Activation studies of the ?-carbonic anhydrases from Malassezia restricta with amines and amino acids" in "Activation studies of the beta-carbonic anhydrases from Malassezia restricta with amines and amino acids"

The ?- and ?-class carbonic anhydrases (CAs, EC 4.2.1.1) from the pathogenic bacterium Vibrio cholerae, VchCA?, and VchCA?, were investigated for their activation with natural and non-natural amino acids and amines. The most effective VchCA? activators were L-tyrosine, histamine, serotonin, and 4-aminoethyl-morpholine, which had KAs in the range of 8.21-12.0 µM. The most effective VchCA? activators were D-tyrosine, dopamine, serotonin, 2-pyridyl-methylamine, 2-aminoethylpyridine, and 2-aminoethylpiperazine, which had KAs in the submicromolar - low micromolar range (0.18-1.37 µM). The two bacterial enzymes had very different activation profiles with these compounds, between each other, and in comparison to the human isoforms hCA I and II. Some amines were selective activators of VchCA?, including 2-pyridylmethylamine (KA of 180 nm for VchCA?, and more than 20 µM for VchCA? and hCA I/II). The activation of CAs from bacteria, such as VchCA?/? has not been considered previously for possible biomedical applications. It would be of interest to study in more detail the extent that CA activators are implicated in the virulence and colonisation of the host by such pathogenic bacteria, which for Vibrio cholerae, is highly dependent on the bicarbonate concentration and pH in the surrounding tissue.