Genomic and biochemical investigations in the biomineralizing potential of an isolated marine ureolytic Bacillus sp. N₉

Abstract

Microbially Induced Calcium Carbonate Precipitation (MICP) plays a significant role in coastal soil stabilization and erosion prevention. In the present study, the biomineralizing potential of a newly isolated Bacillus sp. N₉ was investigated through MICP. The isolated Bacillus sp. N₉ induced calcium carbonate (CaCO₃) precipitation in broth, agar, and real beach rock was evaluated by X-ray Fluorescence, Scanning Electron Microscopy, and X-ray Diffraction. The visual appearance of calcites as white crystals on the rock and the sealing of cracks in the beach sand cubes confirmed the CaCO₃ precipitation by the isolated strain. The pH changes, soluble calcium (Ca²⁺) concentration levels and urease activity during the growth of the isolated Bacillus sp. N₉ were studied. High urease activity was observed, resulting in an increased production of carbonate (CO₃²⁻) ions, which in turn promoted a higher rate of CaCO₃ precipitation. Further, the assembly of the 3.27 Mb genome of the isolated Bacillus sp. N₉ was evaluated using Nanopore sequencing technology, and various extracellular proteins, including urease, were identified. The gene annotation through PROKKA and RAST predicted 6700 and 7317 protein-coding sequences. The pathway annotation analysis through gene ontology, KEGG, and COG inferred the presence of genes in proteolytic characteristics, carbohydrate metabolism, and amino acid derivatives. The present study provides valuable insights into the isolated native Bacillus sp. N₉, demonstrating its potential to produce high urease activity and calcite precipitation through combined genomics and in vitro techniques.