The effects of amino acids on production and transport of α-amylase through bacterial membranes

Abstract

Bacillus subtilis was grown in media containing various amino acids. The effects of these aminoacids on the production of secreted alpha-amylase and membrane-bound alpha-amylase were investigated. Their effects on the transport of alpha-amylase through membranes were also determined. The synthesis rate of alpha-amylase isolated from bacterial membranes was stimulated by growth in media separately containing Ala and Arg, all other amino acids being inhibitory. Cys, Arg and Leu increased the transport of alpha-amylase through the membrane, while Ala, Asp and Ser inhibited it. Secreted alpha-amylase activity was appreciably stimulated by Ala, Arg, Gin, Gly, Leu, Phe, Pro, and especially Cys while it was repressed by Asp, Asn, Glu, Lys, Met, Ser, Thr and Trp.