ClC sycA-like chloride channel proteins. This ClC family presents in bacteria, where it facilitates acid resistance in acidic soil. Mutation of this gene (sycA) in Rhizobium tropici CIAT899 causes serious deficiencies in nodule development, nodulation competitiveness, and N2 fixation on Phaseolus vulgaris plants, due to its reduced ability for acid resistance. This family is part of the ClC chloride channel superfamiy. These proteins catalyse the selective flow of Cl- ions across cell membranes and Cl-/H+ exchange transport. These proteins share two characteristics that are apparently inherent to the entire ClC chloride channel superfamily: a unique double-barreled architecture and voltage-dependent gating mechanism. The gating is conferred by the permeating anion itself, acting as the gating charge.
Jiyao W et al.(2023). "The conserved domain database in 2023.",