The Effects of Amino Acids on Production and Transport of α-Amylase through Bacterial Membranes

Bacillus subtilis was grown in media containing various amino acids. The effects of these amino acids on the production of secreted α-amylase and membrane-bound α-amylase were investigated. Their effects on the transport of α-amylase through membranes were also determined. The synthesis rate of α-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 α-amylase through the membrane, while Ala, Asp and Ser inhibited it. Secreted α-amylase activity was appreciably stimulated by Ala, Arc, Gln, Gly, Leu, Phe, Pro, and especially Cys while it was repressed by Asp, Asn, Glu, Lys, Met, Ser, Thr and Trp.