Kinetic and anion inhibition studies of a β-carbonic anhydrase (FbiCA 1) from the C4 plant Flaveria bidentis

Protonography, a technique applicable for the analysis ofη-carbonic anhydrase activity

“…The only z-CA crystallized so far has three slightly different active sites on the same polypeptide chain, whereas X-ray crystal structures of d-and Z-CAs are not available so far [12][13][14][29][30][31][32][33][34][35] . Many classes of CA inhibitors (CAIs) are known to date: the metal complexing anions and the unsubstituted sulfonamides which bind to the Zn(II) ion of the enzyme either by substituting the non-protein zinc ligand or add to the metal coordination sphere, generating trigonal-bipyramidal species are the classical, are the most frequently investigated ones 15,[36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52] . In addition to them, coumarins, phenols, dithiocarbamates and xanthates as well as polyamines, are new classes of CAIs reported in the last years by these groups 9,[53][54][55][56][57][58][59][60][61][62][63] .…”

Expression and characterization of a recombinant psychrophilicγ-carbonic anhydrase (NcoCA) identified in the genome of the Antarctic cyanobacteria belonging to the genusNostoc

“…As indicated in Figure 4, after 60 min of incubation the activity of the Antarctic enzyme decreased to 20% at temperatures higher than 45 C, and was completely inactivated at 60 C. Otherwise, PgiCA, the mesophilic enzyme, retained its activity up to 60 C (Figure 4) at all incubation times. It is interesting to note that the Antarctic enzyme showed an optimal activity at low temperature (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) C) compared to the mesophilic counterpart (PgiCA). This behavior was observed at all the incubation times ( Figure 4) reflecting a typical feature of the cold-adapted enzyme.…”

“…Carbon dioxide (CO 2 ) is an important molecule in all life processes and is generated in high amounts in all organisms, which developed catalysts for its transformation into protons and bicarbonates [1][2][3][4][5][6][7][8][9][10][11] . These catalysts are the enzymes known as carbonic anhydrases (CAs, EC 4.2.1.1) which catalyze the CO 2 hydration/dehydration reversible reaction: CO 2 + H 2 O > HCO À 3 + H +1, [3][4][5][6]8,[12][13][14][15][16][17][18][19] .…”

“…Living organisms encode for at least six distinct genetic families of such catalyst, the a-, b-, g-, d-, z-and Z-CAs 3,10,15,[20][21][22][23][24][25] . The main function of the CAs is to quickly process the CO 2 derived by metabolic processes in order to regulate acid-base homeostasis, connected to the production of protons (H + ) and bicarbonate, also intervening in the secretion of electrolytes and biosynthetic processes in many cell types [1][2][3][4][5][6][7][8][9][10][11] . In fact, pH regulation is a tightly controlled process in most biochemical reactions due to the strong pH dependence of enzyme activity 4, .…”

Biochemical characterization of the chloroplastic β-carbonic anhydrase from Flaveria bidentis (L.) “Kuntze”

“…Recombinant protein was then digested with TEV for 20 h followed by dialysis at 4 C and passed over MonoQ in a linear salt gradient, at pH 8.0 using an AKTA purifier system. Purity and homogeneity of FbiCA1 was assessed by SDS/ PAGE and LC-ESI-MS. Inhibition experiments were performed as previously described 20 .…”