Premium
Analysis of folding intermediates from the main toxin of Naja naja samarensis containing two blocked cysteines
Author(s) -
Gacond J.J.,
Rovelli G.,
Bargetzi J.P.,
Juillerat M.A.
Publication year - 1986
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(86)80528-2
Subject(s) - chemistry , cystine , cysteine , fast protein liquid chromatography , amino acid , peptide , folding (dsp implementation) , ion chromatography , naja , stereochemistry , biochemistry , chromatography , high performance liquid chromatography , venom , enzyme , electrical engineering , engineering
The formation of folding intermediates blocked by iodoacetate from the main toxin of Naja naja samarensis was monitored by FPLC and the populations were identified by amino acid analyses. We have determined conditions allowing for the highest yield in the populations with two blocked cysteines. The free cysteines remaining under these conditions were labeled with iodo[ 14 C]acetate and localized by peptide mapping in one of the products isolated by ion‐exchange chromatography (NT 3 III). We have also investigated the effects on the native‐like characteristics of such molecules of an incubation at equilibrium with a mixture of cysteine and cystine. We find that many different molecular populations are present during the folding process and that disulfide exchanges allow for the reconstitution of native‐like products having open disulfides even under strongly denaturing conditions.