Hyunsoonleella sp. strain J2K-J805 is a yellow-pigmented marine bacterium isolated from coastal seawater collected at Jongdal-ri, Jeju Island, Republic of Korea. Here, we report the single-contig genome sequence of strain J2K-J805 obtained using Oxford Nanopore sequencing and de novo assembly. The genome is 3,825,400 bp long with a DNA G + C content of 34.9 mol%, 100% breadth of coverage, a mean depth of 50×, 99.98% completeness, and 0.01% contamination. Annotation predicted 3285 coding sequences, 37 tRNAs, 6 rRNAs, 24 ncRNAs, 16 pseudogenes, and 3 CRISPR arrays. Whole-genome comparisons indicated that strain J2K-J805 is most closely related to Hyunsoonleella flava T58T (OrthoANIu 87.72%; dDDH 34.5%), with values below the species-delineation thresholds. Screening of public metagenomes recovered J2K-J805-associated k-mers mainly from marine, aquatic, and sediment datasets, whereas no species representative in the screened GTDB collection met the species-level cutoff. The genome encoded a co-localized cluster of carotenoid biosynthesis genes (crtI, crtB, crtZ, and crtY), the IPP isomerase gene idi, and a near-complete mevalonate (MVA) pathway, consistent with a putative pathway for zeaxanthin biosynthesis. This genome expands the genomic resources available for the genus Hyunsoonleella and provides a foundation for comparative studies of carotenoid biosynthesis in marine Flavobacteriaceae.
Juyeong An, M. Taj, Jong Woo Hyeon et al.· Marine Genomics· 0 citations
A Gram-stain-negative, strictly aerobic, yellow-pigmented, non-motile, rod-shaped rod-shaped bacterium, designated J2K-J805T, was isolated from coastal seawater of Jeju Island, Republic of Korea. Strain J2K-J805T grew at 15–37°C (optimum, 30°C), pH 6.0–8.0 (optimum, pH 7.0–7.5) and in the presence of 1–4% (w/v) NaCl (optimum, 2–3%) and was catalase-positive and oxidase-negative. The strain showed the highest 16S rRNA gene sequence similarity to Hyunsoonleella flava T58T (98.4%). Phylogenetic and phylogenomic analyses based on the 16S rRNA gene and whole-genome sequences placed strain J2K-J805T within the genus Hyunsoonleella as a distinct lineage. The OrthoANIu and digital DNA-DNA hybridization values between strain J2K-J805T and H. flava T58T were 87.7 and 34.5%, respectively, both below their respective thresholds for species delineation. The genome size and DNA G+C content were 3,825,400 bp and 34.9 mol%, respectively. The predominant respiratory quinone was MK-6, and the major cellular fatty acids were iso-C15:1 G, iso-C15:0 and iso-C17:0 3-OH. The polar lipid profile comprised phosphatidylethanolamine, three unidentified aminolipids, two unidentified glycolipids and five unidentified lipids. High-performance liquid chromatography with photodiode-array detection identified the major yellow pigment as zeaxanthin, and the genome contained the carotenoid biosynthesis genes crtB, crtI, crtY and crtZ together with genes for isoprenoid precursor supply. On the basis of these polyphasic data, strain J2K-J805T represents a novel species, for which the name Hyunsoonleella zeaxanthinifaciens sp. nov. is proposed. The type strain is J2K-J805T (= KCTC 102498T = JCM 38469T).
Juyeong An, Jong Woo Hyeon, M. Taj et al.· Journal of Microbiology and...· 0 citations
