Vogesella denitrificans sp. nov., Vogesella limnetica sp. nov., Vogesella montanilacustris sp. nov., Vogesella oligotrophica sp. nov. and Vogesella rivulicola sp. nov., isolated from the freshwater environments

Background Vogesella strains, which belong to the family Chromobacteriaceae , have attracted considerable attention due to their ability to synthesize indigoidine. However, due to the limited number of available strains, research on the ecological functions of this genus remains insufficient. Results In the last few years, 18 Vogesella strains were isolated from the freshwater environments and 8 of them have been reported in 2023. The remaining 10 Vogesella strains (Dicai11, DSH15, FXH17, FXH30, FXH49, Huaxi11, Huaxi14, Ji36, YLH38 and YLH41) were subjected to detailed comparative analysis with other Vogesella strains in this study. Comparisons based on the 16S rRNA gene sequences showed that strains Dicai11, FXH30, Huaxi14 and Ji36 show the highest 16S rRNA gene sequence similarities of 98.9, 99.2, 99.2 and 98.3% to Vogesella indigofera DSM 3303 ^T , respectively. Strains YLH38 and YLH41 took Vogesella perlucida DS-28 ^T as their closest neighbor. Strains DSH15, FXH17, FXH49 and Huaxi11 exhibited maximum 16S rRNA gene sequence similarities greater than 99.5% to Vogesella mureinivorans 389 ^T , Vogesella lacus GR13 ^T , Vogesella urethralis YM-1 ^T and Vogesella margarita LYT5W ^T , respectively. The ANI and AAI analyses further showed that strains FXH30 and Huaxi14 should belong to the species V. indigofera , and strains FXH49, Huaxi11 and YLH41 should belong to the species V. urethralis , V. margarita and V. perlucida , respectively. The ANI values between each of strains Dicai11, DSH15, FXH17, Ji36 and YLH38 and each of the other tested strains were all less than 94.4%, indicating that each of these five strains should represent an independent novel species of genus Vogesella , for which the names Vogesella denitrificans sp. nov. (Dicai11 ^T =GDMCC 1.6233 ^T =KCTC 18482 ^T ), Vogesella rivulicola sp. nov. (DSH15 ^T =GDMCC 1.6232 ^T =KCTC 18472 ^T ), Vogesella oligotrophica sp. nov. (FXH17 ^T =GDMCC 1.6237 ^T =KCTC 18476 ^T ), Vogesella montanilacustris sp. nov. (Ji36 ^T =GDMCC 1.6234 ^T =KCTC 18473 ^T ) and Vogesella limnetica sp. nov. (YLH38 ^T =GDMCC 1.6230 ^T =KCTC 18470 ^T ) are proposed, respectively. The phylogenomic analysis revealed that the Vogesella strains could be divided into 5 distinct clades. Strain FXH17 represented an independent clade. Strains Dicai11 and Ji36 isolated from the alpine lakes also represented an independent clade. Strains DSH15 and YLH38 formed a clade with V. urethralis , Vogesella aquatica , V. perlucida and V. mureinivorans . Comparative genomic analyses showed that not each of Vogesella strains could synthesize indigoidine and it seemed that multiple pathways are responsible for producing indigoidine. Obvious genetic differences were also present among Vogesella strains, especially in the aspects of nitrogen and phosphorus cycling. Most Vogesella strains had no complete denitrification pathway and lacked the nitrous oxide reductase. Only strain Dicai11 had the complete phosphonate transport and metabolism systems, enabling it to adapt to the phosphorus-limited habitats of alpine lakes. Conclusions Taken together, our study broadens the knowledge about the ecological functions of Vogesella strains.