An LPS-dephosphorylating alkaline phosphatase of PhoA family from the marine bacterium Cobetia amphilecti KMM 296 and multiplicity of alkaline phosphatase families in Cobetia spp.

A highly active alkaline phosphatase (ALP) from the mollusk strain of the marine bacterium Cobetia amphilecti KMM 296 (CmAP) was found to remove phosphorus from the Escherichia coli lipopolysaccharides (LPS). Phylogenetic analysis of the amino acid sequences of ALPs found in 36 available Cobetia genomes revealed that CmAP and its homologues from nine strains clustered together with the human and squid LPS-detoxifying enzymes. Each strain of the genus Cobetia has a variety of ALPs mostly of the PhoD and PhoX families. The PhoA gene encoding for the CmAP-like ALP is characteristic for the subspecies C. amphilecti, with a complete set of four ALP families, including PafA and two PhoD structures (5 genes). However, a single strain of the species Cobetia crustatorum JO1T from fermented shrimp, phylogenetically distant from C. amphilecti and C. marina, among four ALPs contains a CmAP homologue carrying an inactive mutation. Apparently, the multiplicity of ALPs in bacteria of the genus Cobetia is a trait of incredible adaptation to a phosphorus-depleted environment and a specialty of organophosphate destructor in eco-niches to which they once emerged, including Zostera spp. roots. The ALP clusterization and an identity level of the genus-specific biosynthetic genes encoding for ectoine and polyketide cluster T1PKS, responsible for sulfated extracellular polysaccharide synthesis, coincide with a new whole genome-based taxonomic classification of the genus Cobetia. The LPS-dephosphorylating property of the PhoA family C. amphilecti ALP CmAP may be used in the development of anti-inflammatory drugs.