Mooreia alkaloidigena gen. nov., sp. nov. and Catalinimonas alkaloidigena gen. nov., sp. nov., alkaloid-producing marine bacteria in the proposed families Mooreiaceae fam. nov. and Catalimonadaceae fam. nov. in the phylum Bacteroidetes

Abstract

Bacterial strains CNX-216(T) and CNU-914(T) were isolated from marine sediment samples collected from Palmyra Atoll and off Catalina Island, respectively. Both strains were gram-negative and aerobic and produce deep-orange to pink colonies and alkaloid secondary metabolites. Cells of strain CNX-216(T) were short, non-motile rods, whereas cells of strain CNU-914(T) were short, curved rods with gliding motility. The DNA G+C contents of CNX-216(T) and CNU-914(T) were respectively 57.7 and 44.4 mol%. Strains CNX-216(T) and CNU-914(T) contained MK-7 as the predominant menaquinone and iso-C15 : 0 and C16 : 1ω5c as the major fatty acids. Phylogenetic analyses revealed that both strains belong to the order Cytophagales in the phylum Bacteroidetes. Strain CNX-216(T) exhibited low 16S rRNA gene sequence identity (87.1 %) to the nearest type strain, Cesiribacter roseus 311(T), and formed a well-supported lineage that is outside all currently described families in the order Cytophagales. Strain CNU-914(T) shared 97.6 % 16S rRNA gene sequence identity with 'Porifericola rhodea' N5EA6-3A2B and, together with 'Tunicatimonas pelagia' N5DB8-4 and four uncharacterized marine bacteria isolated as part of this study, formed a lineage that is clearly distinguished from other families in the order Cytophagales. Based on our polyphasic taxonomic characterization, we propose that strains CNX-216(T) and CNU-914(T) represent novel genera and species, for which we propose the names Mooreia alkaloidigena gen. nov., sp. nov. (type strain CNX-216(T) = DSM 25187(T) = KCCM 90102(T)) and Catalinimonas alkaloidigena gen. nov., sp. nov. (type strain CNU-914(T) = DSM 25186(T) = KCCM 90101(T)) within the new families Mooreiaceae fam. nov. and Catalimonadaceae fam. nov.

Fig. 1.

Neighbour-joining phylogenetic tree based on 16S rRNA gene sequences (1335 bp), showing relationships between strains CNX-216^T and CNU-914^T and representatives from related families in the phylum Bacteroidetes. Bootstrap values ≥50 % (from 1000 replicates) from neighbour-joining/maximum-likelihood analyses are shown at nodes. Filled circles indicate nodes that were observed with both neighbour-joining and maximum-likelihood algorithms. Type strains outside of the Cytophagales were used as an outgroup. Bar, 0.02 substitutions per nucleotide position.