Novel acetic acid bacteria from cider fermentations: Acetobacter conturbans sp. nov. and Acetobacter fallax sp. nov

Abstract

Strains LMG 1627T, LMG 1636T and LMG 1637 were all isolated from cider fermentations in the 1940s and 1950s. A recent study based on MALDI-TOF MS and dnaK gene sequence analyses suggested they represented novel Acetobacter species. In the present study, we determined the whole-genome sequences of these strains and analysed their phenotypic and chemotaxonomic characteristics. A phylogenomic analysis based on 107 single-copy core genes revealed that they represented a single Acetobacter lineage with Acetobacter aceti , Acetobacter sicerae , Acetobacter musti and Acetobacter oeni , Acetobacter estunensis and with Acetobacter nitrogenifigens as an outgroup to this cluster. OrthoANIu value and dDDH analyses among these and other Acetobacter type strains confirmed that these three strains represented two novel Acetobacter species, which could be differentiated from other closely related type strains of Acetobacter by different phenotypic tests, such as ketogenesis from glycerol. We therefore propose to classify strain LMG 1627T in the novel species Acetobacter conturbans sp. nov., with LMG 1627T (=NCIMB 8945T) as the type strain, and to classify strains LMG 1636T and LMG 1637 in the novel species Acetobacter fallax sp. nov., with LMG 1636T (=NCIMB 8956T) as the type strain.

Desertivirga arenae gen. nov., sp. nov. and Desertivirga brevis sp. nov., isolated from desert soil, and reclassification of Pedobacter xinjiangensis as Desertivirga xinjiangensis comb. nov. and Pedobacter mongoliensis as Paradesertivirga mongoliensis gen.nov., comb. nov.

“…Furthermore, strains SYSU D00823 T , SYSU D00873 T and P. xinjiangensis CCTCC AB 208092 T showed 56.7-57.3 % POCP values with P. mongoliensis KCTC 52859 T . Although a 50 % POCP cut-off value was proposed for defining bacterial genera [23], it has been shown that this universal cut-off is too conservative to be appropriate for circumscribing many bacterial genera [31][32][33]. The detailed paired overall genome relatedness indices (OGRIs) are shown in Table 2.…”

Recent advances of fermented fruits: A review on strains, fermentation strategies, and functional activities

“…Researchers have striving to isolate high-performing acetic acid bacteria from vinegar grains, vinegar mash, and decay sites of fruits. Recently, Acetobacter pasteurianus ( Wu et al, 2018 ), Acetobacter aceti ( Sombolestani et al, 2020 ), Acetobacter rancens ( Zheng, Liu, Zhang, & Wang, 2010 ), and Acetobacter malorum ( Sainz, Mas, & Torija, 2017 ) stand out as the most frequently employed strains in fruit vinegar fermentation. These Acetobacter strains demonstrated the ability to convert alcohol into acetic acid, meanwhile, some volatile aroma components such as organic acids, esters, ketones, and aldehydes were produced, giving fruit vinegar complex aroma and flavor.…”

Aristophania vespae gen. nov., sp. nov., isolated from wasps, is related to Bombella and Oecophyllibacter, isolated from bees and ants

“…To test ketogenesis from glycerol, isolates were cultivated on agar medium containing 2.5 % (w/v) agar and 2 % (w/v) glycerol at 28 °C for 2 h under aerobic conditions. The cultures were then covered with Benedict reagent (17.3 % (w/v) sodium citrate, 10 % (w/v) sodium carbonate, 1.73 % (w/v) copper sulphate pentahydrate) and incubated under the same conditions for another 3 h [57]. The presence of 2-keto- d -gluconic acid and 5-keto- d -gluconic acid was determined in triplicate by HPLC using a Prominence-i separation module (Shimadzu) equipped with an HPX-87H column (Bio-Rad) and a photodiode array detector (Shimadzu).…”