Microbial carbonation, a process where microbes contribute to carbonate mineralization, has great potential for advancing carbon sequestration and achieving net-zero emissions. Central to this process is the enzyme carbonic anhydrase. However, realizing the full potential of microbial carbonation requires a comprehensive understanding of the diverse microorganisms harboring these critical genes.
Current research has largely focused on aerobic and easily culturable species, which may not be optimal for environments with high CO2 concentrations. This study addresses the need to identify microbes that possess carbonic anhydrase genes and thrive in CO2-rich environments, offering a broader scope for bioprospecting.
Using the NCBI database, we searched for accession numbers associated with carbonic anhydrase genes and extracted relevant information, including taxonomy and gene source, and then downloaded the relevant sequences from the GeneBank database. We then analysed the presence and distribution of carbonic anhydrase genes across all bacterial and archaeal phyla, classes, and families. From 945 bacterial and 108 archaeal families, the gene is present in 550 bacterial families and only 28 archaeal families. The primary sources of these genes were from contigs and whole genomes. Notably, 73.7% of the downloaded genes had an average nucleotide length of 700 to 1000 base pairs.
This systematic assessment of carbonic anhydrase genes in prokaryotes provides valuable insights into microbial carbonation and its potential role in mitigating atmospheric CO2. These findings pave the way for future efforts in utilizing microbial processes for carbon sequestration.