Marinomonas alcarazii sp. nov., M. rhizomae sp. nov., M. foliarum sp. nov., M. posidonica sp. nov. and M. aquiplantarum sp. nov., isolated from the microbiota of the seagrass Posidonia oceanica

Abstract

Five novel Gram-reaction-negative aerobic marine bacterial strains with DNA G+C contents <50 mol% were isolated from the seagrass Posidonia oceanica. 16S rRNA sequence analysis indicated that they belonged to the genus Marinomonas. Major fatty acid compositions, comprising C10 : 0 3-OH, C16 : 0, C16 : 1ω7c and C18 : 1ω7c, supported the affiliation of these strains to the genus Marinomonas. Strains IVIA-Po-14bT, IVIA-Po-145T and IVIA-Po-155T were closely related to Marinomonas pontica 46-16T, according to phylogenetic analysis. However, DNA–DNA hybridization values <35 % among these strains revealed that they represented different species. Further differences in the phenotypes and minor fatty acid compositions were also found among the strains. Another two strains, designated IVIA-Po-181T and IVIA-Po-159T, were found to be closely related to M. dokdonensis DSW10-10T but DNA–DNA relatedness levels <40 % in pairwise comparisons, as well as some additional differences in phenotypes and fatty acid compositions supported the creation of two novel species. Accordingly, strains IVIA-Po-14bT ( = CECT 7730T  = NCIMB 14671T), IVIA-Po-145T ( = CECT 7377T  = NCIMB 14431T), IVIA-Po-155T ( = CECT 7731T  = NCIMB 14672T), IVIA-Po-181T ( = CECT 7376T  = NCIMB 14433T) and IVIA-Po-159T ( = CECT 7732T  = NCIMB 14673T) represent novel species, for which the names Marinomonas alcarazii sp. nov., Marinomonas rhizomae sp. nov., Marinomonas foliarum sp. nov., Marinomonas posidonica sp. nov. and Marinomonas aquiplantarum sp. nov. are proposed, respectively.