillus laojiaonis sp. nov. IM3328 was isolated from a mud cellar which has been continuously used for the fermentation of Chinese strong-flavour baijiu for over hundreds of years. Its 1.24-Mb genome comprising a single chromosome was the smallest genome for a lactobacilli strain sequenced to date. The genome of strain IM3328 was compared with the sourdough-oriented Fructilactobacillus sanfranciscensis TMW 1.1304 (1.38-Mb) and the Bombus gut-oriented Apilactobacillus bombintestini sp. nov. BHWM-4 (1.29-Mb), two lactobacilli strains with genome size slightly larger than that of strain IM3328. Comparative genomic analyses reveal that strain IM3328, despite having the smallest genome, is capable of metabolize hexose and pentose efficiently, which coincides with the fact that the strain resides in a habitat with abundant carbohydrates. These findings imply that the metabolic capabilities and traits of strain IM3328 directly related to its survival or competitiveness in a biomass-rich habitat.