Weissella

Weiss.el'la. N.L. fem. dim. n. Weissella, genus named after Norbert Weiss, a German microbiologist known for his many research contributions to the taxonomy of the lactic acid bacteria. Bacillota / Bacilli / Lactobacillales / Lactobacillaceae / Weissella Bacteria belonging to the genus Weissella are Gram-stain-positive, catalase-negative, nonmotile and nonspore-forming. The genus Weissella presently contains 23 species. Weissellas are facultatively aerobic, chemoorganotrophs, and ferment hexose sugars via the hexose-monophosphate and phosphoketolase pathways to lactic acid, CO2, ethanol and/or acetate. Either dl or d(−) lactate are produced, depending on the species. Weissellas can grow at 15°C and some species grow up to 42–45°C. The peptidoglycan typically contains lysine as diamino acid. The major fatty acids present in most Weissella species are C16:0 saturated and C18:1 ω9c unsaturated fatty acids. Weissellas occur in meats, fermented fish, and plant products such as beans, cacao, and cassava, in milk, human body sites as well as insects. The DNA mol% G + C contents of Weissella-type species ranges from 35.5 to 45.0%, with a mean of 39.9% and a median of 39.5 mol%. The genome sizes range from 1.33 to 2.49 Mb, with a mean of 1.85 Mb and a median of 1,808,244 bp. Some Weissella spp. have high biotechnological potential as starter cultures, probiotics, or postbiotics due to production of valuable compounds such as exopolysaccharides, novel nondigestible oligosaccharides, molecules with bio-functional activity, and technological properties. DNA G + C content (mol%): 37–47. Type species: Weissella viridescens Collins et al. 1993, VL49 (basonym: Lactobacillus viridescens Niven and Evans 1957AL).