title: Evidence that eosinophils catalyze the bromide-dependent decarboxylation of amino acids.
abstract: Human eosinophils from subjects with or without myeloperoxidase (MPO) deficiency and guinea pig eosinophils are able to decarboxylate L-alanine in the presence of the cationic detergent cetyltrimethylammonium bromide (CTAB) but not in the presence of the nonionic detergent Triton X-100. Instead, both normal human neutrophils and guinea pig neutrophils decarboxylate L-alanine in the presence of either detergent. When the non-bromide-containing cationic detergent cetyltrimethylammonium hydroxide (CTAOH) is used instead of CTAB, the eosinophils from MPO-deficient subjects are unable to decarboxylate L-alanine. Decarboxylation occurs with the combination CTAOH-Br-, but not with the combinations CTAOH-I-, CTAOH-CI-, or CTAOH-F-. Bromide in the absence of CTAOH does not promote decarboxylation. Triton X-100 and deoxycholate are much less effective in promoting decarboxylation in the presence of bromide. L-Lysine and L-aspartic acid are decarboxylated to a considerably lower rate than L-alanine in the presence of CTAOH and Br-. It is concluded that the eosinophils can catalyze the bromide-dependent decarboxylation of the apolar amino acid L-alanine in the presence of a cationic detergent.
mesh_terms: D000409:Alanine / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D002384:Catalysis; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000494:pharmacology*; D003653:Decarboxylation; D003902:Detergents / Q000494:pharmacology*; D004804:Eosinophils / Q000378:metabolism*; D005122:Exudates and Transudates / Q000166:cytology; D006168:Guinea Pigs; D006801:Humans; D009504:Neutrophils / Q000378:metabolism; D009195:Peroxidase / Q000172:deficiency; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*; D013501:Surface-Active Agents / Q000494:pharmacology*
chemical_list: D000596:Amino Acids; D002593:Cetrimonium Compounds; D003902:Detergents; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents; D009195:Peroxidase; D000409:Alanine; D000077286:Cetrimonium