7.2.1.1 2,5-dibromo-3-methyl-6-isopropyl-4-benzoquinone a known inhibitor of the bc1 and b6f complexes found in mitochondria and chloroplasts, also inhibits quinone reduction by the Na+-NQR in a mixed inhibition mode. It does not just act as a simple competitor or redox mediator at the quinol oxidase site, but also as an antagonist to ubiquinone, inducing a redox bypass of the respiratory chain. The compound both acts as an inhibitor and as an alternative substrate of the Na+-NQR of Vibrio cholerae by a specific interaction with the NqrA subunit of the complex 56515 7.2.1.1 2-heptyl-4-hydroxyquinoline - 49716 7.2.1.1 2-heptyl-4-hydroxyquinoline N-oxide - 2007 7.2.1.1 2-n-heptyl-4-hydroxyquinoline N-oxide inhibited by micromolar concentrations. In contrast to the corresponding enzymes from Vibrio harveyi and Klebsiella pneumoniae, the enzyme from Azotobacter vinelandii is resistant to low 2-n-heptyl-4-hydroxyquinoline N-oxide concentrations 2812 7.2.1.1 2-n-heptyl-4-hydroxyquinoline N-oxide - 2812 7.2.1.1 2-n-heptyl-4-hydroxyquinoline N-oxide submicromolar concentrations inhibit 2812 7.2.1.1 2-n-heptyl-4-hydroxyquinoline-N-oxide - 2602 7.2.1.1 3-[(2E,6E)-8-hydroxy-3,7-dimethylocta-2,6-dien-1-yl]-2-methylquinolin-4(1H)-one 2-azido-5-iodobenzoate - 220838 7.2.1.1 5-azido-3-[(2E,6E)-8-hydroxy-3,7-dimethylocta-2,6-dien-1-yl]-2-methylquinolin-4(1H)-one 4-iodobenzoate - 220837 7.2.1.1 Ag+ - 75 7.2.1.1 Ag+ 0.001 mM, partial and very slow inhibition 75 7.2.1.1 Ag+ in the presence of Ag+, rates of NADH oxidation by membranes from the parent Vibrio cholera strain decrease to 14% (0.001 mM Ag+) of the activity observed in the absence of the inhibitor 75 7.2.1.1 Ag+ the enzyme is specifically inhibited by low concentrations of silver ions 75 7.2.1.1 Ag+ specific inhibition 75 7.2.1.1 Ag2+ - 1041 7.2.1.1 Amytal inhibitor with low affinity 3064 7.2.1.1 annonin VI IC50: 0.05 mM 62318 7.2.1.1 aurachin D-42 the quinolone ring and alkyl side chain of inhibitor aurachin bind to the NqrB subunit in the regions Arg-43-Lys-54 and Trp-23-Gly-89, respectively 220836 7.2.1.1 capsaicin inhibitor with low affinity 1947 7.2.1.1 Cd2+ - 52 7.2.1.1 Cd2+ 98% inhibition at 0.1 M, addition of 0.1 M of Cd2+ to the reaction medium results in almost complete inhibition of dNADH:K3 oxidoreductase activity of membrane vesicles from the wild-type strain 52 7.2.1.1 Cu2+ - 19 7.2.1.1 Cu2+ 89% inhibition at 0.1 M, addition of 0.1 mM of Cu2+ to the reaction medium results in almost complete inhibition of dNADH:K3 oxidoreductase activity of membrane vesicles from the wild-type strain 19 7.2.1.1 diphenylene iodonium - 1616 7.2.1.1 diphenyliodonium modifies the noncovalently bound FAD of the enzyme 26600 7.2.1.1 diphenyliodonium 0.05 mM, rapid inhibition, modifies the noncovalently bound FAD of the enzyme 26600 7.2.1.1 iodoacetamide inactivation 67 7.2.1.1 korormicin - 2177 7.2.1.1 korormicin specifically inhibits Na+-NQR at the level of its interaction with ubiquinone 2177 7.2.1.1 korormicin the antibiotic specifically inhibits Na+-NQR at the level of its interaction with ubiquinone. Korormicin affects the enzyme without competition with quinone and binds the enzyme with high affinity 2177 7.2.1.1 meperidin inhibitor with low affinity 5014 7.2.1.1 additional information not inhibited by 0.04 mM Ag+ 2 7.2.1.1 additional information the enzyme is fully resistant to either Ag+ or N-ethylmaleimide 2 7.2.1.1 additional information Na+-NQR from Azotobacter vinelandii is not sensitive to low 2-n-heptyl-4-hydroxyquinoline-N-oxide concentrations 2 7.2.1.1 additional information korormicin has no effect on the enzyme from Haemophilus influenza 2 7.2.1.1 additional information Na+-NQR from Klebsiella pneumoniae is fully resistant to either Ag+ or N-ethylmaleimide 2 7.2.1.1 additional information replacement of the conserved Cys377 residue with alanine in the NqrF subunit results in resistance of the enzyme to Ag+ and to other heavy metal ions; the enzyme is sensitive against SH reagents. Modification of Cys383 by heavy metal ions or by SH reagents can prevent hydride ion transport from NADH to FAD and hence interrupt the Na+-NQR activities 2 7.2.1.1 N-ethylmaleimide - 49 7.2.1.1 NAD+ competitive inhibitor 7 7.2.1.1 NADH incubation of the aerobic enzyme with NADH in the absence of an electron acceptor, the enzyme is destroyed with a half-inactivation time of about 2 min 8 7.2.1.1 NEM 5 mM, inhibits partially and very slowly 89 7.2.1.1 NEM 5 mM, rapid inhibition 89 7.2.1.1 Pb2+ - 139 7.2.1.1 Piericidin A - 5205 7.2.1.1 Rb+ presence of Rb+ induces conformational changes, indicating a changed accessibility of the sodium binding sites 480 7.2.1.1 rolliniastatin-1 - 32724 7.2.1.1 rotenone - 777 7.2.1.1 Thesit specific inhibition 4110 7.2.1.1 Triton X-100 specific inhibition 61 7.2.1.1 Zn2+ - 14 7.2.1.1 Zn2+ 93% inhibition at 0.1 M, addition of 0.1 mM of Zn2+ to the reaction medium results in almost complete inhibition of dNADH:K3 oxidoreductase activity of membrane vesicles from the wild-type strain 14