Evolutionary analysis and quality assessment of -carbonic anhydrase sequences from environmental microbiome

Carbonic anhydrase (CA) is one of the most vital enzymes in living cells. This study has been performed due to the significance of this metalloenzyme for life and the novelty of some CA families like zeta-CA to evaluate evolutionary processes and quality check their sequences. In this study, bioinformatics methods revealed the presence of zeta-CA in some eukaryotic and prokaryotic microorganisms. Notably, it has not been previously reported in prokaryotes. The coexistence of beta- and zeta-CAs in some microorganisms is also a novel finding as well. Also, our analysis identified several CA proteins with 6-14 amino acid intervals between histidine and cysteine in the second highly conserved motif, which can be classified as the novel zeta-CA subfamily members that emerged under the Zn deficiency of aquatic ecosystems and selection pressure in these environments. There is also a possibility that the achieved results are rooted in the contamination of samples from the environmental microbiome genome with genomes of diatom species and the occurrence of errors was observed in the DNA sequencing outcomes. Combining of all results from evolutionary analysis to quality control of zeta-CA DNA sequences is the incentive motivation to explore more the hidden aspects of zeta-CAs.