Novosphingobium album sp. nov., Novosphingobium organovorum sp. nov. and Novosphingobium mangrovi sp. nov. with the organophosphorus pesticides degrading ability isolated from mangrove sediments

Abstract

Members of the genus Novosphingobium were frequently isolated from polluted environments and possess great bioremediation potential. Here, three species, designated B2637 T , B2580 T and B1949 T , were isolated from mangrove sediments and might represent novel species in the genus Novosphingobium based on a polyphasic taxonomy study. Phylogenomic analysis revealed that strains B2580 T , B1949 T and B2637 T clustered with Novosphingobium naphthalenivorans NBRC 102051 T , ‘ N. profundi ’ F72 and N. decolorationis 502str22 T , respectively. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between isolates and their closely related species were less than 94 and 54 %, respectively, all below the threshold of species discrimination. The sizes of the genomes of isolates B2580 T , B2637 T and B1949 T ranged from 4.4 to 4.6 Mb, containing 63.3–66.4 % G+C content. Analysis of their genomic sequences identified genes related to pesticide degradation, heavy-metal resistance, nitrogen fixation, antibiotic resistance and sulphur metabolism, revealing the biotechnology potential of these isolates. Except for B2637 T , B1949 T and B2580 T were able to grow in the presence of quinalphos. Results from these polyphasic taxonomic analyses support the affiliation of these strains to three novel species within the genus Novosphingobium , for which we propose the name Novosphingobium album sp. nov. B2580 T (=KCTC 72967 T =MCCC 1K04555 T ), Novosphingobium organovorum sp. nov. B1949 T (=KCTC 92158 T =MCCC 1K03763 T ) and Novosphingobium mangrovi sp. nov. B2637 T (KCTC 72969 T =MCCC 1K04460 T ).