nioella nioella nioella is a genus of bacteria in the family of rhodobacteraceae. nioella scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: rhodobacterales family: rhodobacteraceae genus: nioellarajasabapathy et al. 2015 type species nioella nitratireducens species n. aestuarii n. nitratireducens n. ostreopsis n. sediminis