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

Two Gram-staining-negative bacterial strains, designated 3A10(T) and ECP37(T), 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-C(15 : 0), anteiso-C(15 : 0), iso-C(17 : 1)omega9c and iso-C(17 : 0) 3-OH. The G+C content of the DNA of strains 3A10(T) and ECP37(T) 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 3A10(T) and ECP37(T) were members of the family Flavobacteriaceae and were related phylogenetically to the genus Chryseobacterium. Strain 3A10(T) 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 ECP37(T) showed 97.3 % similarity to the type strain of Chryseobacterium marinum. DNA-DNA hybridization experiments revealed levels of genomic relatedness of <70 % between strains 3A10(T) and ECP37(T) 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 3A10(T) =LMG 24685(T) =NBRC 104928(T)) and Chryseobacterium humi sp. nov. (type strain ECP37(T) =LMG 24684(T) =NBRC 104927(T)).