晋策 林田

Clostridium saccharoperbutylacetonicum のautolysinのアニオン交換体に対する特異的挙動

The autolysin (N-acetylmuramidase) of Clostridium saccharoperbutylaceto nicum (ATCC 13564) strongly adsorbed to anion exchangers such as diethylaminoethyl (DEAE)-cellulose, triethylaminoethyl (TEAE)-cellulose and ECTEOLA-cellulose. Therefore, the adsorbed autolysin was not eluted with buffer containing various concentrations of NaCl or buffer of various pHs. However it could be eluted from them with the buffer containing high concentration of guanidine·HCl, dioxane and ethylene glycol, which were the reagents used for break of hydrogen bonding of proteins or weakening the hydrophobic interaction of proteins. These results indicated that the hydrophobic interaction would be participate in this strong adsorption of autolysin on the anion exchangers. The autolysin could not adsorb to carriers of the anion exchangers (cellulose, agarose and Sephadex), while it adsorbed to aminoalkyl-Sepharose and alkyl-Sepharose prepared. The adsorption rate of autolysin toward those resins increased in proportion of the elongating length of alkyl chain Therefore, its adsorption to the anion exchangers was thought to be caused by affinity for hydrophorbic residues, namely alkyl residues of di-(or tri-)ethylaminoethyl groups of them. These properties of autolysin were applied on its purification, and the specific activity of DEAE-cellulose eluents by guanidine·HCl increased in 20 times more than that of gel filtrated fraction.