Chryseobacterium palustre sp. nov. and Chryseobacterium humi sp. nov., isolated from industrially contaminated sediments

Abstract

Two Gram-staining-negative bacterial strains, designated 3A10T and ECP37T, were isolated from sediment samples collected from an industrially contaminated site in northern Portugal. These two organisms were rod-shaped, non-motile, aerobic, catalase- and oxidase-positive and formed yellow colonies. The predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 1 ω9c and iso-C17 : 0 3-OH. The G+C content of the DNA of strains 3A10T and ECP37T was 43 and 34 mol%, respectively. The major isoprenoid quinone of the two strains was MK-6. 16S rRNA gene sequence analysis revealed that strains 3A10T and ECP37T were members of the family Flavobacteriaceae and were related phylogenetically to the genus Chryseobacterium. Strain 3A10T showed 16S rRNA gene sequence similarity values of 97.2 and 96.6 % to the type strains of Chryseobacterium antarcticum and Chryseobacterium jeonii, respectively; strain ECP37T showed 97.3 % similarity to the type strain of Chryseobacterium marinum. DNA–DNA hybridization experiments revealed levels of genomic relatedness of <70 % between strains 3A10T and ECP37T and between these two strains and the type strains of C. marinum, C. antarcticum and C. jeonii, justifying their classification as representing two novel species of the genus Chryseobacterium. The names proposed for these organisms are Chryseobacterium palustre sp. nov. (type strain 3A10T =LMG 24685T =NBRC 104928T) and Chryseobacterium humi sp. nov. (type strain ECP37T =LMG 24684T =NBRC 104927T).