53—THE RÔLE OF SH GROUPS IN WOOL

Abstract

The effect of N/IO Na₂CO_a treatment at 45°C on the cystine, lanthionine and sulphur content and on urea-bisulphite solubility was investigated with normal wool and NEMI-treated wool. Similar experiments were carried out on wool treated with M/10 KCN af 45°C and 65°C M/10 Na₂SO₃ at 45°C, M/10 NaHSO₃ at 45°C, 3% NaHSO₃ at 65°C and O·O5–O·5 M HS ·CH₂·COOH at 50 C.

During the treatment of wool with alkali or reducing compounds lanthionine is formed. The rate of lanthionine formation is decreased if part of the combined cysteine groups is blocked by NEMl (N-ethylmaleinimide).

There is a direct correlation between the SH-content of wool and lanthionine formation.

A new mechanism of lanthionine formation in wool is proposed by a direct S_n2 reaction between RS- and the carbon atom in the -C-SS bond of combined cystine or the C-SX bond in cysteine derivatives.

Lanthionine formation is assumed to be a simultaneous side-reaction of disulphide-exchange reactions.