biostudies-literatureUnknown120(12)Shatursky OYThe geometry of the channel formed by nontoxic derivative of diphtheria toxin CRM197 in lipid bilayer was determined using the dependence of single-channel conductance upon the hydrodynamic radii of different nonelectrolytes. It was found that the cis entrance of CRM197 channel on the side of membrane to which the toxoid was added at pH 4.8 and the trans entrance on the opposite side at pH 6.0 had effective radii of 3.90 and 3.48 Å, respectively. The 3-alkyloxycarbonylmethyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium salts reversibly reduced current via CRM197 channels. The potency of the blockers increased with increasing length of alkyl chain at symmetric pH 6.0 and remained high and stable at pH 4.8 on the cis side. Comparative analysis of CRM197 and amphotericin B pore size with the inBiophysical journal2577-2591https://www.ebi.ac.uk/biostudies/studies/S-EPMC8390859biostudies-literatureThe geometry of diphtheria toxoid CRM197 channel assessed by thiazolium salts and nonelectrolytes.PMC8390859Kolibo DVShatursky OYTrikash IOUsenko MOBorisova TAGorbatiuk OBVovk AIManoilov KYKobzar OLZhukova DAKomisarenko SVfalseThe geometry of diphtheria toxoid CRM197 channel assessed by thiazolium salts and nonelectrolytes.The geometry of the channel formed by nontoxic derivative of diphtheria toxin CRM197 in lipid bilayer was determined using the dependence of single-channel conductance upon the hydrodynamic radii of different nonelectrolytes. It was found that the cis entrance of CRM197 channel on the side of membrane to which the toxoid was added at pH 4.8 and the trans entrance on the opposite side at pH 6.0 had effective radii of 3.90 and 3.48 Å, respectively. The 3-alkyloxycarbonylmethyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium salts reversibly reduced current via CRM197 channels. The potency of the blockers increased with increasing length of alkyl chain at symmetric pH 6.0 and remained high and stable at pH 4.8 on the cis side. Comparative analysis of CRM197 and amphotericin B pore size with the in2021-01-01T00:00:00Z2021 Jun2025-04-19T18:18:30.656Z2025-04-19T18:18:30.656ZS-EPMC83908593394002210.1016/j.bpj.2021.04.028