The genome was assembled using Unicycler with default settings for both MinION and Illumina data. A unique bin was generated using MetaWRAP version 1.2.1 and taxonomically annotated using GTDB-Tk version 2.1.1 with the Genome Taxonomy Database (r207). Plasmid sequences were identified using geNomad end-to-end function. The GC mol% content was calculated using Seqkit fx2tab function. Gene prediction was performed using Prodigal version 2.6.3 and annotation performed using Diamond BLASTp v0.8.36(e-value <10−5) with the National Center for Biotechnology
Information (NCBI) nr database release 244. Genome quality was assessed using CheckM, estimating 99.1% completeness and 0.34% contamination, and GToTree, detecting 100% of expected single-copy genes with 0% redundancy. To investigate the metabolic potential of NHB1, a curated protein dataset of the Nitrobacter hamburgensis X14 genome was downloaded from NCBI. Protein sequences were compared using Diamond BLASTp v0.8.36 (e-value <10−5) to identify homologous metabolic genes. Genomic relatedness among different Nitrobacter strains was evaluated by calculating both Average Nucleotide Identity (ANI) and Average Amino Acid Identity (AAI) using FastANI v1.33 and FastAAI, respectively.
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