Genomic and Metabolic Characterization of a Potentially Novel <i>Paenibacillus</i> Species Isolated as a Laboratory Contaminant Growing on Medium Supporting Cotton Tissue Culture

Paenibacillus sp. TAB_01, an isolate recovered from cotton tissue culture plates and a potential novel species within the genus Paenibacillus was sequenced using Oxford Nanopore technology. The genome was 7.46 Mb with a G + C content of 52.14%, comprising 7353 total genes, including 6553 coding DNA sequences (CDS) and 159 RNA sequences, including 109 tRNA genes, 46 rRNA genes, and two CRISPR regions. In addition, the genome contains 6553 protein sequences. The results of the digital DNA-DNA hybridization analysis showed that the genome of Paenibacillus sp. TAB_01 shared 22.2% similarity with its closest genomic neighbor, Paenibacillus rigui. OrthoANIu analysis using USEARCH revealed 78% similarity, while ANI analysis using BLAST indicated 76.8% similarity between the two genomes. The MLSA-based phylogenetic tree showed that Paenibacillus sp. TAB_01 clustered within the Paenibacillus genus but formed a separate lineage. Furthermore, Paenibacillus sp. TAB_01 exhibited strong plant growth-promoting potential by producing 112.4 µg/mL of ammonium, 65.6 µg/mL of soluble inorganic phosphate, and 19.5 ng/mL of indole-3-acetic acid (IAA). These metabolites were quantified using colorimetric assays with high linearity (R² > 0.95). Genomic and metabolic properties indicate that Paenibacillus sp. TAB_01 represents a potentially novel species within the genus Paenibacillus, clearly distinct from its closest relatives.