Disease relevance of cynT

• The product of the cynT gene of the cyn operon in Escherichia coli has been identified as a carbonic anhydrase [1].

High impact information on cynT

• Escherichia coli harboring the recombinant plasmid expresses CA activity (2.3 units/mg of cell extract protein) [2].
• The decrease in CO(2) concentration was accelerated by the addition of carbonic anhydrase, indicating that HCO(3)(-), but not CO(2), binds to the protein [3].
• Since carbon dioxide formed in the bicarbonate-dependent decomposition of cyanate diffuses out of the cell faster than it would be hydrated to bicarbonate, the apparent function of the induced carbonic anhydrase is to catalyze hydration of carbon dioxide and thus prevent depletion of cellular bicarbonate [1].
• The deduced amino acid sequence of delta-EhCA1 revealed that it encodes a protein of 702 amino acids (aa) (ca. 77.3 kDa), with a transmembrane N-terminal region of 373 aa and an in-frame C-terminal open reading frame of 329 aa that defines the CA region [4].
• To date, most of the research focus in this organism has involved the partitioning of DIC between calcification and photosynthesis, primarily using measurements of an external versus internal carbonic anhydrase (CA) activity under defined conditions [4].

Chemical compound and disease context of cynT

• A physiological role for cyanate-induced carbonic anhydrase in Escherichia coli [5].

Biological context of cynT

• A delta cynT mutant strain was extremely sensitive to inhibition of growth by cyanate and did not catalyze decomposition of cyanate (even though an active cyanase was expressed) when grown at a low pCO2 (in air) but had a Cyn+ phenotype at a high pCO2 [6].
• Mutations were introduced in corresponding nucleotides in B.subtilis RNA1 and RNA2 of domain V. The mutants were tested for refolding using unfolded protein binding assays with unfolded carbonic anhydrase [7].

Associations of cynT with chemical compounds

• In contrast to the wild-type strain, the growth of the delta cynT strain was inhibited by cyanate, and the mutant strain was unable to degrade cyanate and therefore could not use cyanate as the sole nitrogen source when grown at a partial CO2 pressures (pCO2) of 0.03% (air) [5].
• Carbonic anhydrase functions to prevent depletion of cellular bicarbonate during cyanate decomposition (the product CO2 can diffuse out of the cell faster than noncatalyzed hydration back to bicarbonate) [8].
• The activity is strongly inhibited by the powerful and selective carbonic anhydrase inhibitor, acetazolamide [9].

Other interactions of cynT

• In the study reported here, the physiological roles of cynT and cynX were investigated by construction of chromosomal mutants in which each of the three genes was rendered inactive [5].
• The gene for cyanase is part of the cyn operon, which includes cynT and cynS, encoding carbonic anhydrase and cyanase, respectively [8].

References